Mark Little's WebLog

Blogging versus tweeting?

2012-01-31T12:56:00.000Z

A few years ago when I was thinking about creating a twitter account I pondered about whether it was worth doing when I was blogging. I didn't think I'd use it much! Since creating the account I've been drawn into twitter more and more, so that today I'm finding the roles reversed: blogging is becoming less frequent whilst tweeting is increasing for me.

I think the reason why is pretty obvious: it is so much easier and quicker to tweet than to write a blog. But there are obvious limits in what you can say with 140 characters, so it's not an either/or situation for me. And yet as a result of using twitter I'm finding myself thinking less and less about blogging. That bit I don't quite understand. Now maybe it has nothing to do with my use of twitter; maybe I'd be blogging less regardless of it because of work, family life etc. Who knows? But I do know I find it interesting how twitter has insinuated itself with my life so quickly and seamlessly.

Transactions on Android

2012-01-01T18:03:00.002Z

Every year I try to make time for pet projects, be they learning new languages such as Erlang (one of my 2007 efforts), writing a discrete event simulation package in C++, or one of my best which was writing the world's first pure Java transaction service over Christmas 1996. Most of the time I don't manage to make much progress throughout the year, leaving the bulk of the effort for over the Christmas break.

This year was no different, with "port Arjuna (aka JBossTS) to Android" on my to-do list for months. I've been playing around with Android for quite a while, even collaborating with some friends on writing a game (iPhone too). I know that although it's Java-based, there are enough differences to make porting certain Java applications tricky. But over the years I have found porting transactions to different languages and environments a pretty good way to learn about the language or environment in question.

So as well as doing my usual catch-up on reading material, breaking the back of the Android port was top of my list. Now in the past I'd have higher expectations of what I could accomplish in this time period, but these days I have a family and some things take priority (well, most of the time). But once everyone had opened their presents, let the turkey settle in the stomach and sat down to watch The Great Escape (hey, it's Christmas!) I found time to kick it off.

I started simple in order to remove as many variables from the problem as possible. So I went back to JavaArjuna, the ancestor of JBossTS and all that predated it. It has none of the enhancements that we've added over the years, but places less requirements on the infrastructure. For instance, it was JavaArjuna that I ported to the HP Jornada back in 2001 because it also worked with earlier versions of Java.

As in 2001 it went well and it wasn't long before I had transactions running on my Android device. It was nice to see one of the basic tests running and displaying the typical transaction UIDs, statuses, rolling back, committing, suspending etc. Then I moved on to JBossTS. It wasn't quite as straightforward and there are a few hacks or workarounds in there while I figure out the best way to fix things, but it's done too! I'm pretty pleased by the results and will spend whatever time I have in the coming weeks to address the open issues. And I've definitely learned a lot more about Android.

So overall I think it's been a good pet project for 2011. It also showed me yet again that the architecture and code behind JBossTS that the team's been working on for years is still a highly portable solution. It doesn't matter whether you want transactions on a mainframe, in the cloud, or on a constrained device, JBossTS can do them all!

PaaS 2.0?

2011-12-31T09:35:00.002Z

A while ago I has some things to say about people trying to add a version number to SOA. At the time it was 2.0 and I like to think I had a little to do with the fact that it died almost as quickly as it was created. I won't go into details, but the interested reader can catch up on it all later.

Now a friend who got caught in the SOA 2.0 crossfire came to me recently and pointed out that some people are now trying to coin the term 'PaaS 2.0' and asked my opinion. At first I didn't know what to think because the original reasons I was against SOA 2.0 didn't seem to apply here because PaaS is so poorly understood. There are no fundamental architectural principles around which it has grown. There are very few examples that everyone agrees upon. There's not even an accepted definition!

But that's when it hit me! How can you assign a version to something that is so I'll defined? It's not like the Web, for instance, where it made sense to have a 2.0. Ok there's some good stuff from the likes of NIST, but there's no agreed reference architecture for PaaS, so how precisely can you say something is PaaS 2.0? The answer is that you can't. Now that doesn't mean you won't be able to do so eventually, but there are quite a few prerequisites that have to be satisfied before that can occur.

So what does this mean? Am I against PaaS 2.0 as I was with its SOA cousin? Yes I am, but for different reasons. As I outlined above, I think it's wrong to try to version something that it so ill defined. Let's figured out what PaaS 1.0 is first!

Future of Middleware

2011-12-23T22:29:00.002Z

I think it's fair to say that despite my years in industry I'm still an academic at heart. I like the ability to spend time working on a problem without the usual product deadlines. Of course there's the potential that you come up with something that has little relevance to the real world, but that can be mitigated by staying close to industry through funding, sponsorship or other relationships. Often in industry we don't have the luxury of spending years coming up with the perfect solution and whilst it's for very good reasons, it can be frustrating at times for those involved.

But we all make the best of what we have to work with and I love my current position, despite the fact I get to spend less time researching than I would like. In fact in some ways I now understand what Santosh has been doing for years in directing and pushing others in the right directions, whilst at the same time wanting to get more involved himself but not quite having enough time to do it all.

Therefore, I take any opportunity I can find to dive back into research, write papers, code etc. And attend, and possibly/hopefully present at conferences and workshops that are often dominated by the research community, though obviously with practical overtones. The Middleware conference is one such event that I love to participate with in one way or another. Over the years I've had papers there and been on the program committee, and not once have I been disappointed by the quality of submissions.

So it was great to be asked to write a paper with Santosh and Stuart on the future of middleware for FOME. Truth be told, Santosh did the bulk of the writing and his co-authors provided the disparate data and input that he's excellent at being able to form into a coherent whole. The result is a great paper that I presented in Portugal earlier this month. It went down well and I got a lot of good feedback, both from the academics present as well as industrial participants.

But the real high for me was just being at the workshop and listening to all of the other presentations. I had a wonderful time meeting with others there and getting as immersed in the research atmosphere as it's possible to do in 48 hours. I could cast my mind back many years to when I was in full-time research and compare and contrast with today. I got a lot out of the many conversations I had with researchers, both old and new to the field. I hope I had a positive impact on them too, because I came away invigorated and my mind full of new possibilities.

Wave sick?

2011-11-20T18:46:00.002Z

What with HPTS, JUDCon, JAX, QCon, JavaOne and various business meetings, I've been doing a lot of traveling recently. Time spent on a plane usually means my mind wanders a bit, covering various topics some of them unrelated. One of the things I got thinking about though, was definitely influenced by a series of talks I've been giving for a while, including at my JBossWorld keynote: the history of distributed systems.

I covered it at Santosh's retirement event too, but from a very personal perspective, i.e., how Arjuna related to it, and relate it did, often in a big way. So this got me to thinking about the various technology waves I've lived through and helped influence in one way or another. And it was quite "chilling" for me to realise how much I'd forgotten about what's happened over the past third of a century or more! (And that made me feel old too!)

I often take for granted that I lived through the start of the PC era: there were no PCs when I first started to code. In fact I'd been developing applications on a range of devices before IBM came out with the first PC or before Microsoft came with the first version of Word. I moved through the era of the BBC, ZX80, Commodores, Ataris, etc. into the first Sun machines, Apples, PCs, laptops, desktops, PDAs, smartphones, pads and much much more. A huge change in the way we interact with computers and importantly the data they maintain. Many different paradigm shifts!

Looking at the middleware shifts that accompanied some of these hardware changes and in fact were often driven by them, I've ridden a number of equally important waves. RPC, distributed objects, bespoke enterprise middleware architectures and implementations, standards based, a number of times there have been explosions of languages including functional and object-oriented, Java, open source, Web Services, REST, mobile, ubiquitous computing, and of course fault tolerance running throughout with transactions and replication. And I'm probably forgetting other things in between these waves.

It's been a bumpy ride at times. The move from CORBA to J2EE wasn't necessarily as good as is could have been. Web Services were often vilified far more than made sense if you were objective. But overall I've enjoyed the ride so far, more or less. And now with Cloud, mobile and beyond it's looking like the next decade will be at least as interesting as the last three. I'm looking forward to playing my part in it!

The future PC

2011-11-03T21:54:00.002Z

I've been thinking a lot about what personal compute devices might look like in the future given the amount of time I've been looking at how things have evolved over the past 30 years. Not so much about what a mainframe or workstation computer might look like (assuming they even exist!) but what replaces your laptop, pad, phone etc. Now of course much of what I will suggest is influenced by how I would do it if I could. However, there's also a smattering of technical advancements in there for good measure.

So my biggest bugbear with my current situation is that I have a laptop (two if I include my personal machine), an iPad and a smartphone (two if I include the one I use for international travel). Each of them holds some subset of my data, with only one (laptop) holding it all. Plus some of that data is held in the cloud so I can share it with people or between devices. This is manageable at the moment, but it's frustrating when I need something on my iPad that's on my laptop or something on my phone that's on the iPad (you get the picture).

What I want is the same information available on all of these devices. In fact, what I want is one device that does it all. I rarely use my phone and pad concurrently, or my pad and laptop. There are exceptions of course, but bear with me. (I may be unique in this and some people might want multiple concurrent devices. But that's still possible in this environment.) What would typically satisfy me would be a way to modify the form factor of my device dynamically over time. Taking a touchscreen smartphone through a pad and then to a laptop with large screen, keyboard and trackpad. At each stage I'd like the best performance, graphically and compute, and the most amount of storage.

Is this possible? Well if you look at how hardware had evolved over the past decades it's not that far off. ARM dominates the smartphone arena and although Intel/AMD will eventually find a way into the market my money is on AMD to get to the laptop and workstation performance before they get to the low power consumption sector in any significant manner. So AMD powered laptops that perform equally with their Intel/AMD cousins aren't far off.

What about main memory? Well you only have to look at how things have evolved recently from 512meg through to 8gig and beyond. It's going to be possible to have 8gig smartphones and tablets soon. And SSDs are getting cheaper and cheaper by the month. Capacity-wise it may take them longer to get to the sizes of spinning disks, but once most laptop manufacturers include SSDs by default, the cost per Gig will plummet as their physical sizes continues to do so too. Putting multiple instances in the same device will be possible to fill the size gap too.

Now you could assume that what I'm outlining is a portable disk drive, but it really isn't. I'm assuming it has storage, of course, but I'm also assuming it has a CPU and probably a GPU. Think plug computer, but much smaller and with much more power: certainly the processing power to rival a laptop and probably the graphical power too. I say 'probably' only because I can see situations where the GPU could be part of the form factor you plug the device in to so that you can do work, e.g., the phone housing or the keyboard/screen.

Ok so there we are: my ideal device is the size of a gum packet (much smaller and you'll lose it) and can be plugged into a range of different deployment chassis. Now all I have to do is wait!

HPTS 2011

2011-10-28T20:00:00.002+01:00

I'm back from HPTS and as usual it was a great snapshot of the major things happening or about to happen in our industry. In past years we've had Java transactions, ubiquitous computing, transactions for the Internet and the impacts of large scale on data consistency. We've also had discussions on the possible impact of future (back then) technologies such as SSD and flash on databases and transactions.

This year was a mix too, with the main theme of cloud. (Though it turned out that cloud wasn't that prevalent). I think the best way to summarise the workshop would be concentrating on high performance and large scale (up as well as out). With talks from the likes of Amazon, Facebook and Microsoft we covered the gamut of incredibly large numbers of users (700 million) through eventual consistency (which we learnt may eventually not be enough!)

Even 25 years after it started it's good to see many of the original people behind transaction processing and databases still turning up. (I've only been going since the 90s.) This includes Stonebraker (aka Mr Alphabet Soup), who gave his usual divisive and entertaining talks on the subject of SQL and how to do it right this time, and of course Pat, who instructed us never to believe a #%^#%-ing word he says as he's now back on the side of ACID and 2PC! (All in good fun, of course.)

Now it's important to realise that you never go to HPTS just for the talks. The people are more than 50% of the equation for this event and it was good to see a lot of mixing and mingling. We had a lot of students here this time, so if past events are anything to go by I am sure we will see the influence of HPTS on their future work. And I suppose that just leaves me to upload the various presentations to the web site!

Where have all the postings gone?

2011-10-13T20:25:00.003+01:00

I know I've been blogging a lot this year, yet when I look at the entry count for this blog it's not as high as I had expected. Then I realised that most of my attention has been directed at JBoss. So if you're wondering where I am from time to time, it's over here.

RIP Dennis Ritchie

2011-10-13T20:07:00.002+01:00

It's safe to say that no programming language has had as big an impact on my career as C. It's also safe to say that no operating system has had as big an impact on my career as Unix. So for these reasons and many others it is sad to hear about the passing of Dennis Ritchie. I met him once, many years ago, when he visited the University and spoke about a range of things, including C and Plan 9. He was a great speaker, someone who helped shape the world we live in, and a nice man. Yet another sad day.

Bluestone and Steve Jobs

2011-10-09T19:18:00.002+01:00

Amongst all of the various articles and tributes to Steve Jobs I came across this from Bob, who is one of the people that has influenced my career significantly (and positively!) over the years. So it's interesting to read the influence Steve had on Bob, Bluestone, HP and hence Arjuna, JBoss and now Red Hat (not forgetting the other companies with which Bob's been involved over the years)! Thanks Bob and thanks, indirectly, Steve.

A sad day for Apple and the world

2011-10-06T01:30:00.004+01:00

I'm an Apple user and have been for many years (since the 1990's). I've had desktops, laptops, ipods, iphones and of course various software. I've been an admirer of Apple and Steve Jobs for just as long, so it's really sad to hear that he has passed away today. The world is a little bit darker now, but I hope his legacy lives on. My thoughts go out to his family.

September 11th

2011-09-11T12:46:00.003+01:00

It's that time of year again but of course this time it's 10 years on. Time to reminisce and remember those who weren't so lucky. I've been thinking about this day for a while and wondering about all of those things that I managed to do in the last decade that I wouldn't have been able to if I'd made a slightly different choice back then. They include many of the things I mentioned previously, such as HP, Arjuna Technologies, JBoss, Red Hat, standards involvement etc.

But they all pale into insignificance when I look at my 9 year old son! And then there's nothing more I can really say except thanks.

The impact of Arjuna

2011-09-04T11:20:00.002+01:00

I've mentioned before that I have the privilege of speaking at Santosh's retirement ceremony. I've also said on several occasions how much Santosh and the Arjuna project have influenced my life over the years. So I decided to speak about the transition of Arjuna from a research project that was originally just the vehicle for several of us to get our PhDs, through to today when it's at the heart of the most downloaded application server in the world.

Fairly obviously I have lived through the transition over the past 25 years. And despite having parted ways with my company in 2005, I've been able to continue to work with them, as well as obviously shepherding the transaction system through JBoss and Red Hat. However, it wasn't until I started to write my presentation that everything we've done over the years came back to me. (I suppose that being so close to things sometimes makes you forget.) I found it really hard to cram 25 years into a 60 minute session, so many things had to be left out or confined to a single bullet. For a start, when Arjuna was still a research effort it managed to help at least a dozen of us get PhDs, was the basis for over 50 papers and technical reports, and influenced distributed systems research and companies from IBM to Sun Microsystems.

But it's when you look beyond the research that the real impact becomes apparent. For a start, in 1994 we used it to implement a distributed student registration system that is still not matched by the one now provided by a certain large business management software purveyor. In 1995 the OTS was being developed and that was already influenced by Arjuna, since Graeme was now at Transarc. It wasn't too long before we began to implement an OTS compliant transaction system using Arjuna and this was my first dealing with standards. We also got involved with IBM, Alcatel and others in defining standards for extended transactions through the CORBA Activity Service (which would later be the basis for the various Web Services transactions efforts.) At about the same time Stuart was driving the workflow submission with Nortel and working on OpenFlow.

