Friday, October 17, 2008

New Macs

I've been a Mac user for a few years (keep promising myself that I'll return to Linux one day), so I was looking forward to the announcement of new Macs. But I obviously missed something because I'm not really impressed with what I've seen. No button on the track-pad? No 1900x1200 resolution? Slightly improved performance. But gone is the metal screen surround, to be replaced by black plastic?! I'm not sure what I expected from Apple, but it wasn't this. Plus, maybe the thing will look better when viewed up close rather than through a web page. If the new design does get around the erosion problem then it'll be worth an upgrade eventually.

Thursday, October 16, 2008

Transactive Memory

I've been doing some research on Software Transactional Memory recently and as a result started to read about Transactive Memory. Now it quickly became apparent that the two things are unrelated, but I found transactive memory to be very interesting (not to indicate that STM isn't interesting!) Put simply, transactive memory is the name for the process whereby people selectively remember things and rely on their relationships with other people, or other things, to remember everything else. So for example, you don't remember every single phone number for everyone you know: you're selective (because that's how the brain works) and remember the "top" 6 or 7, but will probably rely on a telephone book or a PDA for the others. In the home, you may not remember how all of your friends are related to one another, maybe relying on your partner to do that. If you are a technophobe then you may rely on someone in your family to program the DVD player so you don't have to remember how to do it. If you've got kids then you may rely on your partner to do the bulk of their welfare. And the list goes on.

So what has this to do with STM? Well as I said at the start, absolutely nothing. But it does have relevancy to something else I've been interested in for the past few years: repositories. I've always believed that systems such as repositories are better implemented in a federated manner: they scale much better. This means that although you may have a logical notion of a repository, each physical instance is responsible for some different aspect(s) of the whole "mind". This is important because, for example, how you store and index service binaries is different to how you would store and index service contracts, or workflow definitions etc. In this kind of set up if you ask one repository instance "do you know about X" it should say either "no, but I know a man who does" or "no, but hold on and I'll get the answer for you". I'd never been able to put a name to the approach (beyond federation), but it seems to me that this is precisely transitive memory from a software system. DNS works in the same way.

Wednesday, October 08, 2008

CSP book available for free

I'll never know how I missed this announcement from 4 years ago, but the original CSP book is one of the most dog-eared in my library. If you don't have a copy, then I encourage you to download this and read it: it's as applicable today as it was 20 years ago (if not more so!)

To Twitter or not to Twitter?

A number of friends are "on" Twitter and apparently I should be too. I'm not quite sure why though. If blogging is anything to go by, it'll probably take me a couple of years to get round to it.

Nice article on REST

I haven't blogged much recently because I really haven't had the time. The same is true at the moment, since I'm sitting in yet another airport lounge, this time coming back from the first SOA Symposium (hopefully there'll be a blog entry or two from me on that subject later). But I wanted to say that I really enjoyed the latest article from Jim, Savas and Ian. It's been a few years since Jim and Savas worked for me and blogs/articles are often the only regular way we keep in touch. Nice work guys!