December 30, 2006

The SuperHero Test

I saw this on Allessandro Iob's blog. I too am Iron Man. Maybe I should start using IronPython?

Your results:
You are Iron Man

Iron Man
The Flash
Wonder Woman
Green Lantern
Inventor. Businessman. Genius.

Click here to take the "Which Superhero am I?" quiz...


I see Blogger have released their beta developments into production. I can't help wondering if that's why my previous posting doesn't seem to have made it through RSS feeds and into the places it usually appears. It's not every day something so noteworthy happens.

December 29, 2006


Well, thanks to coralpoetry for pointing out this has become a blog of note, presumably the last of 2006. I suppose this might be more humbling if there were published criteria for what makes a blog noteworthy, or if I had been aware of this feature before it linked to ... for Some Value of Magic. Another ten seconds of my fifteen minutes of fame?

Acknowledgements of any sort are encouraging, though. Like the old saying about bad publicity, for a minor blog there's no such thing as unwelcome atttention! So many thanks to whoever at Blogger (Google) put me on that list and to anyone else who happens to read this blog.

Because of the linkage I suspect that a small spike in readership is likely to occur, so let me take this opportunity to wish all fellow-members of the blogosphere (dreadful word) and all Holden Web customers a happy and prosperous new year. 2006 (and especially the latter part of it) has been somewhat traumatic for various reasons, so here's hoping for a smoother 2007.

Finally, while I have your attention, let me point you to Pass IT On, my favourite charity. Martha and Sandy's dedication to their goal of providing computer equipment to the disabled is single-minded, and I wish I could do more to help them. If Santa Claus has brought you a new computer please consider donating your old one. They also need cash support to help them become a free-standing organisation this year, so you can give them money if you don't have a computer to spare. Good luck to all at Pass IT On.

December 18, 2006

ZFS: "Probably more abuse in 20 seconds than you'd see in a lifetime"

I've been reading (thanks to Brett Cannon) about the Zettabyte File System (ZFS) - an open source project from Sun Microsystems that seems to offer real opportunities to take proper advantage of both SAN and virtualization technologies. If you want to know what a zettabyte is then as usual the Wikipedia is reliable on technical matters (and no, I had never run across the term before).

Brett was simply happy that Apple announced the inclusion of ZFS into the Leopard (OS X 10.5) distribution. I was interested because Sun developers were taking an interest in advanced filesystems even back when I used to work there - they produced the Translucent File System (TFS), which was a copy-on-write mechanism to allow users to share a common source pool and keep their own changes.

One of the problems with TFS was its need for kernel integration (in those days even the windowing system was integrated into the kernel). Another issue arose when a user base their TFS on another TFS which was based on a third TFS which ... effectively it implemented an copy-on-write inheritance mechanism, but efficiency could drop quite rapidly with multiple layers.

Unlike TFS, ZFS can run in either kernel or user mode, and the nightly testing appears to twist the filesystem in every possible direction simultaneously (hence the title of this blog entry). Here's a list of what goes on in parallel in each nightly test:

? Read, write, create, and delete files and directories
? Create and destroy entire filesystems and storage pools
? Turn compression on and off (while filesystem is active)
? Change checksum algorithm (while filesystem is active)
? Add and remove devices (while pool is active)
? Change I/O caching and scheduling policies (while pool is active)
? Scribble random garbage on one side of live mirror to test self-healing data
? Force violent crashes to simulate power loss, then verify pool integrity

So, it would appear that ZFS is a worthy successor to TFS and much more besides, as you will find out if you too read the slide show. I haven't looked at the license yet, but it does appear that under Johnathan Schwartz's direction Sun might be beginning to find its way in the open source world of the 21st century, despite the amusing graphic that Eric Bangeman produced when Scott McNealy resigned. Maybe I should buy some stock again. Maybe we all should.

December 12, 2006

Lies, Damned Lies and Baggage Claim Call Centres

I travel quite a lot, and up until now I have been lucky. Bags have been lost from time to time, but they have always made their way back to me, usually within 24 hours. I understand that bags can get lost occasionally, but the frustrating thing last time this happened was the complete absence of any reliable information.

I flew from Edinburgh to London Heathrow, then onwards to Washington Dulles where I was incorrectly instructed to enter the USA through the transit lounge. Since my flight to New York's La Guardia was on a separate reservation and my bag had only been checked through to Washington this put me in the wrong place to reclaim it, and trriggered what I would call a comedy of errors if there was anything the least bit funny about it. My bag and I were both in Dulles, but United were unable to reunite us. I was initially assured that the bag would join me on the flight to La Guardia but, inevitably, I arrived and it didn't.