Then in 1996 Sun released Oak, later to become Java. We all started to use it in a number of areas, including games, a browser (great way to learn HTML) and a web server. I looked at end-to-end transactions and then decided that an even better way to learn the language would be to implement Arjuna in Java. Over two weeks at Christmas 1996 JavaArjuna was born (later to become JTSArjuna when I ported the OTS.) This was before J2EE, before JTA and before JTS. So not only was this the worlds first 100% pure Java JTS, it was the worlds first 100% pure Java transaction service.

It was round then that we created a company to market the Java and C++ implementations. We were acquired by Bluestone, which was subsequently acquired by HP and Arjuna went into their product suites to compete against BEA and IBM (there was no sign of Oracle middleware in those days!) While our time at HP was limited, we still managed to work on two Web Service transactions standards efforts as well as produce the worlds first such product. We also branched out into high performance messaging and building an ORB.

When HP decided it couldn't make a go of software, we created another startup to concentrate on transactions and messaging. We had several successful years, making sales to the likes of TIBCO and WebMethods, creating two new Web Service standards committees in OASIS and finalising two of them (BTP and WS-TX). We also found a market by replacing the transactions and messaging components in JBoss 3 with our own. And within all this, there was still time to write many papers, give many presentations and more worlds firsts, such as XTS.

As I said earlier, in 2005 we sold transactions to JBoss and I bid farewell to Arjuna the company, though obviously Arjuna the technology stayed pretty close! Over the intervening 6 years and an acquisition by Red Hat, we've seen Arjuna (aka JBossTS) incorporated into every version of AS as well as all of our platforms and many projects, even if they're not written in Java. The teams have branched out into REST as well as Blacktie, to offer XATMI support. There's also work on software transactional memory using JBossTS and now, with the move of Red Hat into the cloud, it's available in OpenShift and beyond.

Even this blog is way too short to cover everything that has happened on this 25 year long journey. I haven't been able to cover other aspects such as OpenFlow and messaging, or the impact of the people who have passed through the Arjuna project and Arjuna companies. I've also only hinted at how all of the research we did at the University or in industry has influenced others over the years. I think in order to really do the Arjuna story justice I need to write a book!

Enterprise middleware and PaaS

2011-08-29T09:33:00.002+01:00

I wanted to say more about why existing enterprise middleware stacks can be (should be) the basis for realistic PaaS implementations. If I get time, I may write a paper and submit it to a journal or conference but until then, this will have to do. I'm talking about this at JavaOne this year too, so a presentation may well come out soon.

Fault tolerance

2011-08-21T16:26:00.003+01:00

There was a time when people in our industry were very careful about using terms such as fault tolerance, transactions and high availability, to name just three. Back before the Internet really kicked off (really when the web came along), if you were emailing someone then they tended to either be in academia and in which case they'd be summarily shot for misusing a term, or they'd be in the DoD and in which case they'd probably be shot too! If you were publishing papers or your thoughts for wider review, you tended to have to wait for a year to see publication and that was if reviewers didn't shoot you down for misusing terms, and in which case you had to start all over again. So it paid to think long and hard before you did the equivalent of hitting submit.

Today we live in a world of instant publishing and less and less peer review. It's also unfortunate that despite the fact more and more papers, article and journals are online, it seems that less and less people are spending the time to research things and read up on state of the art, even if that art was produced decades earlier. I'm not sure if this is because people simply don't have time, simply don't care, don't understand what others have written, or something else entirely.

You might ask what it is that has prompted me to write this entry? Well on this particular occasion it's people using the term 'fault tolerance' in places where it may be accurate when considering the meaning of the words in the English language, but not when looking at the scientific meaning, which is often very different. For instance, let's look at one scientific definition of the term (software) 'fault tolerance'.

"Fault tolerance is intended to preserve the delivery of correct service in the presence of active faults. It is generally implemented by error detection and subsequent system recovery.
Error detection originates an error signal or message within the system. An error that is present but not detected is a latent error. There exist two classes of error detection techniques: (a) concurrent error detection, which takes place during service delivery; and (b) preemptive error detection, which takes place while service delivery is suspended; it checks the system for latent errors and dormant faults.
Recovery transforms a system state that contains one or more errors and (possibly) faults into a state without detected errors and faults that can be activated again. Recovery consists of error handling and fault handling. Error handling eliminates errors from the system state. It may take two forms: (a) rollback, where the state transformation consists of returning the system back to a saved state that existed prior to error detection; that saved state is a checkpoint, (b) rollforward, where the state without detected errors is a new state."

There's a lot in this relatively simple definition. For a start, it's clear that recovery is an inherent part, and that includes error handling as well as fault handling, neither of which are trivial to accomplish, especially when you are dealing with state. Even error detection can seem easy to solve if you don't understand the concepts. Over the past 4+ decades all of this and more has driven the development of protocols behind transaction processing, failure suspectors, strong and weak replication protocols, etc.

So it's both annoying and frustrating to see people talking about fault tolerance as if it's as easy to accomplish as, say, throwing a few extra servers at the problem or restarting a process if it fails. Annoying in that there are sufficient freely available texts out there to cover all of the details. Frustrating in that the users of implementations based on these assumptions are not aware of the problems that will occur when failures happen. As with those situations I've come across over the years where people don't believe they need transactions, the fact that failures are not frequent tends to lull you into a false sense of security!

Now before anyone suggests that this is me being a luddite, I should point out that I'm a scientist and I recognise fully that theories and practices in many areas of science, e.g., physics, are developed based on observations and can change when they prove to not be sufficient to describe the things you see. So for instance, unlike those who in Galileo's time continued to believe the Earth was the centre of the Universe despite a lot of data to the contrary, I accept that theories, rules and laws laid down decades ago may have to be changed today. The problem I have in this case though, is that nothing I have seen or heard in the area of 'fault tolerance' gives me an indication that this is the situation currently!

A thinking engineer

2011-08-09T14:55:00.001+01:00

I've worked with some great engineers in my time (and continue to work with many today), and as an aside, I like to think some people might count me in their list. But back to topic: over the years I've also met some people who would be considered great engineers by others, but I wouldn't rate that high. The reason for this is also one of the factors that I always cite when asked what constitute a great engineer. Of course I rate the usual things, such as ability to code, understand algorithms, and know a spin-lock from a semaphore. Now maybe it's my background (I really think not, but threw that out there just in case I'm wrong) but I also add the ability to say no, or ask why or what if? To me, it doesn't matter whether you're an engineer or an engineering manager, you've got to be confident enough to question things you are asked to do, unless of course you know them to be right from the start.

As a researcher, you're expected to question the work of others who may have been in the field for decades, published dozens of papers and be recognised experts in their fields. You don't take anything at face value. And I believe that that is also a quality really good engineers need to have too. You can be a kick-ass developer, producing the most efficient bubble-sort implementation available, but if it's a solution to the wrong problem it's really no good to me! I call this The Emperor's New Clothes syndrome: if he's naked then say so; don't just go with the flow because your peers do.

Now as I said, I've had the pleasure to work with many great engineers (and engineering managers) over the years, and this quality, let's call it "thinking and challenging" is common to them all. It's also something I try to foster in the teams that work for me directly or indirectly. And although I've implicitly been talking about software engineering, I suspect the same is true in other disciplines.

True Grit update

2011-08-09T14:51:00.002+01:00

A while ago I mentioned that I was reading the novel True Grit and was a fan of the original film, which I watched when I was a child. I also mentioned that I probably wouldn't be watching the remake of the film as I couldn't see how the original could be improved. Well, on the flight back from holiday I had the opportunity to watch it and decided to give it a go.

I've heard a few things about the new film and they can all me summarised as saying that it was a more faithful telling of the story than the John Wayne version. After watching both, and reading the book, I have to wonder if those reviewers knew WTF they were on about! Yes the new film is good, but it's no where near as good as the original. And as for faithfulness to the book? Well with the exception of the ending, the original film is far closer to the book (typically word for word). While watching the remake I kept asking myself time and again why had they changed this or that, or why had they completely rewritten the story in parts?!

If you have a great novel that you know works well on screen, why do script writers seem incapable of leaving it untouched? Maybe they decided that they had to make the new film different enough from the original so people wouldn't think it was a scene-for-scene copy. But in that case, why remake it in the first place? FFS people: if an original film is good enough, leave it alone and learn to produce some original content for once! And for those of you interested in seeing the definitive film adaptation of the book, check out the John Wayne version.

Gone fishing!

2011-07-29T13:25:00.001+01:00

I'm on holiday in Canada, visiting my in-laws. Usually it takes me a few days to wind down from work, but it happens and I relax for the rest of the holiday. (Well, until a few days before I cone back, when I start to think about work again!) Access to email is limited usually, as I'd need to borrow time on my father-in-laws machine. That extra effort is usually enough for me to only check email every few days.

Unfortunately this time I brought my iPad and iPhone, both of which I connected to the wifi. Checking email was too easy and as a result I was working every day! Fortunately it only took me about 4 days to realise this (with some not-so-subtle hints from family) and I disabled wifi. This means I can now get on with the holiday. Since we are out in the middle of nowhere this means sitting by the pool reading a book on my (wifi disabled) iPad, or fishing!

Facebook as Web 3.0?

2011-07-29T13:17:00.003+01:00

I'm not on Facebook and think social networking sites are inherently anti-social (you can't beat a good pub!) However, I know many people who are into them and I've even decided to check out Google+. So they probably have a place in the web firmament.

But recently I've started to see more and more adverts substituting the good old vendor URL for a Facebook version, e.g., moving from www.mycompany.com to www.Facebook.com/mycompany. Now at first this might seem fairly innocuous, but when you dig deeper it's anything but! As I think Tim Berners-Lee has stated elsewhere, and I'm sure Google has too, the data that Facebook is maintaining isn't open for a start, making it harder to search outside of their sub-web. And of course this is like a data cloud in some ways: you're offshoring bits of your data to someone else, so you'd better trust them!

I don't want to pick on any single vendor, so let's stop naming at this point. Even if you can look beyond the lack of openness and the fact that you're basically putting a single vendor in charge of this intra-web, what about all of the nice things that we take for granted from http and REST? Things such as cacheing, intelligent redirects and HATEOAS. Can we be sure that these are implemented and managed correctly on behalf of everyone?

And what's to say that at some point this vendor may decide that Internet protocols are just not good enough or that browsers aren't the right view on to the data? Before you know it we would have a multiverse of Webs, each with their own protocols and UIs. Interactions between them would be difficult if not impossible.

Now of course this is a worst case scenario and I have no idea if any vendors today have plans like this. I'd be surprised if they hadn't been discussed though! So what does this mean for this apparent new attitude to hosting "off the web" and on the "social web"? Well for a start I think that people need to remember that despite how big any one social network may be, there are orders of magnitude more people being "anti-social" and running on the web.

I'm sure that each company that makes the move into social does so on the back of sound marketing research. Unfortunately the people making these decisions aren't necessarily the ones who understand what makes the web work, yet they are precisely the people who need it to work! I really hope that this isn't a slippery slope towards that scenario I outlined. Everyone on the web, both social and anti-social, would lose out in the end! Someone once said that "just because you can do something doesn't mean you should do something."

The end of a space era

2011-07-21T15:00:00.003+01:00

It's sad to see the end of the space shuttle era. I remember being excited to watch the very first launch whilst at school. I remember exactly where I was when Challenger was destroyed: at university stood in a dinner queue. I remember watching when they deployed (and then later fixed) Hubble. Again, I can remember where I was when Columbia was destroyed: at home watching! I've even been to see a launch and heard it come back a week or so later.

So it's fair to say that I grew up with the shuttle over these past 30 years and it's going to be strange not having it around any more. Despite the fact that it may never have been the perfect launch vehicle (I still recall early discussions around HOTOL, for instance), I think it did it's job well. I know I'll miss it.

Santosh's retirement

2011-07-19T15:55:00.002+01:00

I think I've spoken a number of times about how important Professor Shrivastava has been in my academic and professional career over the past 25 years (ouch!) Well he's retiring soon and the University will never quite be the same, at least as far as I'm concerned. But at least I get a chance to speak at his retirement event. Congratulations Santosh and many thanks!

InfoQ and unREST

2011-07-18T22:57:00.002+01:00

I wrote this article for InfoQ because I thought what JJ had said was interesting enough that a wider audience should consider it. I'm still not sure if I'm pleased, surprised or disappointed with the level of comments and discussion that it received. Something for me to contemplate when I'm on vacation I suppose.

When email and vacation don't mix

2011-07-07T15:45:00.002+01:00

I'm off on vacation soon for a couple of weeks. Going to Canada to visit my wife's parents. They live in the back-of-beyond, which is great for getting away from it all. As usual I've promised my wife I won't be taking my work laptop with me, which means that I won't have access to our VPN and hence no access to work email. In the past this used to bother me, because I always want to know what's going on in case there are problems at work. But it's obviously not conducive to a relaxing time.

Now I know some people who go on vacation and can read work email do read work email just to keep the amount of catch up they have to do when they return to a minimum. I expect that after a couple of weeks vacation I'll have several thousand emails to go through, so I can understand what they're doing. However, it won't work for me: I tried it a few times and I just can't help responding to emails if I see them! So what started as a 60 minute attempt during a vacation to cut down on the junk in my inbox ended up several hours later with me only about 10% of the way through. So I don't do that any more and I just take the hit when I get back.

However, I did figure out a compromise (pretty obvious really): I have a backup email address that is accessible off our VPN and which only certain people know about. They know they can get me on this at pretty much any time of the day or night. So if something comes up while I'm away this year, I can find out about it. Of course this has a slight downside in that I know immediately that any emails on that address are probably emergencies! Well, you can't win them all I suppose!

When is a distributed system not a distributed system?

2011-06-26T18:50:00.002+01:00

I've been involved with distributed systems since joining the Arjuna Project back in the mid 1980's. But distributed systems date back way before then, to at least the 1970's with the advent of the first RPC. There are a few definitions of what constitutes a distributed system, including Tanenbaum's "A collection of independent computers that appears to its users as a single coherent system" and this one "A distributed system consists of a collection of autonomous computers, connected through a network and distribution middleware, which enables computers to coordinate their activities and to share the resources of the system, so that users perceive the system as a single, integrated computing facility", though my favourite is still Lamports "You know you have a distributed system when the crash of a computer you’ve never heard of stops you from getting any work done". Back when I started in the area, someone at the University once said that a precise definition was difficult, but you should recognise a distributed system when you saw it.

What all of the definitions have in common is the notion that a distributed system consists of nodes (machines) that are connected by some distributed fabric, e.g., an ethernet. Distributed systems therefore pose problems that are no present in centralised, single machine systems, such as faults (independent failures can now occur) and hence failure detection. Various techniques, such as distributed transactions and replication have grown up to help deal with some of these issues. Other approaches, such as Voltan, also help to build fail-silent processes. And of course we have techniques such as message passing, RPC and shared tuple spaces, were developed to help make developing distributed applications easier. Though of course we learned that complete distribution opacity is not always a good idea. (We did a lot of the early work in this area.)

However, time has moved on and whilst distributed systems continue to be important in our every day lives, the fact is that many of the problems they present and many of the solutions that we have developed, are present within a local environment these days. Think of this like inner space versus outer space, if you like, but the way in which multi-core machines have become the norm means that we have failure independent nodes (cores this time) within a single machine. Alright, they're not connected by an ethernet, but there's a bus involved and they may, or may not, have shared memory too.

