Archive for July, 2005
Back in Dublin
Well, I’m back from Apachecon and working hard at bringing the new ftp.heanet.ie online. As promised the I’ve put the slides up at http://www.stdlib.net/~colmmacc/Apachecon-EU2005/.
Already discussions had at the ‘con have outdated the presentation. Yesterday I checked out the latest httpd-2.2 branch from subversion (brached by Paul Querna last week) and set about benchmarking them on Itanium. Using the linux 2.6 kernel and the latest glibc NPTL the threaded worker mpm is coming out faster for me. Coping with about 8000 requests per second compared to prefork’s 6200. Though I’ve yet to fire up autobench and do some stress-testing, these numbers are just the response rates. Currently the machine is filling it’s disks as fast as I can synch content, but it’s still going to take a few days.
I’m also finally working on adding graceful-stop functionality to httpd, so that I can upgrade it without terminating the downloads of several hundred people. And on our system we get dialup users downloading ISO’s, so they get annoyed at that. The graceful-stop functionality itself is relatively trivial to add, the problem is signalling the stop. httpd uses plain old kill-type signaling, and there’s a slight problem of having run out of usable signals. SIGUSR1 is taken for graceful-restart, SIGUSR2 breaks threading on some platforms, strace/truss on others and the purify utility anywhere. SIGWINCH is used already for graceful-restart on Linux kernels which had userland threading. So, adding the functionality of a graceful-stop might meen a complete overhaul of the lowlevel IPC, oh the joy.
The rumour mill has it that this week will finally see an update for Apple’s laptop line, which means I might be buying my second new laptop in only 6 weeks, but since my parents want a laptop and my Dad has been eyeing my widescreen Vaio, it will find a good home.
And lastly, I’m off to Cork this weekend with Noirin, for what should be fun and luxurious long weekend. Definitely looking forward to that.
@ Apachecon
Well, I arrived at Apachecon yesterday, the weather here in Stuttgart is great and from my first impressions it seems like a very nice City. Found the conference venue easily enough and it is very impressive. As is my cavernous Hotel room.
Check out the ApacheconEU2005 Flickr tag for lots of great photos, like this one of the hall being used for Keynotes, and where I’ll be giving the Scaling Apache talk tomorrow morning.
The Networking guys have got a great network up and running, and the turnaround from asking for IPv6 connectivity, to it being fully working was only a few hours. We even managed to confirm that the connectivity should work for a demo last night at the hackathon.
I’ve added and changed a few slides from the presentation, as well as adding a slide recommending other talks at the con. Seeing the first keynotes on a cinema-sized widescreen means I’ve also made all of the graphs full-screen and tweaked their contrast. I’m going to do a little more work on it and then I should be able to post it up here. I’m not sure if I’ll have the time to make the corresponding changes the LaTeX paper by tomorrow.
The flight here was interesting, it’s the first time I’ve flown with Hapag-LLoyd Express (The German Ryanair, roughly), and they do things a little differently. The first thing you notice is that inside it’s like a Mercedez benz, all faux-leather seats, and fancy extras like the flip down LCD’s which arn’t that common on short-haul (it shows a map tracking flight progress, when in flight). The airline either has a policy of recruiting from families, or simply clones their flight crew. All-blonde, all almost indistinguishable (down to having their hair tied in extactly the same way with the same number of those hair-elsatic-things aka scrunchies/bobbins/whatever).
But the biggest difference is how they fly. I don’t know if it’s German efficiency, or if they interchange freight and passengers so frequently the pilots don’t know the difference, but it was much more dynamic than your standard inferior airline. The ascent was rapid, we went straight up at 45 degrees, half way through we also banked hard to the left (again about 45 degrees) to face the right direction, and within 3 minutes (about 10 minutes ealier than I’m used to) of take off the seatbelt sign was off. Excellent, none of the sissy yaw turning, and hell when descing between flight paths why do it gently when you can just drop out of the sky!
Don’t get me wrong, it was comfortable and everyone seemed used to it, but it was different to fly with an airline who seem more concerned with getting there quickly than not listing beyond 5 degrees because about 10ml of someones Coffee might spill.
In other, unrelated news, planet.redbrick.dcu.ie is now up and running, with Cammy and Cokane also working hard to make it happen.
Google Maps API and that last post
As I’ve pretty quickly found out, the restrictions in the Google Maps API are fairly pants for any kind of map-blogging, or anything that uses dynamic url’s. The Google maps key is tied to a specific domain and “directory”. So; a map embedded at example.com/foo/ will work, but not www.example.com/foo/ or example.com/foo/bar/.
