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User Journal

Journal Journal: Short bus 1

http://lwn.net/Articles/354860/

Sometimes you can really appreciate living in a world that isn't 100% driven by a company's bottom line. Can you imagine the uproar if Gates, Ballmer or Jobs had come out with a comment like that? Yaaay Linus.

Spam

Journal Journal: Holy crap, that's a lot of spam 2

Some while back, spam became a sufficiently large problem for me that I decided to do something about it. After looking around at the options, I decided to go with bogofilter. It's small, fast, and written in C. These are all good things. It looks at each message and builds up a database of words and the frequency with which they appear in spam and ham, and uses that to classify each incoming message. So far so good. It seems to work very well. When it's not sure, it says so, and files the message in an "unsure" folder, and asks me to manually classify those messages. It also uses that clarification to further learn the difference between ham and spam for future messages. This all sounds ideal.

The problem is that my main server was starting to spend a significant proportion of its time in disk wait state, while the bogofilter processes tried to access the word database. The load average hit 100 last night, which was an indication that things had gone badly wrong and I needed to do something about it. I don't know how Berkeley DB is implemented internally, but my guess would be that it's vague hash table shaped, and so the size of the database shouldn't significantly affect lookup times. But I don't know that for sure, and my database had grown to a non-trivial 1.5GB in size. Furthermore, bogoutil was failing to read the database file, possibly indicating that it was corrupt, which might have been causing each bogofilter pass to take much longer than necessary, and hence increase contention for the database file on disk.

So at this point, I decided to scrap the word database and start again. I have a corpus of both ham and spam that I used for the initial training, which I knew wouldn't be perfect, but it was a good start, and I could further train it up over time. Then I left it and went to bed. This morning, I realised just how much work bogofilter had been doing on my behalf. You see, in the 12 hours since I switched over to the new word database, I received 18,000 spam messages that bogofilter was now no longer filtering out for me. I knew the spam problem was bad, but that's at least an order of magnitude worse than I expected.

The next step is to train up bogofilter again so that it filters the majority of those out for me, and given the volume of mail that I'm getting, I think I'm going to need to use bogofilter to feed a Jef Poskanzer style dynamically updated block list that I can pass to blackmilter. 18,000 messages (plus however many bogofilter blocked) in 12 hours? That's insane.

User Journal

Journal Journal: Unicode woes

Bizarre, I posted this earlier today, yet it seems to have disappeared. Maybe I just didn't hit submit after the preview. Anyway:

<?xml version=\"1.0\" encoding=\"UTF-8\"?>

Grrr. If you're going to stick that at the top of your feed, please mean it. 0xA0 is Latin1, not UTF-8. Lying to me like that just makes my life miserable :-(

User Journal

Journal Journal: Fedora 11 2

I was looking forward to installing the recently released Fedora 11. But sadly, it was not to be. The installer fails. And by that, I mean it doesn't even get as far as the installer itself. I can't get beyond ISOLINUX. The "Press Enter to begin the installation" message appears to mean "Press Enter repeatedly and bugger all will happen". Sadly, I can't even report it as a bug. The Red Hat bugzilla has decided that my password has expired, but doesn't want to send me a password reset token :-(
User Journal

Journal Journal: If I had a time machine... 3

I'd go back, find whoever invented multithreading, and blow their brains out before they had a chance to do so. Great when it works, a pain in the arse to debug when it doesn't :-(
User Journal

Journal Journal: SQL isn't quite as braindead as I thought 2

Don't get me wrong, SQL is a hideous language that makes it hard to express common things, and impossible to express some more complex things. But today I learned about the coalesce() function, which makes it just that little bit more bearable.
User Journal

Journal Journal: Tiscali must die 2

Tiscali must die. And I'm not talking about a quick death, either. No, this needs to be long and painful, and I need to be there to gloat while they suffer.