Of course none of this is new by any means. If you've ever experienced any of the parallel computing technologies that were the rage back in the 1980's and 1990's, such as the Transputer (excellent architecture and Occam was brilliant!) then you'll understand. There's always been a duality between them distributed systems. But back then parallel computing was even rarer than distributed computing, simply because the costs of the former were prohibitive (which is why a lot of parallel computing research was often done by running COTS hardware on a fast network, because it was cheaper!)

Times have certainly changed and we can no longer consign parallel computing to the realm of high performance computing, or niche areas. It's mainstream and is only going to increase. And I believe that this means distributed systems research and parallel computing efforts must converge. Many of the problems posed by both overlap and solutions for one may be relevant to the other. For instance, we've put a lot of effort into scalability in distributed systems, and failure detection and independence at the hardware (core) level is very advanced.

So when is a distributed system not a distributed system? When it's a centralised multi-core system!

Open Source in action.

2011-06-18T22:17:00.002+01:00

I've been with JBoss since 2005 and in that time I like to think I've experienced quite a bit about how open source works. It's been a wonderful learning experience for me and definitely turned me from someone who thought open source code and developers were somehow not as good as closed source equivalents into a person who knows that the opposite is most definitely the case!

Case in point: over the last 18 months or so we've been on an aggressive schedule for JBossAS 7, which has some pretty fundamental architectural changes in it. This would've been a challenge for any team (I remember how long it took us to implement HP-AS, for instance, and that team was also extremely skilled). But our teams are small and are responsible not only for development, but also for their communities too: open source means a lot more than just having your code in a public repository!

So these teams are putting in a lot of effort! They're pulling long hours too. Now of course that's not unique to open source or JBoss, but the developers are not doing this for their wages; they're doing it because they have a passion for open source and also for the history behind JBoss and our communities. They (we) believe that this is a game changer and not just another battle in the ongoing war. It's worth noting that I saw this in my Bluestone days too, both when we were independent and then part of HP. I think that the reasons behind that are very similar, only the protagonists have changed.

This release is also so fundamental to everything we are doing that even teams who wouldn't normally have much to do with AS are willing to pitch in, both during work hours and personal time. And what's more interesting is that I rarely have to ask them to help: it's a natural thing for them to do because they're as much a part of the AS community as others. From a personal perspective I've found the AS7 effort very enlightening. I've learned a lot, and much of it not just technical in nature. It is most definitely a good time to be in this role!

Addicted?

2011-06-12T15:31:00.003+01:00

My wife is an addictions counsellor with a strong background in psychology. It's amazed me the sorts of things that people can become addicted to and I won't go into them here! However, she's always said that the first step to addressing any addiction is for the addict to admit it. Now according to her I am addicted to work (her definition of work includes anything that involves a computer, including books and papers, so it's quite broad). I have to admit that I do spend an inordinate amount of time doing things that fall into that definition; even when I'm watching TV I'll usually have a book or laptop on my knee (now it's often my iPad). But I'm not sure I'd say I was an addict. And even if I am, I'm not sure I'd want to be "cured". I think a lot of my friends and colleagues would also fall into that category. But then that last statement does apply to many other forms of addiction. Hmmmm.

New age developers?

2011-06-11T22:11:00.004+01:00

I'm getting really tired (aka fed up) hearing about "new age" developers and applications, when certain people talk about the cloud. Look, there are only developers and applications! There's nothing "new age" about this. Some things change, as with each new wave of technology, but many things remain the same. Sure the problem space has changed and we are seeing new applications and approaches being developed, but let's not imbue mythical attributes to those applications or developers! They're no better or worse than developers or apps of the past. Though if you listen to some, "new age" means thinking and working so far outside the box that you're in the next reality! This is starting to get ridiculous and in the local vernacular it's getting on nerves! Evolution people, not revolution!

Updating the history of Arjuna

2011-06-05T22:20:00.002+01:00

Back in 2002 when I was still with HP and our transaction system was still called Arjuna, I wrote a paper with Santosh on the transition of what had started out purely as an academic vehicle for getting a few of us PhDs, into a rather successful product. Back then we conjectured what might happen in the next few years, but the reality has turned out to be even more interesting.

We've always talked about updating the paper, but it's never happened. So it was with interest that we were asked to write a new version as part of a book for Brian Randell's birthday. The paper is almost finished and it has been a lot of fun working on it and remembering all of the things that have happened in the intervening decade: HP leaving the middleware space and us starting again with Arjuna, Web Services transactions, joining JBoss and taking Arjuna there, Red Hat, REST and more. Not all of it will be in this paper, but then maybe that leaves room for yet another update?!

One thing that updating the paper clearly showed was that something that started life as an academic project has not only had an impact on many products over many years, but also an impact on the people who have worked on it. Individuals have come and gone from the team over the years and they've all left their mark on the system and vice versa. And like the system, they've been a great group of people! So whether it's called Arjuna, JBossTS or something else, it and this paper remain a tribute to them all.

Heisenberg and the CAP theorem

2011-06-05T21:56:00.003+01:00

For many years I've been working on extended transactions protocols. The CORBA Activity Service, WS-TX and now REST-TX are efforts on that road. There are many similarities between the problems of long running transactions and large scale replication, so the facts that I did my PhD on both gave me some insights to helping resolve both.

One of the early pieces of research I did was on combining replication and transactions to create consistency domains, where a large number of replicas are split into domains and each domain (replica group) has a relationship with the others in terms of their state and level of consistency. Rather than try to maintain strong consistency between all of the replicas, which incurs overhead proportional to the number of replicas as well as their physical locality, we keep the number of replicas per domain small (and hopefully related) and grow the number of domains if necessary. Then each domain has a degrees of inconsistency with others in the environment.

The basic idea behind the model is that of eventual consistency: in a quiescent period all of the domains would have the same state, but during active periods there is no notion of global/strong consistency. The protocol ensures that state changes flow between domains at a predefined rate (using transactions). A client of the inconsistent replica group can enquire of a domain the state at any time, but may not get the global state, since not all updates will have propagated. Alternatively a client can request the global state but may not know the time it will take to be returned.

If you know Heisenbergs Uncertainty Principle then you'll know that it means you cannot determine the momentum and position of a particle at the same time (or other related properties). Thus it was fairly natural for me to use this analogy when describing the above protocol: an observer cannot know the global state of the system and when that will be the steady state at the same moment, i.e., it's one or the other. It's not a perfect analogy, but in a time when others seemed to like to bring physics into computing it seemed appropriate.

Now of course the original work was before the CAP theorem was formalised. So today we see people referring to that whenever they need to talk about relaxing consistency. And of course that is the right thing to do; if I were reviewing a paper today that was about relaxing consistency and the authors didn't reference CAP then I'd either reject it or have a few stern words to say to them. But I still thing Heisenberg is a way cooler analogy to make. However, I do admit to being slightly biased!

Dublin here I come!

2011-06-05T12:43:00.003+01:00

I'm off to the Red Hat Partner Summit in Dublin in a few hours time. I'm giving a couple of presentations, one on the future of JBoss and one on how JBoss and the Cloud come together. I'm looking forward to them because the audience will be slightly different to those I've presented these topics to over the past few months, so it'll give me a chance to get much broader feedback. Plus it's been a while since I was in Dublin last, so hopefully there'll be a chance to get out and enjoy the place too.

Future of Middleware

2011-06-03T12:15:00.003+01:00

There's a special event being organised as part of Middleware 2011 called the Future of Middleware Event (FOME). I've been asked to contribute to the event and associated paper/book, along with my friend, co-creator of Arjuna and long time mentor Professor Shrivastava. I'm looking forward to it, because it's related to quite a few things that I'm doing elsewhere too!

Architectural discussions and plans

2011-06-02T21:00:00.001+01:00

I haven't had a chance to blog here much recently because my attention has been elsewhere, particularly around JBoss specific activities. One of the ones I'm really enjoying at the moment is thinking about the future of JBoss. Since some of this is really independent of JBoss implementations and more to do with where I think middleware in general could/should go, I may try and keep some of the discussions here and cross link in both directions.

International Workshop on Clouds for Enterprises 2011

2011-05-27T12:31:00.000+01:00

Call for Papers: The International Workshop on Clouds for Enterprises (C4E) 2011

http://nicta.com.au/people/tosicv/clouds4enterprises2011/

held at the 13th IEEE Conference on Commerce and Enterprise Computing (CEC'11, http://www.tudor.lu/cec2011)

on Monday, 5 September 2011 in Luxembourg, Luxembourg

Important dates:

Paper submission: Monday, 20 June 2011 (strict, except for re-submission of papers reviewed by CEC'11)

Notification of acceptance: Monday, 4 July 2011

Description:

Cloud computing is an increasingly popular computing paradigm that aims to streamline the on-demand provisioning of software (SaaS), platform (PaaS), infrastructure (IaaS), and data (DaaS) as services. Deploying applications on a cloud can help to achieve scalability, improve flexibility of computing infrastructure , and reduce total cost of ownership. However, a variety of challenges arise when deploying and operating applications and services in complex and dynamic cloud-based environments, which are frequent in enterprises and governments.

Due to the security and privacy concerns with public cloud offerings (which first attracted widespread attention), it seems likely that many enterprises and governments will choose hybrid cloud, community cloud, and (particularly in the near future) private cloud solutions. Multi-tier infrastructures like these not only promise vast opportunities for future business models and new types of integrated business services, but also pose severe technical and organizational problems.

The goal of this workshop is to bring together academic, industrial, and government researchers (from different disciplines), developers, and IT managers interested in cloud computing technologies and/or their consumer-side/provider-side use in enterprises and governments. Through paper presentations and discussions, this workshop will contribute to the inter-disciplinary and multi-perspective exchange of knowledge and ideas, dissemination of results about completed and on-going research projects, as well as identification and analysis of open cloud research and adoption/exploitation issues.

This workshop invites contributions from both technical (e.g., architecture-related) and business perspectives (with governance issues spanning both perspectives). The topics of interest include, but are not limited to:

Technical Perspective:

- Patterns and best practices in development for cloud-based applications

- Deployment and configuration of cloud services

- Migration of legacy applications to clouds

- Hybrid and multi-tier cloud architectures

- Architectural support for enhancing cloud computing interoperability and portability

- Architectural principles and approaches to cloud computing

- Cloud architectures for adaptivity or robustness

- Evaluation methods for cloud architectures

- Architectural support for dynamic resource management to support computing needs of cloud services

- Cloud architectures of emerging applications, such as mashup of enterprise/government services

- Impact of cloud computing on architecture of software and, more generally, IT systems

Enterprise/Government Application Perspective:

- Case studies and experience reports in development of cloud-based systems in enterprises and governments

- Analyses of cloud initiatives of different governments

- Business aspects of cloud service markets

- Technical and business support for various cloud service market roles, such as brokers, integrators, and certification authorities

- New applications and business models for enterprises/governments leveraging cloud computing

- Economic evaluation of cloud-based enterprises

Governance Perspective:

- Service lifecycle models

- Architectural support for security and privacy

- Architectural support for trust in/by cloud services

- Capacity planning of services running in a cloud

- Architectural support for quality of service (QoS) and service level agreement (SLA) management

- Accountability of cloud services, including mechanisms, algorithms and methods for monitoring, analyzing and reporting service status and usage profiles

- IT Governance and compliance, particularly in hybrid and multi-tier clouds

Review and publication process:

Authors are invited to submit previously unpublished, high-quality papers before

***20 June 2011***.

Due to the limited time for review, this is a strict paper submission deadline and extensions will be given only to re-submission of papers reviewed by CEC'11 (authors of these papers will have about 3 days after CEC'11 notification to improve their papers). Papers published or submitted elsewhere will be automatically rejected. All submissions should be made using the EasyChair Web site http://www.easychair.org/conferences/?conf=c4e2011.

Two types of submissions are solicited:

* Full papers – describing mature research or industrial case studies – up to 8 pages long

* Short papers – describing work in progress or position statements – up to 4 pages long

Papers presenting and analyzing completed projects are particularly welcome. Papers about on-going research projects are also welcome, especially if they contain critical, qualitative and quantitative analysis of already achieved results and remaining open research issues. In addition, papers about experiences and comparative analysis of using cloud computing in enterprises and governments are also welcome. Submissions from industry and government are particularly encouraged. In addition to presentation of peer-reviewed papers this one-day workshop will contain a keynote from an industry expert and an open discussion session on practical issues of migrating legacy enterprise and government applications to clouds.

All accepted papers (both full and short) will be published by the IEEE and included into the IEEE Xplore digital library. A follow-up journal issue with improved and extended versions of the best workshop papers is also planned.

Paper submissions must be in the IEEE conference paper format. Papers in other formats will be rejected automatically. Guidelines and templates for this format are available at: http://www.ieee.org/conferences_events/conferences/publishing/templates.html. All submissions should include the author's name, affiliation and contact details. The document format for all paper submissions is Adobe PDF.

All submissions will be formally peer-reviewed by at least 2 Program Committee members. The authors will be notified of acceptance by

***4 July 2011***.

Since this date is very close to the deadline that the workshop chairs have for submission of camera-ready papers to the IEEE, there will be very short time (if any) for improving accepted submissions into camera-ready versions of the final papers. Further information about the procedure will be provided to the authors closer to the notification date.

At least one author of every accepted paper must register for the whole CEC’11 conference (there is no separate workshop registration) and present the paper.

Inquiries about paper submission should be e-mailed to Dr. Vladimir Tosic (vladat at server: computer.org) and include "Clouds for Enterprises 2011 Inquiry" in the Subject line.

Workshop Chairs:

Dr. Vladimir Tosic, NICTA, Australia; E-mail: vladat (at: computer.org) – primary workshop contact

Dr. Andrew Farrell, HP Labs, UK; E-mail: andrew.farrell (at: hp.com)

Dr. Karl Michael Göschka, Vienna University of Technology, Austria; E-mail: Karl.Goeschka (at: tuwien.ac.at)

Sebastian Hudert, University of Bayreuth, Germany; E-mail: sebastian.hudert (at uni-bayreuth.de)

Prof. Hanan Lutfiyya, University of Western Ontario, Canada, E-mail: hanan (at: csd.uwo.ca)

Dr. Michael Parkin, Tilburg University, The Netherlands, E-mail: m.s.parkin (at: uvt.nl)

Workshop Program Committee (to be completed):

Danilo Ardagna, Politecnico di Milano, Italy

Tina Balke, Uni. Bayreuth, Germany

Paul L. Bannerman, NICTA, Australia

Rajkumar Buyya, Uni. Melbourne, Australia

Shiping Chen. CSIRO, Australia

Torsten Eymann, Uni. Bayreuth, Germany

Felix Freitag, Uni. Politècnica de Catalunya, Spain

Lorenz Froihofer, A1 Telekom Austria, Austria

Ian Gorton, PNNL, USA

Matti Hiltunen, AT&T Labs, USA

Christophe Huygens, Katholieke Uni. Leuven, Belgium

Hans-Arno Jacobsen, Uni. Toronto, Canada

Bastian Koller, HLRS, Germany

Kevin Lee, Murdoch Uni., Australia

Mark Little, Red Hat, UK

Yan Liu, PNNL, USA

André Ludwig, Uni. Leipzig, Germany

John Mace, Newcastle Uni., UK

Patrick Martin, Queens Uni., Canada

Leandro Navarro, Uni. Politècnica de Catalunya, Spain

Rui Oliveira, Uni. Minho, Portugal

José Orlando Pereira, Uni. Minho, Portugal

Nicolas Repp, TU Darmstadt, Germany

Giovanni Russello, CREATE-NET, Italy

Derong Shen, Northeastern University, China

Philipp Stephanow, Fraunhofer SIT, Germany

Francois Taiani, Lancaster Uni., UK

Yazhe Tang, Xi'an Jiaotong Uni., China

Eddy Truyen, Katholieke Uni. Leuven, Belgium

Hiroshi Wada, NICTA, Australia

Philipp Wieder, TU Dortmund, Germany

Guido Wirtz, Uni. Bamberg, Germany

Yun Yang, Swinburne Uni. of Tech., Australia

Liangzhao Zeng, IBM Research, USA

Ubiquitous Computing

2011-05-16T19:01:00.001+01:00

Another cross post about JBossEverywhere.