So, while you can see the map just fine if you go to http://www.stdlib.net/~colmmacc/, you can not see it from the permalink page, or in any RSS reader.
Uggh, why didn’t they just use a simple per-user key like the other Google API’s! Apparantly they are working on it. When it’s fixed I’ll make the change. In the meantime, I’ll see if I can use mod_rewrite to get around it.
Oh also, if you’re trying to make embedded Google maps default to satellite view there’s a bug in the API, instead of using:
1 | map.setMapType(G_SATELLITE_TYPE); |
You have to use:
1 | map.setMapType(_SATELLITE_TYPE); |
That took a while to find.
Update: Oh and it seems the embedded google map crashes IE, I’m impressed. Just use mozilla.
Update 2: Solved the problem a really nasty way. The google map is now embedded in its own html page, which in turn is embedded using an iframe. *shudder*, but it works.
Hidden Dublin
Posted on July 13, 2005, under photography.
It’s hard to believe, but I took this photo right in the heart of suburban Dublin;
If I’d pointed the camera only a few degrees to the left there’d be a shot of the entire Westlink toll-bridge. It’s a wierd photo, but it’s one of my favourites. I took it in September 2003, and the colours of the trees really set off the red of the boarded-up parts of the house. The grey-ish sky against Farmleigh clock-tower is a bit disconcerting, so I always find it an interesting picture to look at.
There’s actually three sets of trees in the photo, some before the Liffey, some before St. Martin’s Road and then the trees in the distance are all in the Phoenix Park or on the Farmleigh estate. The Google maps satellite imagery shows pretty perfectly where I took the shot, the house in question is right at the centre of that link. If you scroll to the top right you can see the bands of trees (and the gaps between them) and the Farmleigh estate. Here’s my attempt at illustrating this using the Google Maps API;
You should be able to click on the markers for some information.
It’s hard to believe that such a beautiful area is only 5 minutes walk from Liffey Valley shopping centre. But it is, it’s behind Palmerstown Village, and it’s a good few acres of empty land, leading right down to the river. It has some great walkways, although you’ll have to deal with the odd few burnt-out car. If you’re in West Dublin, I definitely recommend a visit!
New Server, New Paper
A while ago, I promised I’d reveal the new ftp.heanet.ie specs, and since someone reminded me of this today, here they are;
- Dell 7250
- Dual 1.5Ghz Itanium
- 32GB of RAM
- 4x 1Gbit/sec ethernet (load balanced)
- 145GB of U320 15k RPM RAID-0 in a Powervault as an intermediate cache layer
- 3x 4.4TB SATA – SCSI RAID5 enclosures, from Fibrenetix
Before anyone points it out, we know all about Itanium and its wackiness, but we got a price for this system we could not refuse (If you price just the memory on Crucial, you get a higher number than we paid for the entire box) and we’ve done our homework.
There’ll be much more detail coming soon. I’m going to rewrite my Apachecon talk and paper in light of this, as well as in light of the upcoming donation of the mod_ftp code to the ASF from Covalent.
Strictly speaking, I’m probably supposed to give the talk that’s on the ‘con CD, but I figure I’ll ask the organisers if I can give the audience the option on the day to have the old talk or the new talk, and point them at url’s for the paper. It won’t be very different, but at the same time, the two months since the presentation/handout submission have also coincided with some big developments.
Either way, the new papers won’t go to waste, it’s lined up for SAGE-IE next year.
And with that, I should mention that Apache will also be blogged. I’ll definitely try and take some photos of the events.
New Guitar
My latest Guitar arrived today. It’s a tenor guitar (four string) tuned in 5ths. It’s all-solid, with rosewood back, sides and fretboard. That and the maple top on it give it a rich full tone, it really rings like a bell.
It arrived in the “standard” CGDA tuning, which I really don’t like, so straight on with some new nickel strings (I prefer the tone nickel-wound strings give, even when not using a magento pickup) and lowered by a fourth to give GDAE and it was sounding much better. Right now it’s tuned ADAD, and that’s proving useful also.
For anyone looking for tenor guitar gauges with Google, I used; .40w, .30w, .20w and .12, my scale length is 552mm. I’ll write a much better entry about the guitar, where I got it from, as well as some tenor guitar history in the next few days.
New York
Posted on July 12, 2005, under general, photography.
I havn’t blogged in a while, mainly because I’ve been in New York. Myself and Noirin kept a travelblog, which includes all of our photos as well. But here’s a sample of what kind of great shots the weather provided.
It was great fun! Had a brilliant time with Noirin, and took loads of good photos. Manhattan is excellent for that, point your lense almost anywhere and you have a good shot.