A greater hive of ineptitude and incompetence you will not find anywhere in the galaxy. I've logged the fault, but if their track record is anything to go by, it'll disappear in to the ether, never to be seen again, and the problem (in this case, they're bouncing my email) will be resolved at some undetermined point far in the future :-(

Hardware Hacking

Journal Journal: I hate PC hardware 11

So it came to pass that I ran out of disk space in my server. No problem. Storage is cheap, so I went and bought myself a couple of 750GB disks, from two different manufacturers, to turn into a RAID1 mirror. So far, so good. On a whim, I shut down my desktop machine (which uses the server for NFS/NIS/DNS etc) before taking the server down. Once the disks were installed, the server came back up fine... but my desktop refused to boot :-(

The machine powered up, fans were whirring away, but all I got was a blank screen, not even getting as far as showing the BIOS POST information. No diagnostic beeps. Nothing. A bit of digging and judicious unplugging of everything in turn revealed it to be a bad memory stick. Of course, as is the way of PC hardware, not only does it fail frequently, but when it does, it's considered obsolete, so you can't easily replace it anyway. My local PC components shop no longer sells DDR400 RAM, so I'll have to get some mail order, which will no doubt take forever. In the mean time, I'm limping along with 512MB RAM. Sigh...

Music

Journal Journal: So that was 2008 5

A bit late, but who cares?

In the studio

  1. Mötley Crüe -- "Saints of Los Angeles"
  2. Blaze Bayley -- "The man who would not die"
  3. Hanging Doll -- "Reason and madness"
  4. Liquid Sky -- "Identity"
  5. Guns N' Roses -- "Chinese democracy"
  6. Judas Priest -- "Nostradamus
  7. Into The Woods -- "Into the woods"
  8. Battlelore -- "The last alliance"
  9. AC/DC -- "Black ice"
  10. Firewind -- "The premonition"

Not a great year, but not a bad one either, and a few surprises. I wasn't expecting Mötley Crüe to come out with such a strong album ever again. Nor was I expecting the GNR album to be any good. Indeed, I wasn't even planning on getting it at all, but it was cheap in the Woolworth's closing down sale. While it's not as good as they were 20 years ago, it's not bad. Of course, there's every reason to call the band Axl And The Hired Guns rather than GNR, but that's an argument for another day. Judas Priest had made a great return to form with their reunion album, so it was a bit of a disappointment to see them follow it up with "Nostradamus". There's nothing wrong with the album, but there's not much memorable about it either. In truth, only perhaps the top four albums in the list are really worthy of their place, and while I like the others, they're nothing special.

There are a few albums from 2008 that I haven't heard yet, but had I done so, I might reasonably expect them to make a showing in my list of favourite albums of the year:

  • Sabaton -- "The art of war"
  • Falconer -- "Among beggars and thieves"
  • Avantasia -- "The scarecrow"
  • Alice Cooper -- "Along came a spider"

On stage

For me, 2008 saw 151 bands playing at 34 shows. The highlights were:

  1. Rage, The Underworld
  2. Sabaton, The Purple Turtle
  3. Pain, The Astoria
  4. Heaven's Basement, Bloodstock Open Air
  5. Blaze Bayley, The Underworld
  6. Dio, The Astoria
  7. Hanging Doll, The Underworld
  8. Liquid Sky, The Peel
  9. Metalloid, Bloodstock Open Air
  10. Scorpions, Hammersmith Apollo
  11. Hellfighter, Bloodstock Open Air
  12. Liquid Sky, Barfly
  13. Mantra, Bloodstock Open Air
  14. Ensiferum, Paganfest, Koko

Another strong year in terms of live performances. I hadn't been impressed with Rage's "Speak of the dead" album, so despite some good performances in the past, my expectations weren't high. Fortunately, they were touring in support of a vastly better new album, "Carved in stone", and on the strength of their excellent performance at The Underworld, I picked up that album at the show. A great choice of setlist, and they even brought out Jen Majura for a few songs, including "Dies Irae", a song I never thought I'd hear them play live.