Compute and Data Clouds

2011-05-16T18:32:00.002+01:00

I've discussed several times about the need for public and private clouds. Unfortunately it's still possible to find people and vendors who believe that only public clouds are "true" clouds, whatever that means. From a purely technical perspective I am disappointed because the scientist in me always tries to take an objective stance. Factor in the business side and I can understand why they make these statements. It doesn't make it right in my book though.

However, I want to move the debate on because I think some stances are unlikely to change any time soon. So I began to think of the real reasons behind cloud: what brought us to where we are today, both social as well as technical. In some ways this is related to the posting I'll make later on the vision behind JBossEverywhere, but even that goes back even further to the root of cloud: grid computing and ubiquitous computing.

I was involved in some of the grid efforts in the early 2000's, particularly around the area of transactions and, independently, Web Services. In fact it was several of my friends and colleagues, several of whom were working for me at Arjuna, who wrote a seminal paper on the subject that really did stir up a hornets nest at the time.

However, I digress. If you look back at the grid work at the time, it had really coalesced into two different, though related, use cases: compute grids, where the networked resources worked in parallel on a (typically) small set of data that was farmed out to them by some central server(s), and the data grid, where the resources cooperate on processing a (typically) large data set that may have taken hours or days to download to them and which they may all share. The software and architecture of both types of grids could be markedly different for very good reasons, including fault tolerance and security.

Well I think those same reasons need to be applied to the cloud. Why would someone go to the expense of setting up a private cloud, for instance, versus a public clouds? Why would you use a hybrid approach? Ultimately I believe it is because of the data, and have said so before: the cloud will go to the data and not the other way around. But why? For the same reasons as the grid. If you have lots of data that would take hours or days to upload to a cloud, then you probably don't want to go the public route as failures (e.g., the AWS outage) could cost you valuable time and money, not forgetting the headache of ensuring that that much data can remain secure! But if you can split the data into logical quanta that can be processed relatively independently, then you could gain from the public cloud, even if just as an "overflow" mechanism when your private cloud runs out of capacity, as securing smaller amounts of data can be easier to accomplish and a failure should be more self contained.

Hmmm, I wonder if there's also a suitable analogy to make here with traditional ACID transactions and long running (extended) transactions?

Anyway, I believe that the public, private or hybrid debates should move on and we need to be talking about compute and data clouds. At that level the choice of *where* to host the work becomes more obvious and should be taken out of the hands of subjective vendor debates.

Papers, papers everywhere ...

2011-05-16T12:17:00.003+01:00

Recently I got harangued by a couple of people for not having a list of my papers and books on the blog. (Go figure!) So here goes, and probably eventually I'll link to downloadable versions (until then just remember that Google Is Your Friend!)

Note, this does not include standards and specifications I've worked on! Furthermore, it's definitely out of date by a few years as well as me forgetting a few things that have happened over the past 20. Check here for a more accurate list, though I suspect even that has some problems.

Journals

M.C. Little and D.L. McCue, “Construction and Use of a  Simulation Package in C++," C User's Journal Vol. 12, Number 3, March 1994.
G.D. Parrington, S.K. Shrivastava, S.M. Wheater and M.C. Little, "The Design and Implementation of Arjuna," USENIX Computing Systems Journal, Vol 8, No 3, 1995.
D.B. Ingham, M.C. Little, S.J. Caughey, and S.K. Shrivastava, "W3Objects: Bringing Object-Oriented Technology to the Web," World Wide Web Journal, Issue 1, pp. 89-105.
D.B. Ingham, S.J. Caughey, and M.C. Little, "Fixing the Broken-Link Problem: The W3Objects Approach," Computing Networks & ISDN Systems, Vol. 28, No. 7-11, pp. 1255-1268.
D.B. Ingham, M.C. Little, S.J. Caughey, and S.K. Shrivastava, "W3Objects: Distributed Objects and the Web," Dr. Dobb's Sourcebook, Vol. 22, No. 13, pp. 19-25, January/February 1997.
M.C. Little and S.K. Shrivastava, "Providing end-to-end transactional Web applications using the Object Transaction Service", OMG Success Story, August 1998.
M.C. Little and S.K. Shrivastava, "Java Transactions for the Internet" (Extended version), Special Issue of the Distributed Systems Engineering Journal, Volume 5, Number 4, December 1998.
L.B. Arief, M.C. Little, S.K. Shrivastava, N.A. Speirs and S.M. Wheater, "Specifying Distributed System Services", BT Technology Journal, Vol. 17 No. 2 April 1999, pp. 126-136.
Mark C. Little and Santosh K. Shrivastava, "Integrating Group Communication with Transactions for Implementing Persistent Replicated Objects", Lecture Notes in Computer Science, vol. 1752, Springer-Verlag, pp. 238-253.
Mark C. Little, Stuart M. Wheater, David B. Ingham, C. Richard Snow, Harry Whitfield, and Santosh K. Shrivastava, "The University Student Registration System: A Case Study in Building A High-Availability Distributed Application Using General Purpose Components", Lecture Notes in Computer Science, vol. 1752, Springer-Verlag, pp. 453-471.
Mark Little, “Transactions and Web Services”, HP Middleware Developer Journal, February 2002.
M. C. Little, N. A. Speirs and S. K. Shrivastava, “Using Bloom Filters to Speed-up Name Lookup in Distributed Systems”, The Computer Journal, Vol. 45, Issue 6, pp. 645-652 Oxford University Press/British Computer Society, 2002.
S. Dalal, S. Temel, M. Little, M. Potts and J. Webber, “Coordinating Business Transactions on the Web”, IEEE Internet Computing, January 2003.
M. Little, “Transactions and Web Services”, Communications of the ACM Special Issue, Volume 46, Issue 10, October 2003, pp. 49-54.
I Houston, M. C. Little et al, “The CORBA Activity Service Framework for Supporting Extended Transactions”, Software: Practice and Experience, Vol. 33, Issue 4, pp. 351-373, 2003.

Articles

“The Business Transactions Protocol”, Developer.Com, March 2002, http://softwaredev.earthweb.com/sdtech/article/0,,12065_1121331_4,00.html
“SOAP for the masses”, WebServices.org, July 24th 2005.
“Web Services Transactions and Heuristics”, WebServices.org, 10th March 2005.
“The OASIS WS-CAF Approach to Web Services Business Transactions”, WebServices.org, 25th January 2005.
“The Smorgasbord of Web Services Transactions”, WebServices.org, 17th January 2005.
“End-to-end transactionality: myth or reality?”, Java Developer Journal, March 2002, pp. 56-62.
“An overview of support for extended transaction models in J2EE”, Developer.com, May 2002.
“The Business Transactions Protocol”, Developer.com, May 2002.
J. Webber, V. Corrales, M. Little and S. Parastatidis, “Making web services work”, Application Development Advisor, November/December 2001 issue.
B. Martin and M. Little, “ACID is Good. Take it in Short Doses”, The ServerSide article, October 2004, http://www.theserverside.com/articles/article.tss?l=AcidShortDoses.
S. Parastatidis, M. Little and J. Webber, “Stateful Interactions in Web Services”, Web Services Journal, May 2004.
M. Little and J. Webber, “Introducing WS-CAF”, Web Services Journal, November 2003.
M. Little and T. Freund, “A comparison of Web services transaction protocols”, IBM DeveloperWorks article, October 2003. http://www-106.ibm.com/developerworks/webservices/library/ws-comproto/
M. Little and J. Webber, “Introducing BPEL4WS 1.0”, Web Services Journal, July 2003.
M. Little and J. Webber, “Introducing WS-Transaction part 2”, Web Services Journal, June 2003.
J. Webber and M. Little, “Introducing WS-Transaction part 1”, Web Services Journal, May 2003.
J. Webber and M. Little, “Introducing WS-Coordination”, Web Services Journal, April 2003.

Conferences/Workshops

M.C. Little and S.K. Shrivastava, "Replicated K-Resilient Objects in Arjuna," Proceedings of IEEE Workshop on the Management of Replicated Data, pp. 53-58, Houston, Texas, November 1990.
D.L. McCue and M.C. Little, "Computing Replica Placement in a Distributed System," Proceedings of the IEEE Workshop on Replicated Data, pp. 58-61, Monterey C.A., November 1992.
M.C. Little, D.L. McCue and S.K. Shrivastava, "Maintaining Information about Persistent Replicated Objects in a Distributed System," Proceedings of Thirteenth International Conference on Distributed Computing Systems, pp. 491-498, Pittsburgh, May 1993.
M.C. Little and D.L. McCue, "The Replica Management System: a Scheme for Flexible and Dynamic Replication," Proceedings of the Second International Workshop on Configurable Distributed Systems, Pittsburgh, March 1994.
M.C. Little and S.K. Shrivastava, "Using Application Specific Knowledge for Configuring Object Replicas," Proceedings of the Third International Conference on Configurable Distributed Systems, pp. 169-176, Annapolis, Maryland, May 6-8, 1996.
S.M. Wheater and M.C. Little, "The Design and Implementation of a Framework for Configurable Software," Proceedings of the Third International Conference on Configurable Distributed Systems, pp. 136-143, Annapolis, Maryland, May 6-8, 1996.
M.C. Little, S.K. Shrivastava, S.J. Caughey, and D.B. Ingham, "Constructing Reliable Web Applications using Atomic Actions," Proceedings of the Sixth International World Wide Web Conference, Santa Clara, USA 7-11 April 1997.
S.J. Caughey, D.B. Ingham, and M.C. Little, "Flexible Open Caching for the Web," Proceedings of the Sixth International World Wide Web Conference, Santa Clara, USA 7-11 April 1997.
D.B. Ingham, S.J. Caughey, and M.C. Little, "Supporting Highly Manageable Web Services," Proceedings of the Sixth International World Wide Web Conference, Santa Clara, USA 7-11 April 1997.
M.C. Little and S.K. Shrivastava, "Distributed Transaction in Java," Contribution to High Performance Transaction Systems (HPTS) workshop, Monterey, Sept. 1997.
S.J. Caughey, M.C. Little and S.K. Shrivastava, "Checked Transactions in an Asynchronous Message Passing Environment", The 1st IEEE International Symposium on Object-oriented Real-time distributed Computing, Kyoto, Japan. April 1998.
M.C. Little and S.M. Wheater, "Building Configurable Applications in Java," The 4th International Conference on Configurable Distributed Systems (ICCDS'98), Annapolis, Maryland, USA, May 4-6, 1998.
M.C. Little and S.K. Shrivastava, "Java Transactions for the Internet," The 4th Conference on Object-Oriented Technologies and Systems (COOTS'98), Santa Fe, New Mexico, USA, April 1998.
M.C. Little and S.K. Shrivastava, "Understanding the Role of Atomic Transactions and Group Communications in Implementing Persistent Replicated Objects," The 8th International Workshop on Persistent Object Systems: Design Implementation and Use, Tiburon, California, USA, 30th August - 1st September 1998.
M.C. Little and S.K. Shrivastava, "Integrating the Object Transaction Service with the Web", Proceedings of the 2nd IEEE Workshop on Enterprise Distributed Object Computing (EDOC'98), November 3-5 1998, La Jolla, California.
G. Morgan, S.K. Shrivastava, P.D. Ezhilchelvan and M.C. Little, "Design and Implementation of a CORBA Fault-tolerant Object Group Service", Proceedings of the Second IFIP WG 6.1 International Working Conference on Distributed Applications and Interoperable Systems, DAIS'99, Helsinki, June 1999.
M.C. Little and S.K. Shrivastava, "Implementing high availability CORBA applications with Java", Proceedings of the IEEE Workshop on Internet Applications, San Jose, California, June 1999.
M.C. Little, "Object decomposition in transactional applications", Contribution to the Eighth International Workshop on High Performance Transaction Systems, Pacific Grove, California, September 26-29, 1999.
M.C. Little and S.K. Shrivastava, "A method for combining replication with cacheing", IEEE International Workshop on Reliable Middleware Systems (WREMI'99), Proceedings of the 18th IEEE Symposium on Reliable Distributed Systems, Lausanne, Switzerland, October 19-22, 1999.
P.D. Ezhilchelvan, S.K. Shrivastava and M.C. Little, “A Model Architecture for Conducting Hierarchically Structured Auctions”, Proceedings of the 4th IEEE Symposium on Object-Oriented Real-time Computing (ISORC), May 2001, Magdeburg, Germany.
M. Little, S. Shrivastava and S. Wheater, “Theory and Practice of building Reliable Distributed Applications”, Proceedings of the 3rd International Symposium on Distributed Objects and Applications, September 2001, Rome, Italy.
M.C. Little et al, “The CORBA Activity Service Framework for Supporting Extended Transactions”, Proceedings the IPIC/ACM International Conference on Distributed Systems Platforms (Middleware 2001), November 2001, Heidelberg, Germany.
M. C. Little and S. K. Shrivastava, “An Examination of the Transition of the Arjuna Distributed Transaction Processing Software from Research to Products”, In Proceedings of the 2nd USENIX Workshop on Industrial Experiences with Systems Software (WIESS '02), Boston, MA, USA, 8 December 2002 (Co-located with OSDI '02) USENIX Association.
A. I. Kistijantoro, G. Morgan, S. K. Shrivastava and M.C. Little, “Component Replication in Distributed Systems: a Case study using Enterprise Java Beans”, 22nd IEEE/IFIP Symposium on Reliable Distributed Systems (SRDS2003), Florence, October 2003.
M. Little, “Full Circle for Web Services Transactions?”, Proceedings of the High Performance Transaction Systems Workshop, Asilomar, October 2003.
M. Little and E. Newcomer, “Interposition, Web Services and the Bable Fish”, Proceedings of the High Performance Transaction Systems Workshop, Asilomar, October 2003.
M. Little, “Web services transactions: past, present and future”, Proceedings of the XML 2003 conference, Philadelphia, December 2003.
M. Little, “Models for Web services transactions”, Proceedings of SIGMOD 2004, Paris, France, June 2004.
M. Little, “An Open Standards Approach to Web Services Business Transactions”, Proceedings of XML Open 2004, Cambridge University, September 2004.
D. Bunting and M. Little, “Business Process Context: Context, coordination and transactions in the Web Services architecture”, Proceedings of XML 2004, Washington DC, November 2004.
M. Little and D. Bunting, “WS-CAF and the Web Services architecture”, Proceedings of XTECH 2005, Amsterdam, The Netherlands, May 2005.
M. Little and S. Shrivastava, “The evolution of a transaction processing system”, Proceedings of the High Performance Transaction Systems Workshop, Asilomar, September 2005.
M. Little, “Blackadder and the micro-kernel approach to Web Services transactions”, Proceedings of the High Performance Transaction Systems Workshop, Asilomar, September 2005.
M. Little, E. Newcomer and G. Pavlik, “WS-CAF: Contexts, Coordination and Transactions for Web Services”, Proceedings of the High Performance Transaction Systems Workshop, Asilomar, September 2005.
M. Little, G. Pavlik and A. Kumar, “The Session Concept for Web Services”, Proceedings of XML 2005, Atlanta, GA, November 2005.
M. Little, G. Pavlik and A. Kumar, “The need for sessions in Web Services”, Proceedings of 3rd European Conference on Web Services, Sweden, November 2005.
M. Little, “The need for a general context definition in Web Services”, Proceedings of the W3C Workshop on the Web of Services, February 2007.
M. Little, “Transactions and open source: two steps forward, one step backwards?”, Proceedings of the High Performance Transaction Systems Workshop, Asilomar, October 2007.
M. Little, “High Performance Name Lookups”, Proceedings of the High Performance Transaction Systems Workshop, Asilomar, October 2009.
M. Little, “REST-based transactions”, Proceedings of the High Performance Transaction Systems Workshop, Asilomar, October 2009.
Achmad I. Kistijantoro, Graham Morgan, Santosh K. Shrivastava, and Mark C. Little, “Enhancing an Application Server to Support Available Components”, IEEE Transactions on Software Engineering, Vol. 34, No. 4, pp. 531-545, July/August 2008.