So I registered a claim and went to my accommodation. It took forty-eight hours and ten 'phone calls before I was finally able to wear the clothes I had brought with me. For most of that time United's web site was telling me that the bag had been found and that it would be sent to New York on a non-existent flight shortly before I landed at Washington!

Talking to other travellers, the general impression is that baggage "help" lines are uniformly bad. My own experience was certainly terrible: I could easily have believe that there was no computer-based information system at all behind the scenes, as the different people I spoke to gave me completely different and inconsistent stories each time I called. The responses almost seemed calculated to inflame. I was particularly incensed by a conversation with one woman who, when I called back as requested after waiting two hours, insisted that I had only called thirty minutes previously, and that I should wait until next morning before calling again. It's not usually considered good customer service to call the customer a liar. The different stories I was told about my luggage might as well have been chosen at random.

Under these circumstances the airlines would do better to dispense with the call centres completely and replace them with a recording saying "Our staff are working to restore your lost bag. Thank you for your patience". This would be less irritating than the nonsense I had to put up with, would have taken up far less of my time, and would hopefully reduce costs and allow the airlines to invest a bit more in relocating and delivering lost bags.

And now, if you'll excuse me, I have to send a claim for reimbursement to United.

December 1, 2006

Blogger on a Nokia 770

Well, I find myself with only a Nokia 770 Internet tablet to access the 'Net, so I thought I'd see how easy it was to create a blog entry. The typing is less than terrific through the hunt-and-peck on-screen keyboard, but so far I haven't been able to get my snazzy laser-projection VKB virtual keyboard to work reliably with the Nokia, so I have to be satisfied with the standard mechanism..

One rather strange feature of the interface seen through the Nokia is the invisibility of the title field. I see in the postings list that I've somehow managed to call it JU, but I really can't see how to change it. Maybe I'll change it later.

I seem to remember that the AJAX functionality used to work, but that's not the case since I upgraded the operating system. Maybe there's some setting that I need to update, but if so it eludes me. Anyway, this has taken quite long enough so I'll save the post as a draft and put the title right before I post it.

Browser Statistics (Hello, Robots)

During the current statistics trawl I started to wonder which browser technologies dominated among the visitors to the Holden Web site. November was an interesting month because both Microsoft and the Mozilla team released new products.

Here is typical information for the top ten client programs. Unlike previous statistics, Firefox users account for almost a half of the traffic to the site - usually Internet Explorer leads the pack with about 30%, but in November it was relegated to third position.

Internet Explorer 7.0 currently accounts for 2% of traffic, the first time it's appeared in the stats. The thing I found most surprising was the fact that more Firefox users were using the recently-released 2.0 version than anything else. 2% of users still use Firefox 1.0.

Rather less delightful is the fact that 20% of site traffic is spidering (though how come Yahoo has to crawl so much more aggressively than anybody else is beyond me). Perhaps the real message is that I need to put some more compelling content on the site!

A Tip o' the Hat to Ron Stephens

Looking at my web site statistics the other day I discovered, as you might expect, that the majority of referrals were coming from Google. However the notable second source is Ron Stephens' Awaretek site. Ron has been quietly generating Python reference materials and producing a Python podcast for years now, with vary little in the way of public acknowledgement. So thanks, Ron, keep up the good work!

Database API Tutorial at PyCon TX 2007

The list of PyCon tutorial offerings has now been finalised, and I'm happy to say that my Database API proposal has been accepted. Once again there is a great line-up of tutorials. It must have been hard for the program committee to choose this year's line-up since most of the offerings were strong and from well-respected speakers.

This doesn't guarantee that any tutorial will run: there have to be enough sign-ups for that to happen. This year there is also a tutorial on SQLAlchemy, and it looks as though the schedule will allow people wnating to understand how to use databases in Python to go through the DB API in the morning and then learn SQL Alchemy in the afternoon. I'll be conferring with Jonathan Ellis to make sure that I cover any necessary background for those who want to attend both.

I'm hoping that my tutorial will be well-received — last year's filled the room, and helped me fund my attendance at PyCon. It's always good to have guidance from students in advance telling me what their "hot-button" items are. If you're thinking of attending you can use this page to provide guidance on the content you'd like to see.