Others

“Replication of Transactional Objects”, International Symposium on Distributed Objects and Applications (DOA’01), Rome, Italy, September 2001.
“The development of Web Transactions”, OMG Web Services Workshop, San Jose, March 2002.
“Transactions and Web Services: present and future”, OMG Workshop, Zurich, March 2002.
“Beyond the Stock Quote: BTP, the long and short IT (Internet Transactions)”, JavaOne, San Francisco, March 2002.
“Extended transactions”, ServerSide.com Tech Talk, February 2003.
“Demystifying Java Transaction Processing”, JavaOne, San Francisco, July 2004.
“The Future of Grid Technologies”, JavaOne, San Francisco, June 2005.

Project Deliverables

G. Ferrari, P. Ezhilchelvan and M. Little, “Realistic and Tractable Modelling of Multi-tiered E-business Service Provisioning”, TAPAS Project deliverable, April 2005.
S.M. Wheater and M.C. Little, "The Design and Implementation of a Framework for Extensible Software," BROADCAST Project Technical Report.
M.C. Little and S.K. Shrivastava, "Object Replication in Arjuna," BROADCAST Project Techical Report, 50, October 1994.
G.D. Parrington, S.K. Shrivastava, S.M. Wheater and M.C. Little, "The Design and Implementation of Arjuna," BROADCAST Project Techical Report, 65, October 1994.
M.C. Little and S.K. Shrivastava, "Object Replication in Arjuna," Draft Version Newcastle University, Computing Science Laboratory, August 1993.
M.C. Little, D.L. McCue and S.K. Shrivastava, "Maintaining Information about Persistent Replicated Object in a Distributed System," BROADCAST Project Techical Report, October 1993.
S.K. Shrivastava, P.D. Ezhilchelvan and M.C. Little, "Understanding Component Failures and Replications in Distributed Systems," ISA Technical Report, UNT/TR1, May 1990.
S.K. Shrivastava, G.N. Dixon, M.C. Little, G.D. Parrington, F. Hedayati and S.M. Wheater, "The Design and Implementation of Arjuna," Technical Report Series, 280, University of Newcastle upon Tyne, Computing Laboratory, March 1989.

Books

M. Little, J. Maron and G. Pavlik, “Java Transaction Processing: Design and Implementation”, Prentice Hall. July 2004.
J. McGovern, A. Williamson, M. Little, A. Jain et al, “The J2EE 1.4 Bible”, Wiley Associates, December 2003.
J. McGovern, M Little et al. “Enterprise Service Oriented Architecture”, Prentice Hall. Publication date to be announced.
Chapter on Web Services Transactions, MIT Press Publication on “The Web Services Architecture”, 2005.

A worrying lack of physics!

2011-05-15T10:55:00.004+01:00

Half of my undergraduate degree was spent in advanced physics, including astronomy, astrophysics and high-energe particle physics. I loved all of those subjects and they continue to influence me today. Despite moving from academia to various companies, I've stayed pretty close to the University, so it's with great sadness that I've witnessed the collapse of subjects such as physics within it over the past few years.

Therefore, it's even more worrying to read articles such as this. People who don't really understand the importance of science are making judgements about its future without seeking the right level of consultancy, or listening to what they are being told. But then what's new? Maybe they'll understand history more?

JBoss Everywhere

2011-05-09T15:47:00.003+01:00

It's a catchy title but manages to capture in two words a lot of what I've been thinking about as the future of middleware for well over a decade (or two!) I'll dig into detail in future entries, but for now it's worth just cross linking the article I wrote earlier.

We live in interesting times ...

2011-04-27T19:21:00.002+01:00

To paraphrase Robert Kennedy, "we definitely live in interesting times", or at least you do if you're part of JBoss. What with the language work we're doing around Ceylon, some great work with JRuby over in TorqueBox-land, major improvements in transactions performance, world domination from the Infinispan team (well, most of our teams to be perfectly honest!), strong involvement in the EE7 standardisation process, yet more world domination and great work from the Drools team, and so many other things going, it has been impossible for me to write about them all. We've even seen several of our competitors start to copy our PaaS story in recent weeks (well, they do say that imitation is the sincerest form of flattery!)

I've been meaning to write about several of these items for a while. But what with JBossWorld/JUDCon, working on the long term vision for JBoss, various off site meetings, and a vacation to Orlando (which turned into a successful working holiday), I simply haven't had time. But once we get over conference season I hope to get a bit of breathing room and revisit one or two of them. At the very least I'll be writing more on what I'll be talking about during my keynote, though if you were at my presentation during QCon London then you might be able to make an intuitive leap before then!

In conclusion it's worth saying that in the 6 years that I've been a part of JBoss I can't recall a time when there was as much innovation and excitement within the projects and their communities. This is definitely a great time for us!

JBossWorld 2011

2011-04-27T17:57:00.002+01:00

Not long now until JBossWorld and JUDCon. I'm presenting at both this year, but probably the most important aspect will be my keynote. Since taking over from Sacha 2 years ago, I've given a state of the union at each JBossWorld, but this time will be different: yes we'll cover what has happened over the past 12 months, but the real meat of the presentation will be unveiling where we are going in the next few years. So if you haven't registered yet for either event, do so now (I think JUDCon attendees get free access the my keynote!)

True Grit

2011-03-20T18:33:00.002Z

I remember vividly the first time I saw True Grit: I was 7 years old and on a family holiday and my father and I snuck off to watch it. I loved it then and I continue to love it whenever I watch it. So it was with some apprehension that I heard they were making another movie. I still haven't seen it but I probably will eventually.

However, it was while I was reading about the new movie that I realised I'd not actually read the book. I did some research about it and kept hearing how good it was. When I saw some reviewers likening it to one of my favourite books of all time (To Kill A Mockinbird), I knew I had to give it a go. Well I'm almost finished the book and I have to admit it is definitely up there as a classic. If the new movie is as good, then I think it'll be worth a viewing. Though it'll have to go some to displace the original movie in my heart!

HPTS 2011 Call For Papers

2011-03-14T20:39:00.000Z

Call for Participation

14th International Workshop

on High Performance Transaction Systems (HPTS)

October 23-26, 2011

Asilomar Conference Grounds

Pacific Grove, CA

The ubiquity of the Internet and the proliferation of "smart" devices have led us to a world where large, scalable, data-intensive systems -- once the rarified domain of mainframe computers and financial institutions -- now permeate virtually every industry. Social networks, online ticketing systems, and massively multiplayer online games are just a few of the applications regularly used by hundreds of millions of users that depend daily on such systems. System architects and engineers face increasingly complex challenges: larger scale, lower power, more client heterogeneity, etc. In addition, the skies are rapidly "cloud"ing up -- and some of the world's largest systems are being built from parts or platforms that are "non-traditional" in nature. The "NoSQL movement" is upon us, data analytics are running on thousand-node clusters, and almost every one of our traditional assumptions is being questioned by a new generation of data system architects.

Every two years, HPTS brings together a lively and opinionated group of participants to discuss and debate the pressing topics that affect today's systems and their design and implementation. Past workshops have included topics such as emerging directions in systems infrastructure, new applications, and current developments in software and technology. The topics are limited only by the imagination of our participants. The workshop will include position paper presentations, panels, moderated discussions, and significant time for casual interaction. And of course beer.

We ask potential participants to submit a short (two paragraph) technical summary, a one-page position paper, or an abstract of their current work. Submissions can present a viewpoint on a controversial topic, a summary of lessons learned, experience with a large or unusual system, an innovative mechanism, an enormous problem looming on the horizon, or anything else that convinces the program committee that the participant has something interesting to say. The submission process is purposely lightweight, but we require each submission to have only a single author.
The workshop is by invitation only and is limited to approximately 75 participants. The submissions drive both the invitation process and the workshop agenda. Participants may be asked to be part of a presentation or discussion session at the workshop.

Send submissions, in plain text, to hpts2011@ics.uci.edu no later than 11:59 PM (EST) April 1, 2011.

A note to Program Committees

2011-03-05T18:36:00.004Z

Over the years I've written over 50 papers, many technical reports, quite a few magazine articles and several books, not to mention a PhD thesis. I've sat on enough program committees over the past 20+ years to know that it is a difficult job, particularly if you've got a lot of papers to review and very little time. That's why assembling the program committee is often one of the most challenging tasks for the conference/workshop chairs.

Throughout this time I think I've had a pretty good paper acceptance ratio, but I have had papers rejected by conferences and workshops. I think if you weren't disappointed about a rejection then you probably didn't put in enough effort to the paper writing in the first place, and that's definitely something I do for every paper. So it's true to say that when our WS-REST paper was rejected we were all disappointed.

I'm not going to go into whether or not I agree with the reviewers: that would be inappropriate. But at least one of them did frustrate me with something I've seen done once or twice elsewhere and each time I see it I get really annoyed. As a reviewer, whether for a conference/workshop, a journal or elsewhere, you often want to illustrate your points, both positive and negative, by drawing the attention of the authors to other papers or works. But if you're going to do this make sure that those papers or citations are publicly available or it really is pretty pointless: you may as well be saying "You are wrong; I know it but I refuse to tell you why and you just have to believe me because I am a reviewer!", which is obviously not what you expect from peer review! It also doesn't reflect well on the conference.

Over the past few decades some journals and conference/workshop publications have gone private, only being available to paying readers. This does make it hard, but not impossible, to achieve publicly available copies. I remember us doing this back in the 1980's, by publishing technical reports that covered roughly the same content and were primarily there for others to access when the original papers were unavailable. As a member of a program committee you could then refer to these. But one way or another, if you are on a program committee and you're going to want authors to learn from the experience of others and improve their papers based on your comments, either refer to papers that they can access, or don't bother!

ZX81 is 30 years old?!

2011-03-04T12:48:00.003Z

Now this brings back memories! I was never a ZX owner, nor did I own a Spectrum. But they did come out when I was at school and I did write programs for them, so I have fond memories (including using a milk bottle as a heat sink!) My personal computer ownership started with a Commodore Pet (still have it at home!) and then a BBC Model B, both of which were a step up from the punch-tape mainframes that we used in school prior to their arrival! Ah, those were the days!

I confess ...

2011-03-01T14:20:00.002Z

I have to confess that I'm a Bob Hope and Bing Crosby fan. I grew up with their movies, with the Road To ... series as my favourites. But Pale Face is a classic Hope-only movie and that's where I came across Jane Russell. So it's very sad to hear that she has died.

Starlite

2011-02-28T14:01:00.002Z

I remember a few years ago watching a demo of Starlite on Tomorrow's World. I always wondered what happened to Starlite and was reading today that it continues to be stalled and yet apparently passes a host of tests to prove that there really is something behind it! What a shame. It has immense potential.

The future of Java middleware

2011-02-27T18:21:00.002Z

I'm speaking at QCon London again this year and it's on a topic I've been working on for a number of years: where is (Java) middleware going? I'm not going to spoil things too much here, but suffice it to say that anyone who has heard me talk about middleware over the years, probably won't be surprised. I'll blog more about it after the event.

My presentation may be on Java, but what I've got to say transcends any particular language implementation. If Java hadn't come along and we were all still happily working on C++, then I'd be saying similar things. The middleware component of the larger software industry is at an inflexion point and no, Cloud didn't cause it: we've been heading towards this event at full speed for several years. We can either keep heading blindly down the route of inventing bespoke wheels that are often just as round as their cousins elsewhere, or we can start to think and work more efficiently.

I obviously can't speak on behalf of other vendors, but I can say that JBoss will be heading in the right direction! Of course this does not mean we are ditching Java Enterprise Edition, or any of the other investments we've made! But we have been expanding over the years from just JBossAS to other things like Hibernate, ESB, portal, etc. I see what we need to do over the next few years as just another evolution of what we've been doing. And if you look around at the plethora of projects we've got on JBoss.org then you'll be able to see that we've been heading in the direction I'm hinting at for some time.

The next few years are going to be exciting for JBoss. I'm also hoping that we can energise the open source communities as a whole around some of these ideas so that a wider audience can participate and benefit. Like I said ... exciting!

Another era draws to a close

2011-02-23T13:51:00.001Z

For those of us who grew up huddled behind the sofa or simply asking the question "How do Daleks get up stairs?", this is a sad day.

DEC founder dies

2011-02-08T12:00:00.003Z

It's likely that many of the current generation of developers will never have heard of DEC, but they had a profound impact on the way our industry developers. So it's sad to hear that Ken Olsen has died. The PDP-11 will always have a place in my heart!

What do developers want in the Cloud?

2011-02-02T13:09:00.006Z

OK, so the title is a loaded question, because I'm getting hit from all sides with conflicting information. Plus as a developer myself, it's often hard for me to be objective. For instance, not everyone loves emacs the way I do! This could also be a very wide ranging discussion on aspects from repositories through to runtime management. Maybe I'll revisit some of those in later entries, but for now I feel compelled to focus on the editor/IDE component of the development experience.

Over the years I've used a range of different editors and IDEs. I'm not going to list them all here, but the fact that I still use emacs and the command line shows that perhaps I'm not easily pleased. However, whether it's emacs, Eclipse or (shudder) vi, I always have my development code on my laptop or desktop. Yes it may get pulled down from a remote repository, but it's edited locally before being committed back. This is a fairly standard way of doing things and probably the only thing to change over the past 20+ years is the repository aspect. Before cvs, svn and git there were ad hoc solutions, but the result was essentially the same: remote backup/sharing mechanism but local development.

Does cloud change this? Well I hadn't really put too much thought into this because I really didn't (don't) think it does. As a developer I still need a repository (OK, that could be hosted in the Cloud - I don't care as long as it is available when I check out and check in code). And I still need a local development environment with an IDE or editor, right? Well there's the problem. I think I do and I know quite a lot of people who think similarly. These folks are long time developers across a range of industries and academia, who expect to be able to code locally and deploy remotely into the (public or private) Cloud.

However, it seems that there is an alternative option, where everything is remote, including the code on which you develop. In this scenario the code is maintained in the Cloud (it may still be checked out of some repository, but maybe not). You edit it through a browser (Web 2.0 meets the Cloud) and the environment within the browser is (hopefully) as feature rich as your non-Cloud IDE. And typically this is all based around a 4GL offering.

Now don't get me wrong: I can see how this can all work. From a technical perspective it's pretty straightforward. Plus I don't have a problem with 4GL as far as they go. My problem with this approach is centred around the remote development aspect. As a developer I want to be able to code when I want and where I want, without having to worry about network connectivity issues. I need that off-line aspect. It's actually one of the reasons I'm still not entirely happy with using maven, but I'm getting over that now and am in rehab!

So is this really the kind of development environment/working pattern that Cloud developers want and need? Isn't Eclipse, or even emacs, sufficient and perhaps even preferable? As I said before, it's hard for me to separate what I'd want and expect as a developer from what others might want and expect.

Marc on Hudson/Jenkins

2011-01-29T21:14:00.002Z

I haven't been tracking the Hudson/Jenkins issue in depth, but from what I do know I have to agree with Marc. Community is critical to the success of an open source project, and if your licence allows a fork of the code then it's also possible to fork the community too. Even if forking the code isn't possible, if you don't embrace, support and nurture your communities then they'll either go elsewhere or start a competitive effort themselves. This may sound strange, but this is one of the things that I love about working in open source: it's not just about having the best technology; you need to have the best communities too.

HPTS 2011

2011-01-29T20:56:00.002Z

Anyone who knows me probably knows how much I love the High Performance Transaction Systems workshops that Jim created and mentored for years. I've been going to it for many years and have been on the program committee for the past few. Well I'm pleased to say that we've just announced the Call for Papers for the event this year. If the past workshops are anything to go by then it'll be a great workshop and I'm really looking forward to October!

Beanstalk and PaaS?

2011-01-23T18:50:00.002Z

I didn't get a chance to write up everything I've got to say about the Amazon Beanstalk announcement, particularly as it applies to JBoss. I agree with some of what Sacha and the CloudBees team have to say: it's a good step for Java, but I also think it's pretty obvious that this would happen. I'm not sure if this is an "I told you so" moment.

However, once again I have to say that I agree with Paul on his assessment: it's not quite a PaaS ... yet. It seems that others agree, though not everyone is so sure. I'm sure we will see (have to see) further improvements to what is being offered, but as things stand, this doesn't fit my definition of PaaS. But this is a fast moving arena at the moment, so I wouldn't be surprised to see things change in the future, particularly as the competition starts to heat up.

Steve on public vs private Cloud

2011-01-23T17:28:00.001Z

Steve Jones makes some very similar points to my earlier posting on data and its role in the public versus private cloud debate. Definitely worth checking out.

Edsac being rebuilt

2011-01-13T15:01:00.002Z

Wonderful news. Guess I'll be making a trip once it's completed then!

Software Craftsman

2011-01-12T13:14:00.002Z

I didn't even know there was a Software Craftsman Manifesto, but Dan North makes some good points.

IO, objects and messages

2011-01-09T20:22:00.003Z

I mentioned that one of my Christmas projects involved playing around with the IO programming language. I took it a little further than I'd planned originally and started to look at integrating transactions with it (in the form of the C++ version of Arjuna). I got to know the language pretty well, despite the poor documentation which often caused more delays and hair pulling.

One of the things I realised about half way through was that I really like IO because it has a lot in common with Smalltalk: everything is an object and methods are invoked via the exchange of messages. In some ways it made me realise how much I miss programming with Smalltalk, though that's not to suggest that I preferred one language over the other; it's been a few years since I really used Smalltalk so I'd have to refresh that knowledge to make a qualified judgement.

IO also reminded me that while I love C++ and probably still like it above others, as an object-oriented language it has a number of quirks that don't make it, or similar languages, ideal for beginners learning the ins and outs of OO. One of the things I miss, which was part of the original Smalltalk implementation and Simula, though removed from Smalltalk-80, is the concept of message passing to interact with objects. I always found this concept more natural when thinking about object orientation.

It's probably one of the reasons I took to distributed systems: in the early days of Arjuna, when C++ was chosen as the implementation language over Concurrent Euclid and others, we (mainly Graham) spent a lot of time on making C++ (opaquely) distributed (trailblazing this at the time). Obviously what we ended up with was a system where C++ objects interacted via messages! Since the work Graham did also supported multiple inheritance as well as overloading, it went much further than simply distributing an object's implementation.

Looking back at that period now, I could imagine doing something with that work to move a non-distributed C++ language varient in the direction of message passing, but that would probably have been pointless. C++ is good for what it was aimed at. But I think it, and similar languages such as Java, may not necessarily be the right basis from which to learn initially about object orientation (I still long for multiple inheritance and operator overloading in Java!) I believe that programmers should always have a broad knowledge of languages under their belts and I'm glad I came at C++ through the likes of Simula, Smalltalk, Lisp, Fortran and Forth, to name just a few. Some of them have little to say about object orientation, but I'm sure that all of them have influenced the way in which I think about and approach problems, no matter what the implementation language.

So back to IO. It may have a small following compared to the mainstream languages and it may suffer from poorer documentation than most, but if you've used Smalltalk or thought about learning it, then I'd recommend looking at IO as well. It's not perfect (which language is?) but I'm sure you'll learn something, or perhaps it'll refresh your memories about other languages as it did for me. The result may well be that you chane the way in which you think about object orientation or at least the way you use your favourite language today.

Well done Cambridge

2010-12-28T22:30:00.003Z

Very well done! A bonus Christmas present. Fix the security issue(s) rather than ignore them and attempt to silence those who might call attention to them. OK, the latter might be cheaper and easier in the short term, but as a user I'd much prefer the former was the avenue explored!

And the thesis can be obtained from here.

I must be a traditionalist?

2010-12-24T16:30:00.002Z

Two of my favourite movies at any time of year, but particularly at Christmas, are Scrooge with Alastair Sim (the definitive version IMO, with only Scrooged coming close) and It's a Wonderful Life. Both in black and white as they were intended originally. So what happens this year? The TV is showing colourised versions of them! No, no, no, no, no! That is wrong on so many levels! Almost as bad as "dogs and cats living together".

Now it's entirely likely that if colour film had existed when both movies were made then the directors would have chosen it and those movies would likely look and feel different to their colourised cousins. But the fact is that it wasn't and the film director's, writers etc. used the black and white medium to great effect. It's part of the atmosphere of the movies and is so ingrained in the making of them that when you watch you don't notice it's not in colour. And when you see it in colour today it's just wrong. Almost like watching a program or film based on something that was intended originally for radio. The act of moving it from one medium to another alters it, but rarely do the people involved in that alteration seem to understand that or take it into account.

Colourising films is a great example of the adage that "just because you can do something doesn't mean you should"! So if you have a choice between seeing the above two movies in colour or black and white, I recommend sticking with the original. You won't be disappointed.

A late Christmas present?

2010-12-23T08:42:00.002Z

It's probably too late to expect this for Christmas, but I think a reprint of Geoffrey Hoyle's book is definitely on the cards for the new year!

End of an era

2010-12-22T18:05:00.002Z

It's a bit of a sad day today. For over 10 years I've been using an HP Jornada 720 for a lot more than it was originally intended. But since I got it in 2000 it has become harder and harder to interface it with any of my desktop or laptop machines. You tend not to find machines today with IR or RS232 ports! And getting up-to-date versions of Java for it, for example, have proven difficult, to say the least!

Ultimately over the last couple of years I've been using it as a glorified address book. But as I use my smartphone more, or the built-in equivalent applications on my laptop, resorting to the Jornada became more and more of a hassle. So despite the fact that it is the machine I've used the longest over the past 30 years, I've decided to retire it and it is now resting comfortably in the loft. Maybe, just maybe, I'll resurrect it if the need arises. Until then I'll have fond memories of one of the best and most versatile machines HP ever built!

JUDCon 2011 in Boston

2010-12-20T20:49:00.002Z

I've been thinking about tracks for JUDCon next year and posted a preliminary Call for Presentations earlier today. Take a look if you're at all interested in JBoss as a developer or as a user.

IO

2010-12-20T20:38:00.002Z

Recently I've been reading up on IO the language, not to be confused with IO the moon of Jupiter. It's a very interesting prototype language, based on very few concepts (everything's either an object or a message, objects have slots which are either attributes or methods). It reminds me a lot of Smalltalk. But what surprises me the most is that it is such an extremely simple language and yet it's possible to do some extremely complex things with it. Although this wasn't one of my original pet projects for Christmas, I think it will be now!

I'm not sure if I'll take it further than that, but it's sufficiently different to other languages I've been playing with recently that it may well get some quality time from me as I figure out exactly what it's good for and where its limitations reside. If you're looking for something different in the language arena then take a look too. It won't take long to get to grips with the basics and you might well be pleasantly surprised by what you find.

Data on the outside (of the public Cloud) versus data on the inside (of the public Cloud)

2010-12-19T14:32:00.003Z

A few years back Pat Helland wrote a nice paper about the issues of data outside and inside the services boundary and how the locale impacts traditional transaction semantics. This was around the time that there was a lot of work and publicity around extended transaction models. Pat used an analogy to relativity to drive home his point, whereas I'd been using quantum mechanics analogies. But regardless of how it is explained, the idea is that data and where it is located, is ultimately the bottleneck to scalability if total consistency is required (in a finite period of time).

So what's this got to do with Cloud? Well I've been thinking a lot about Cloud for quite a while (depending on your definition of Cloud, it could stretch back decades!) There are many problem areas that need to be worked out for the Cloud to truly succeed, including security, fault tolerance, reliability and performance. Some of these are related directly to why I believe private Clouds will be the norm for most applications.

But probably the prime reason why I think public Clouds won't continue to hog the limelight for enterprise or mission critical applications is the data issue. Processor speeds continue to increase (well, maybe not individual processor speeds, but when stuck on the same chip the result is the same), memory speeds increase, even disk speeds are increasing when you factor in the growing use of solid state. Network speeds have always lagged behind and that continues to be the case. If you don't have much data/information, or most of it is volatile and generated as part of the computation, then moving to a public cloud may make sense (assuming the problems I mentioned before are resolved). But for those users and applications that have copious amounts of data, moving it into the public cloud is going in the wrong direction: moving the computation to the data makes far more sense.

Now don't get me wrong. I'm not suggesting that public clouds aren't useful and won't remain useful. It's how they are used that will change for certain types of application. Data has always been critical to businesses and individuals, whether you're the largest online advertiser trying to amass as much information as possible, or whether you're just looking to maintain your own financial data. Trusting who to share that information with is always going to be an issue because it is related directly to control: do you control your own information when you need it or do you rely on someone else to help (or get in the way)? I suspect that for the vast majority of people/companies, the answer will be that they want to retain control over their data. (Over the years that may change, in the same way that banks became more trusted versus keeping your money under the mattress; though perhaps the bank analogy and trust isn't such a good one these days!)

Therefore, I think where the data will reside will define the future of cloud and that really means private cloud. Public clouds will be useful for cloud bursting and number crunching for certain types of application, and of course there will be users who can commit entirely to the public cloud (assuming all of the above issues are resolved) because they don't have critical data stores in which they rely or because they don't have existing infrastructure that can be turned into a protected (private) cloud. So what I'm suggesting is that data on the outside of the public cloud, i.e., within the private cloud, will dominate over data on the inside of the public cloud. Of course only time will tell, but if I were a betting man ...

It's Christmas!

2010-12-18T20:22:00.002Z

In the immortal words of the great Noddy Holder and Slade ... It's Christmas (or will be very soon!) I have a couple of weeks off due to not taking much vacation throughout 2010 (which is a pattern I seem to follow every year). So as is usual for any vacation (at least mine), I've written a list, checked it twice, ruled out those things that are naughty, leaving only those that are nice and come up with way more things that I can do in the time available. But hey, it's better to be over active than under!

So what's in the list? Well there's the usual smattering of work related efforts. But I've tried to make the majority of them "pet projects". Of course they'll probably have some impact on work eventually, but that's not the reason for them at this point. Top of my list is doing some refreshers on some languages I haven't had a chance to use much recently, including Ruby and Erlang. Then I've got a paper I want to write on REST and transactions with Bill and Mike (OK, so this is work related, but I do like writing papers, so it almost doesn't count). I want to do some work on JavaSim too and if there's time, get back to my STM effort.

Lots to do. Lots to look forward to. Oh and then there's Christmas too! I love this time of year.

Another CloudBees acquisition

2010-12-15T10:05:00.002Z

This is *not* a CloudBees blog, but yet again I have to say congratulations to Sacha and the team for their latest announcement! Very impressive move.

Nearly two years as CTO

2010-12-12T22:36:00.001Z

A cross post. A quick summary: thanks Sacha!

Cloud 2.0? Give me a break!

2010-12-08T13:40:00.002Z

Over 4 years ago a group of analysts and vendors got together to try and rally around the term SOA 2.0. In an attempt to stop that in its tracks, I said a few things that maybe played a smaller part in helping to show the problems behind the term. I haven't seen or heard of SOA 2.0 much since, so maybe the community effort helped to bring a little sense to the world.

Unfortunately it seems that adding 2.0 to something is still a favourite pastime for those that either can't figure out a good name, or simply don't understand why it works for Web 2.0. With today's announcement that Salesforce have bought Heroku, it seems that we've entered the world of 'Cloud 2'! Oh come on! Let's inject some reality into this again, before it gets jumped on by other vendors or analysts that believe an increment to a term really makes a difference when the technology or architecture hasn't actually evolved.

Apparently Cloud 2 is oriented around social, mobile and real-time. So is this hard real-time, soft real-time, or some other form of real-time, given that when you're using applications in the Cloud today the response is happening in your frame of reference and within your lifetime!

I do believe that the current perception of Cloud is limited to servers and that does need to change, but that can be sorted out by having a true architectural definition of Cloud that is agreed by everyone. But there's no need to call it Cloud 2. In fact that just adds more confusion!

And social aspects of Cloud? Well I'm not a big fan of social networks; I think they're anti-social: go down the pub to see your friends, don't chat to them on IRC!

So let's get a grip on reality! Sticking 2 on the end in the hopes that it'll help will only do the opposite. And as I said for SOA 2.0, if this "social, real-time and mobile" Cloud really is different than what we're getting used to today, then coin a proper term for it, e.g., The Social Cloud.

More sad news!

2010-11-30T16:36:00.003Z

I met Maurice Wilkes a few times when he came to the University to talk. So it's sad to hear that he has passed away. Definitely a pioneer and definitely a very nice man. A sad day indeed.

Busy Bees

2010-11-30T11:03:00.000Z

Once again, congratulations to Sacha and team!

Android woes coming to an end!

2010-11-29T08:15:00.002Z

My time as an Android user is drawing to a close. I may come back when they sort things out so that I am no longer at the mercy of the vague policies from then handset manufacturers or operators for upgrades, when in reality they really want me to buy a new phone and contact every 6 months in order to get even security upgrades.

It was fun whilst it lasted and even with the benefit of hindsight I think it was the right choice at the time. However, it has left a bad taste and Google needs to sort out the mess. Until then I'll probably move to an iPhone. And I can't really think of a better way of putting it than Douglas Adams: So Long, And Thanks for All the Fish!

Management and PaaS

2010-11-21T20:21:00.003Z

Many years ago I spent a few years working for HP as a Distinguished Engineer via their acquisition of Bluestone. Now I learnt a lot through that experience and one of those things was the importance of system management software such as OpenView. In truth I already knew, having done research with HP, IBM and others over the years prior to this; but spending quality time with the team was still informative and illuminating.

Managing middleware systems is a complex task, particularly if you want to do it efficiently and without adversely impacting the system that is being monitored/managed. (Almost like Schrodinger's Cat experiment!) But for large scale, dynamic systems such as those I mentioned previously, good monitoring and management is critical. This remains true if you remove the dynamic/autonomous aspects and assume that a human system administrator will be using the information provided.

This shouldn't come as a surprise. Even your favourite operating system has enjoyed monitoring and management capabilities of various quality over the decades. The good implementations tend to remain in the background doing their job and you don't even know they are there. And of course as soon as you add in the distributed factor, the need for good monitoring and management cannot be over stated.

But of course you can do without; it's just that you may then have to put up with sub-par performance or efficiency as you need to manually cope with failures, changes in network or machine characteristics, etc. Worse still, issues may go unnoticed until far too late, e.g., the lack of orphan detection can lead to multiple competing services corrupting data or conflicting with one another.

So why am I mentioning this? Is it because it's not obvious, or that I'm running out of interesting things to discuss? Not quite! It should be clear that management/monitoring software is important for middleware solutions (and others). Depending upon what you consider to be monitoring and management, it may be a core component of middleware, or a component in middleware (e.g., the previous example on orphan detection and elimination.) But if you're looking at a separate monitoring/management component or infrastructure, then you wouldn't consider that to be your development platform for arbitrary applications, right? You wouldn't, for instance, consider such a software system to be a replacement for your middleware platform, e.g., for CORBA or Java EE.

Over the years I've never heard anyone suggest such a thing, so this isn't something I've even considered people would think. However, recently this has come up in several conversations I've had. And yes, it's in the area of Cloud and specifically PaaS. The statements have been made that PaaS is the monitoring/management, or is all about the monitoring/management. Why would that be any more sensible a statement or position to take in the Cloud world if it wasn't sensible prior to Cloud? I really don't know. It doesn't make sense any more than ...

"Why would a Wookiee, an eight-foot tall Wookiee, want to live on Endor, with a bunch of two-foot tall Ewoks? That does not make sense! But more important, you have to ask yourself: What does this have to do with this case? Nothing. Ladies and gentlemen, it has nothing to do with this case! It does not make sense! Look at me. I'm a lawyer defending a major record company, and I'm talkin' about Chewbacca! Does that make sense? Ladies and gentlemen, I am not making any sense! None of this makes sense! And so you have to remember, when you're in that jury room deliberatin' and conjugatin' the Emancipation Proclamation, does it make sense? No! Ladies and gentlemen of this supposed jury, it does not make sense! If Chewbacca lives on Endor, you must acquit! The defense rests."

With PaaS we're talking about a Platform (the first letter in the acronym kind of gives it away). Now unless you're only developing applications, services or components for your favourite monitoring/management infrastructure, you'll probably consider your platform to be something else entirely, e.g., Java Enterprise Edition with all of its capabilities such as transactions, EJB3, POJOs, messaging, persistence etc. This (as an example) would be your definition of your platform. Very few people would consider OpenView (or whatever they're calling it these days) as their platform. So although something like OpenView, or even JON, are important to any platform, I certainly wouldn't consider them to be the platform.

Or maybe I'm missing something?!

REST + transactions paper

2010-11-19T21:53:00.003Z

We've been working on REST+transactions for a long time now, with a number of iterations and implementations spanning over a decade. After various discussions over the past few months I'm hoping that a few new organizations (academic and industrial) will be coming forward in the near future to help contribute to this work. However, I think it's time we wrote a paper on this and got it published. We've got enough material and experience to target a range of conferences and workshops. Plus I haven't written a paper in a while: I'm starting to feel rusty!

Iconic distributed systems research comes back around

2010-11-19T16:58:00.005Z

Distributed systems research has been going on since the very first time someone decided to network multiple computers. Industry and academia have shared this burden and we're here today because of many different people and organisations. Some of this work is often referenced and built on, such as Lamport's paper on Time, Clocks and the Ordering of Events in a Distributed System, or RFC 707, concerning RPCs. But some of it, such as Stuart's work on Coloured Actions, or much work on weak consistency replication.

However, sometimes it's simply a matter of timing, with some research happening before it's really needed or truly appreciated. Case in point is a lot of the work that we saw produced during the mid 1990's on configurable distributed system and particularly that presented and documented by the IEEE Conference on Configurable Distributed Systems (there were other workshops and institutions doing similar work, but this conference was one that I had personal knowledge about since I had several papers published there over the years). Much of this work concerned autonomous systems that reacted to change, e.g., the failure of machines or networks, or increased work load on a given machine that prevented it from meeting performance metrics. Some of these systems could then dynamically adapt to the changes and reconfigure themselves, e.g., by spinning up new instances of services elsewhere to move the load, or route messages to alternative machines or via alternate routes to the original destination thus bypassing network partitions.

This is a gross simplification of the many and varied techniques that were discussed and developed almost two decades ago to provide systems that required very little manual intervention, i.e., they were almost entirely autonomous (in theory, if not always in practice). With the growing popularity of all things Cloud related, these techniques and ideas are extremely important. If Cloud (whether public or private) is to be differentiated from, say, virtualizing infrastructure in IT departments, then autonomous monitoring, management and reconfiguration is critical to ensure that developers can have on-demand access to the compute resources they need and that the system can ensure those resources are performing according to requirements. This needs to happen dynamically and be driven by the system itself in most cases because there should be little/no involvement by your friendly neighbourhood system administrator (in fact in some cases such an individual may not exist!)

I'm hoping that just because Cloud didn't exist as an identifiable concept back in the 1990's, people and organizations today don't overlook the fact that relevant R&D happened back then. Reworking and retasking some of this prior work could help save us a lot of time and effort, even if it's just to convince engineers today that certain paths or possible solutions aren't viable. For a start I know that I'll be getting my copies of those proceedings out again to refresh my memory!

Nice move by Sacha and Cloudbees

2010-11-09T13:38:00.001Z

From Devoxx ...

"CloudBees, the new company from former JBoss CTO Sacha Labourey, today consolidated its position as the de facto source for Hudson-based continuous integration solutions, from on-premise to the cloud with the acquisition of InfraDNA, the company founded by Hudson creator Kohsuke Kawaguchi to provide software, support and services for Hudson. Kawaguchi joins CloudBees, and will continue to grow and lead the Hudson project. The first release today from the integrated company is Nectar 1.0, formerly InfraDNA’s Certified Hudson for Continuous Integration (ICHCI) offering, which has been enhanced with new features and rebranded for CloudBees. Enhancements include VMware Virtual Machine auto configuration and deployment; enhanced backup services; pre-bundled and configured plug-ins; and an auto-update service. Nectar annual subscriptions start at $3,000 and include free minutes on CloudBees DEV@cloud service, which is currently in beta."

Congratulations!

PaaS is language specific?

2010-11-06T20:50:00.003Z

Recently I've been involved in some discussions with people on the subject of PaaS and specifically how the application language impacts it. I was surprised to hear (or read, since some of this was via email) several of the participants assume that you would need a PaaS implementation for each programming language. So that'd be a Java PaaS, a Ruby PaaS, presumably a C++ PaaS and maybe even a COBOL PaaS.

In my most diplomatic manner, I asked if certain individuals had missed the last 20+ years of middleware development; perhaps they had been stuck on some island somewhere, or maybe off on some rocket traveling close to the speed of light and while we experienced 20 years, for them only a few days have passed. See, I do like to give people the benefit of the doubt where possible!

The idea that we need to have a PaaS implementation for all possible programming languages out there (or at least those that may be used in the Cloud), is ridiculous. Think of it like this: if we can virtualize away the hardware, so it's really no longer a major issue in deployment, then we should be able to virtualize (abstract away) the infrastructure upon which the applications will rely. And yes, that infrastructure is middleware.

Oh wait ... we've done this before. Several times in fact! I won't cover them all, but let's just consider a couple of the obvious examples. First, CORBA, where services could be implemented in a range of different programming languages (e.g., C++, Java and even COBOL!) and made available to users that may be written in a completely different language. Second, Java, and specifically J(2)EE. Like it or not, despite the write once run anywhere message that came with Java, many vendors and users simply did not want to, or could not, discard their existing investments in other languages and so found ways to integrate services and components written outside of Java and often without the knowledge of the end users. For instance, there are non-Java transaction services that are integrated into application servers through the JTA. The same goes for JMS.

As an industry we have decades of experience in virtualizing the middleware layer. It doesn't matter if you're writing your applications and services in Java, Ruby or something else entirely: as long as someone provides a binding to the underlying middleware capabilities, you don't expect, and shouldn't be interested in, whether or not the middleware, or PaaS, is implemented in the same language. And in fact it shouldn't be. I'll keep saying this, but we simply cannot afford to stop the world and reinvent the middleware wheel for PaaS. We need to evolve, but we really don't need to start from scratch. I think I got my message across during the aforementioned conversations, but maybe next time I'll resort to drawing some diagrams, perhaps even with some timelines dating back to the 1960's!

Addendum: In case it wasn't clear in the above, of course there will need to be a language specific component to PaaS, but only that which is sufficient in order to allow the underlying implementations (written in whichever language is appropriate) to be interfaced with the application or service. Consider the JTA and JMS examples above.

JCP EC (re) election

2010-11-02T17:20:00.000Z

The results are in...the 2010 JCP EC Elections have officially concluded, and final results are available on jcp.org. The 2010 JCP EC Election ballot closed at midnight pacific time on 1 November. Congratulations to the new and re-elected JCP EC Members!

SE/EE EC

Ratified seats: Apache Software Foundation, Red Hat
Open Seat Election: Eclipse, Google

ME EC
Ratified seats: Research in Motion (RIM), Samsung, TOTVS
Open Seat Election: Apix, Stefano Andreani

New and re-elected members will take their seats on Tuesday, 16 November.

JCP members did not ratify Hologic for the SE/EE EC. As the JCP process document prescribes, the PMO will hold an additional ratification ballot for the remaining SE/EE seat soon.

Complete results will be available at the JCP Election page and the JCP blog later today.

Personal versus company resources

2010-11-02T15:33:00.003Z

A long time ago in a galaxy far far away ... OK, so maybe not necessarily that long ago and certainly not that far away, when work started to intrude on my personal love for computers, I made sure I had a separate machine for personal use (a desktop in those days) and one (or more) for work. That was fine for a while, but eventually it became too much of a hassle to synchronise email, source code etc. Plus, in those days there was very little distinction between my personal (for pleasure) efforts and my work. So multiple machines gave way to one machine. I also tried this with mobile phones (with one for personal use and one for work), but with much the same conclusion.

This situation existed for the best part of a decade and a half. However, in the past year I've been finding that work is intruding more and more on my leisure efforts around computing. Whether those are writing research papers or just playing around with new languages, I find it is harder to stop work (via email, IRC etc.) from distracting me. And the phone just makes it worse!

So recently I've reverted to the way things I used to do things, with a dedicated work machine that knows only about work related "stuff" (including email) and a dedicated personal machine, that knows nothing about work (and its emails). The phone problem is about to be fixed with a similar strategy. I wonder how long I'll be able to keep up this separation of concerns. But I'm looking forward to trying!

OSGi

2010-10-27T11:42:00.001+01:00

Dear OSGi Alliance Members,

Thank you all for your votes in the 2010/2011 Board elections!

Along with many returning board companies, we would like to extend a warm welcome to RedHat (Mark Little and David Bosschaert) as a new BoD member. Mark is currently CTO of JBoss, a division of Red Hat. Prior to this he was Technical Development Manager for the JBoss SOA Platform and lead of the JBossESB and JBossTS projects. David is currently Principal Engineer at JBoss, a division of Red Hat working on Open Source OSGi products. Before joining Red Hat, David was a Fellow at Progress Software and Distinguished Engineer at IONA Technologies. 

The 2011 Board of Directors will be composed as follows –

Deutsche Telekom AG – Hans-Werner Bitzer
IBM - Dan Bandera
NTT - Ryutaro Kawamura
Oracle - Anish Karmarkar
RedHat – Mark Little
Progress Software – Jamie Merrit
ProSyst Software GmbH - Susan Schwarze
SAP AG - Karsten Schmidt
Software AG - Prasad Yendluri
Telcordia Technologies - Stan Moyer
VMWare (SpringSource) - Peter Cooper-Ellis

We are looking forward to a productive year 2011!

Paper reviews

2010-10-25T15:30:00.003+01:00

After a fairly hectic week, this week begins with no company email (don't ask!) So this gives me a bit more time to do my paper reviewing for the Workshop on Engineering Service-Oriented Applications. I've got a couple of work on and they appear interesting at first glance. A happy alternative to the last few weeks.

Timezone issues

2010-10-04T06:39:00.002+01:00

The past couple of weeks have been hectic. First I was at JavaOne, then I spent time around the west coast visiting customers and partners (talking a lot about Cloud, funnily enough). Then it was a red-eye to Boston and meetings for the rest of the week, before getting home in time for the weekend. Several timezones over two weeks played havoc with me and I missed a few calls due to my forgetting where in the world I was!

This week is slightly better, with meetings in Paris tomorrow, then Berlin for the SOA Symposium (where I'm giving a couple of presentations) and JUDCon (no planned sessions for me to give, though I may do a lightning talk). Back home in time for the weekend again. The next couple of weeks should be in and around our Newcastle offices! And maybe in between all of this I'll get a chance to do some coding!

Blast from the past

2010-09-14T13:15:00.001+01:00

I had no idea the University was scanning in old theses. I haven't seen this one for almost 20 years!

Cloud and multitenancy

2010-09-08T14:12:00.002+01:00

Over the past year or so I've been doing a lot of thinking about various aspects of cloud. One of the ones I keep coming back to is the issue of multi-tenancy. Many years ago, when I was formulating the categorization of transactional replication strategies, we found that splitting up the object server (methods) from the state and allowing each to be replicated independently, gave the ability to express everything necessary to cover the range of replica consistency protocols from passive through active. Sharing of the executable versus sharing of the state is based on aspects such as determinism of execution (passive is the only option in some cases) and speed of fail-over (active tends to do much better).

So what has this to do with multitenancy? Well I've been thinking about what it means to have a true multitenant application and hence PaaS. Some people seem to suggest that multitenancy is somehow new, complex or the domain of a new breed of engineers and vendors. But if you think about it, we've been using multitenant environments for years. Your operating system is multitenant, with multiple applications resident and often running concurrently, perhaps modifying shared data structures as a result. Even your modest Web server can be considered multitenant. And there are a range of strategies for achieving multitenancy based on a similar server/state split. Therefore, whether you're a SaaS implementer or a PaaS architect, the same factors come into play. And critically for SaaS implementers, if your PaaS doesn't support these things then you're going to have to!

In terms of PaaS, there are really 3 components that can be played with in terms of multitenancy and application and data deployment. These are the VM, the application server (container of business logic) and the data (database, file system etc.) For instance, you could have each tenant in a separate application server but running on the same VM, with data split between different database instances. Or you could have each tenant in the same application server on the same VM, with data in the same database, perhaps split on different tables. (Other options and configurations exist, of course.)

Now all of these various combinations have more or less been around before, as I said earlier. The big problem though has been around ease of use. I've written enough Unix kernel services before, for instance, to know most of the ins-and-outs of sharing state without causing the operating system to crash, and the best way to use pthreads or memory mapped files in a shared environment, but it's not always intuitive or based on well documented processes. This is precisely where a PaaS fits in: it must support the widest range of approaches and in a way that does not require the SaaS developer to have to worry about them. We can learn a lot from what's been done in the past around the intricacies of achieving multitenancy, but we do need to make it far more consumable than has perhaps been the case so far.

Interesting new paper on transactions

2010-09-07T11:45:00.002+01:00

I met Daniel Abadi at HPTS 2009 last year, where he presented on HadoopDB. Very interesting and a good presenter. So it's good to see his latest paper on determinism and transactions in database systems. It's a good read and particularly for me because it mixes the two areas that have always been my interests: transactions and replication. The authors have some good things to say about NoSQL, but specifically around relaxing ACID semantics, the trade-offs that incurs and how perhaps there is an alternative. Again, this is an area I've had a bit to do with over the past few decades. I'll have to think about how and whether this is applicable to some of the work we're doing at the moment in large scale data grids.

Coming of age?

2010-08-30T19:14:00.002+01:00

Thousands of years ago the coming of age ritual involved hunting and killing (e.g., mammoths or dinosaurs, depending upon which film you believe). Due to changes in a range of things, including society and the fact that mammoths (as well as dinosaurs) died out (maybe related to hunting, strangely enough) the rite of passage changed.

In our household one aspect of our version of this ritual is introducing the kids (my 8 year old now) to the all time great movies. Several weeks ago it was Lord of the Rings, which went down really well. This weekend we started into Star Wars. Of course the first question was which order to play them? Against my better judgement we went with the chronological order, i.e., Episode 1 first. The first two movies went down well with him, though the third was more of a slog, but of course the best movies are yet to come.

However, I realised that although it's been about 8 years since I've watched the movies, two things remain a constant for me: the midichlorian rubbish detracts from the story (what was George Lucas thinking?!) and I still can't stand Ja Ja Binks! But my son loved him! If he loves the Ewoks then all is lost and I think I'll fail him on this rite of passage!

Long weekend coming up

2010-08-27T16:17:00.002+01:00

It's a national holiday here on Monday, so this is a nice long weekend. Unlike my 2 week vacation which only ended at the start of last week, I've decided to not touch anything remotely work related until Tuesday (that holiday turned out to be > 50% work!) Well that's the theory at least. I know there may be some pressure to bend that rule slightly, so we'll wait and see!

CloudBees

2010-08-27T11:09:00.002+01:00

It's been 18 months since Sacha left JBoss and I took over. He said he was going to take time off to enjoy being with his family and (then) new baby daughter. However, I think many of us knew that at the time it wouldn't be long before he was back doing something interested. So it's really good to be able to announce that that effort is called CloudBees and they've officially launched! Hudson as a Service (HaaS) is a really good idea! Coincidentally it's something that JBoss and Arjuna separately considered at one time or another with their/our Distributed Test Framework.

Good luck Sacha and team!

BBC Micro making a comeback?

2010-08-25T12:11:00.002+01:00

I loved this article! It brought back a lot of memories from when I was programming in BBC Basic. I upgraded my machine to support Metacomco's Pascal and C as well. Lots of fun and I like to think the "hardships" that the students of today mentioned helped to make me appreciate what it takes to write code in less than 32K of memory!

Classic C++ textbook

2010-08-18T18:49:00.002+01:00

Every now and again I have to go through my cache of books and box some of them up for storage. This time it was some of my old text books from university, but while going through the process I went through all of my C++ related books. One of the best I've ever read is Barton and Nackman. I got this book just after it came out (I think I got it just after visiting Graeme at Transarc.) It's a wonderful book and reading the Amazon comments afterwards it's good to see that I'm not alone in thinking that. If you're a C++ programmer then you should definitely check it out.

Private Clouds?

2010-08-09T20:35:00.002+01:00

I've known Werner Vogels for several decades, ever since we were both doing our PhDs. Like all good friends and scientists, we don't always agree on everything. Case in point is that Werner doesn't believe Private Clouds are clouds and I think his arguments against are artificial and short sighted. Now of course you could say that he and I take our perspectives on this debate precisely because of our employers. However, that's wrong, at least where I'm concerned.

As I said earlier this year, I think that today's definition of Cloud is limiting and emphasizes Public Cloud precisely because that's what most people have access to. But I also believe that Public Clouds are not going to be as important in the future. Cloud is a natural evolution of hardware and software (middleware) but if you liken the roadmap for Cloud to that of cars, today's Cloud's are like the Model T: showing everyone the potential, but not available to the masses. We should be looking at the equivalent of the next hundred years of evolution in automotive technologies as far as Cloud is concerned, bringing their benefits to the masses (of people and workloads).

This development has to include Private Clouds (which, contrary to what Werner states, don't necessitate corporations having to buy more hardware), but so much more. The true cloud is the collection of processors that exist virtually everywhere you turn, including mobile devices and sensors. That's where the definition of Cloud must go. In many ways it's returning Cloud to one of its progenitors, ubiquitous computing. By that point there won't be a Public, Private or Personal Cloud, there'll be "just" Cloud (or maybe some other term). Where your application is hosted will still remain important, but not because of any artificial reasons due to words such as 'private' or 'public'.

Why JeAS?

2010-07-31T15:34:00.002+01:00

I've been saying for a while that the last thing the industry needs is a return the days of vendor lock-in or somehow resetting the clock on the past 40+ years of middleware and rediscovering it all again. That's why I believe we have to leverage what we've got. Yes, it needs to morph and evolve, but we should start using (reusing) existing investments. Furthermore, I believe that if the ideals behind Cloud are to be realised then they must start by tackling existing workloads.

This is why the application server (no formal definition in this article) is the right vehicle for applications. It doesn't matter whether you just consider this to be Tomcat or your favourite application server (JBoss, of course!), whatever is hosting your important applications today and which your developers are comfortable with, that's the basis of your own PaaS requirements. Therefore, that has to be the basis for PaaS wherever you may want to deploy in the future. But even today you often find that your application server may be providing more functionality than you need, at least initially. Just considering Java Enterprise Edition for a moment, that's one of the reasons behind the introduction of profiles (which always reminded me of the Core Services Framework Bluestone/HP pushed back in 2000, driven by my friend and co-author Jon Maron).

So this is where I come from when I mention Just Enough Application Server: when deploying into a PaaS you really need support from your underlying application server to ensure that just enough is deployed and no more. Ideally this should be done automatically as your appliance is generated, but static is OK too. Throw in a bit of autonomous monitoring and management in case things change on the fly (application and object migration is a distinct possibility, so the underlying infrastructure/application server needs to be able to cope), and you've got yourself one super sleek PaaS.

JeAS

2010-07-31T15:17:00.001+01:00

First there was JeOS, which makes sense for IaaS. So what's the equivalent for PaaS? Well I reckon it's Just Enough Application Server (JeAS perhaps?) More on this subject soon!

JCP Award Nominations are open

2010-07-29T11:02:00.001+01:00

Cross linking to the award notification.

Has Java reached a point of inflection?

2010-07-18T21:51:00.002+01:00

I've been wondering about this for a while. As far as languages go, Java has experienced a good run, remaining in the number 1 or 2 spot for the better part of a decade. The language came along as the Web was really growing from its fairly basic roots as it's arguable that Java influenced the development of it more than many languages. It certainly took over from the likes of Pascal and C/C++ in universities and as a result most new software developers have more than a passing knowledge of the language. Of course it's never been a perfect language (I'm not sure such a thing will ever exist, except for very domain-specific languages); it's also never been my favourite language (C++ still holds that position.) However, I think that Java has had an overall positive affect on the industry.

The Java platform (formerly known as J2EE) took a few years to emerge after the first releases of Java (aka Oak) and initially competed with CORBA in the non-Microsoft camp. Once it was clear that J2EE would dominate, CORBA tried to embrace it more closely (the CORBA Component Model, for instance) but was never quite the force it once was. However, J2EE wasn't perfect and a lot of that could be traced to its CORBA roots. It wasn't really until EE5 and EE6 that it managed to escape those shackles, but even despite those problems it dominated the industry. Of course it's precisely because of some of these issues that frameworks such as Spring sprang (!) up, but even then a lot of those deployments ran on J2EE to simplify development.

During its life Sun was a pretty good custodian of the language and the platform. Yes there were issues, particularly when Sun moved from being a neutral party to one that competed in the vendor landscape. But when you think about how one other company in a similar position handled a similar position in the 80's and 90's, things could have been a lot less open. In fact I'm certain that the success of both the language and the platform is due in no small part to this relative openness that Sun managed to juggle, despite their conflicts of interest. Towards the end of their life as an independent company, with the likes of the Apache License issue, it was obvious that Sun couldn't quite make the necessary leap that was/is required to continue the dominance of the language/platform (and you could argue to revitalize it).

And of course that brings us to the present and Oracle. If Java was at a point of inflection prior to their acquisition of Sun, it continues to be there today many months afterwards. Myself and others have argued that this is a good opportunity for Oracle to "do the right thing" and make good on their previous statements in that regard. To continue without such change risks pushing us over that tipping point, with fragmentation, vendor specific options and the end of the world as we know it. (OK, that last point is unlikely to happen!) As I've been saying around Cloud, we really shouldn't be looking at turning back the clock: it won't do anyone, including Oracle, any good.

Now maybe Oracle are considering making some positive announcements at the forthcoming JavaOne. I hope so. Continuing to make Java open and fast moving will benefit everyone, customers and vendors alike. And hopefully Oracle can make the leap that Sun never seemed to be able to make. What's that they say about Nixon and China?

Red Hat/Newcastle University research day

2010-07-16T18:21:00.002+01:00

Just back from the first official research day with Newcastle University and it was good. We covered a lot of short and long term research areas, including fault tolerance, scalability, event processing and policy definition/management. It all had a very heavy practical slant to it, which is event better given that we're hoping to see a lot of this come through into various JBoss/Red Hat projects and products eventually. All in all it was a good day and hopefully next time we'll take a couple of days so we can delve into things in much more detail. But for now I've got to go through my notes and start working on getting these R&D efforts underway!

JUDCon Europe 2010

2010-07-10T09:32:00.002+01:00

I've mentioned JUDCon before, and it's only been a couple of weeks since we had the very first event in Boston, which went very well. However, no time to relax since it was always our intention to have a couple of these a year and it's surprising how much lead time you need to make it happen. So we've decided on the dates and location for the European event: 7th and 8th of October in Berlin. Next up is figuring out the themes for the tracks and then we'll open up the call for presentations.

Cloud-TM project

2010-07-08T13:25:00.002+01:00

We're involved with a new EU Research project called Cloud-TM. Should be some good opportunities for long term research and development, whilst at the same time having strong industrial relevance. I'm looking forward to the kick-off meeting next week in Portugal!

DO'h!!

2010-06-23T16:18:00.003+01:00

I've given countless presentations at many different events over the years and usually I'll either be on time or run slightly over time. On a few occasions I've finished early, but never have I finished 20 minutes early thinking that I was over time! I started my first JBoss World presentation this year at 10:20am and got into my stride. I think I got too caught up in what I was saying because at some point I looked down at my watch and noticed it was 10:50am. I obviously forgot what time I'd started because the only thought that ran through my mind was "Oh sh*t, where did the time go, I've only got 10 minutes left!" I managed to get through the remaining 10 slides or so by skipping some (fortunately they'll all be available on the web) and got into Q&A time, still blissfully unaware that I still had 20 minutes remaining. In fact it wasn't until I was walking away that someone pointed it out! So, if you were in that session I definitely apologise for rushing needlessly!

MW4SOC CFP

2010-06-22T14:11:00.001+01:00

CALL FOR PAPERS
===============

+--------------------------------------------------------+
| 5th Middleware for Service-Oriented Computing (MW4SOC) |
| Workshop at the ACM/IFIP/USENIX Middleware Conference |
+--------------------------------------------------------+

Nov 29 Dec 3, 2010
Bangalore, India
http://www.dedisys.org/mw4soc10/

This workshop has its own ISBN and will be included in the ACM digital library.

Important Dates
===============
Paper submission: August 1, 2010
Author notification: September 15, 2010
Camera-ready copies: October 1, 2010
Workshop date: November 30, 2010

Call details
============
The initial visionary promise of Service Oriented Computing (SOC) was a world of cooperating services being loosely coupled to flexibly create dynamic business processes and agile applications that may span organisations and heterogeneous computing platforms but can nevertheless adapt quickly and autonomously to changes of requirements or context. Today, the influence of SOC goes far beyond the initial concepts of the original disciplines that spawned it. Many would argue that areas like business process modelling and management, Web2.0-style applications, data as a service, and even cloud computing emerge mainly due to the shift in paradigm towards SOC. Nevertheless, there is still a strong need to merge technology with an understanding of business processes and organizational structures.

While the immediate need of middleware support for SOC is evident, current approaches and solutions still fall short by primarily providing support for only the intra-enterprise aspect of SOC and do not sufficiently address issues such as service discovery, re-use, re-purpose, composition and aggregation support, service management, monitoring, and deployment and maintenance of large-scale heterogeneous infrastructures and applications. Moreover, quality properties (in particular dependability and security) need to be addressed not only by interfacing and communication standards, but also in terms of actual architectures, mechanisms, protocols, and algorithms. Challenges are the administrative heterogeneity, the loose coupling between coarse-grained operations and long-running interactions, high dynamicity, and the required flexibility during run-time. Recently, massive-scale and mobility were added to the challenges for Middleware for SOC.

These considerations also lead to the question to what extent service-orientation at the middleware layer itself is beneficial (or not). Recently emerging "Infrastructure as a Service" and "Platform as a Service" offerings, from providers like Amazon, Google, IBM, Microsoft, or from the open source community, support this trend towards cloud computing which provides corresponding services that can be purchased and consumed over the Internet. However, providing end-to-end properties and addressing cross-cutting concerns like dependability, security, and performance in cross-organizational SOC is a particular challenge and the limits and benefits thereof have still to be investigated.

The workshop consequently welcomes contributions on how specifically service oriented middleware can address the above challenges, to what extent it has to be service oriented by itself, and in particular how quality properties are supported.

Topics of interest
==================
* Architectures and platforms for Middleware for SOC.
* Core Middleware support for deployment, composition, and interaction.
* Integration of SLA (service level agreement) and/or technical policy support through middleware.
* Middleware support for service management, maintenance, monitoring, and control.
* Middleware support for integration of business functions and organizational structures into Service oriented Systems (SOS).
* Evaluation and experience reports of middleware for SOC and service oriented middleware.

Workshop co-chairs
===============
Karl M. Göschka (chair)
Schahram Dustdar
Frank Leymann
Helen Paik

Organizational chair
====================
Lorenz Froihofer, mw4soc@dedisys.org

Program committee
=================
Paul Brebner, NICTA (Australia)
Gianpaolo Cugola, Politecnico di Milano (Italy)
Walid Gaaloul, Institut Telecom (France)
Harald C. Gall, Universität Zürich (Switzerland)
Nikolaos Georgantas, INRIA (France)
Chirine Ghedira, Univ. of Lyon I (France)
Svein Hallsteinsen, SINTEF (Norway)
Yanbo Han, ICT Chinese Academy of Sciences (China)
Valérie Issarny, INRIA (France)
Mehdi Jazayeri, Università della Svizzera Italiana (Switzerland)
Bernd Krämer, University of Hagen (Germany)
Mark Little, JBoss (USA)
Heiko Ludwig, IBM Research (USA)
Hamid Reza Motahari Nezhad, HP Labs (USA)
Nanjangud C. Narendra, IBM Research (India)
Rui Oliveira, Universidade do Minho (Portugal)
Cesare Pautasso, Università della Svizzera Italiana (Switzerland)
Fernando Pedone, Università della Svizzera Italiana (Switzerland)
Jose Pereira, Universidade do Minho (Portugal)
Florian Rosenberg, Vienna University of Technology (Austria)
Giovanni Russello, Create-Net (Italy)
Regis Saint-Paul, CREATE-NET (Italy)
Dietmar Schreiner, Vienna University of Technology (Austria)
Bruno Schulze, National Lab for Scientific Computing (Brazil)
Francois Taiani, Lancaster University (UK)
Aad van Moorsel, University of Newcastle (UK)
Roman Vitenberg, University of Oslo (Norway)
Michael Zapf, Universität Kassel (Germany)
Liming Zhu, NICTA (Australia)

JBossWorld and JUDCon

2010-06-19T09:28:00.003+01:00

Off to Boston tomorrow for JBossWorld and JUDCon. The former is always a good event, but it's really the latter that I'm looking forward to the most, since it's the first ever one and it's taken us a while to organize. I'm already working on the European version that'll be coming in a few months time so hope to get some constructive feedback from the people to attend in the coming few days. And for my long flight to Boston I'm having a complete break and finishing reviewing someone's PhD thesis.