Sabaton blew me away the first time I saw them, and since then I've been to all of their London shows. Once again, they were outstanding. Pain were something of a surprise. I'd been vaguely aware of their earlier material, but it hadn't really made an impression. But what a live band! They completely blew headliners Nightwish off the stage. Other notables this year were the large number of good performances at Bloodstock, particularly from bands I'd never heard of before (Metalloid, Hellfighter and Mantra stand out there).

Also of note was Liquid Sky's change of vocalist. I thought they'd struggle to replace Hecate, who put in a great performance at Barfly early in the year. Her replacement, Tiffeny, looked competent at Bloodstock, but a bit shaky. Then again, it was her first ever show with the band, and when I saw them again at The Peel later in the year, they were much improved. It was the last date of their tour, and it showed. Having had a bit of practice, she was much more at ease, and far more confident on stage, which made for a great show.

On the screen

This is where I struggle a bit. I didn't see many films this year. Indeed, off the top of my head, I can only recall two. The first was "The dark knight", which was hugely overrated. A decent performance from Ledger, but a poor film overall, and very disappointing after the promise shown by "Batman begins". The second was "Burn after reading". Holy crap. I want those two hours of my life back. How can such an all star cast end up producing such a terrible film?

Since we don't have TV reception, I can't comment on anything there. However, we've been watching a bunch of stuff on DVD. "Heroes" was excellent, and I can't wait to see the second season. I bought the complete set of "The X-Files", which is nearly a week of continuous 24x7 viewing. We've done the first series so far. Also seeing time on the DVD player have been "Magnum", "Dexter", "Doctor Who" and "Torchwood", all of which were good.

Operating Systems

Journal Journal: OpenBSD fail :-( 3

Bah. The hard drive on my firewall failed last night. I reinstalled onto a new drive this morning, but I can't get NATing to work :-( Packets are coming in on the internal interface, and leaving fine on the external interface, but aren't being NATed on the way through. I'm using a simplified pf.conf which looks like:

int = "fxp0"
ext = "rl0"

nat on rl0 from 192.168.8.4 to any -> 10.0.8.230

block in log
pass in log quick on $int
pass out log on $ext keep state

But packets are still leaving rl0 with a source IP of 192.168.8.4. Does anyone have any ideas about where I might be going wrong? Jorg?

Emulation (Games)

Journal Journal: Crap 5

1. 35118 Tet the High-Elf Mage, Level 25
Killed by Shagrat, the Orc Captain on dungeon level 15 (Max 16)
(User 500, Date 2008-11-22, Gold 3659, Turn 3036336).

:-(

The Internet

Journal Journal: Livejournal downtime 3

From a recent LJ news item: Our San Francisco data center is taking a little downtime for power maintenance, which means so are we

Errr... why? For a site as busy as LJ to be based solely in one data centre seems to be bordering on negligence to me. Sure, there are some issues with having multiple data centres, particularly if you're running them in active-active mode (I know, I've done it). But to not at least have an active-passive setup with a standby data centre? I don't get it. Why would you want to put all your eggs in one basket like that?

Also... Outage from power maintenance? In a datacentre? That's why they have redundant power, so you don't have to have an outage when they need to do stuff like that. I'd be horrified if my data centre did that to me.

User Journal

Journal Journal: The magic smoke escaped 3

I was at the race track over the weekend. During that time, my file server died. The symptoms indicated a faulty power supply. Fortunately, I keep a spare around for just such occasions. I swapped the new power supply in this morning (new as in brand new, still shrink wrapped), and powered it on. I wasn't expecting to be greeted by a loud bang, a flash of blue flame and a shower of sparks. I mean, I've had power supplies nominally "explode" before, but this is the first time I've actually had a real, physical explosion. I just hope it didn't fry the motherboard in the process. I'll find out when I get home this evening...
Mozilla

Journal Journal: Firefox memory usage 8

I make no secret of the fact that I think Firefox is a poor excuse for a browser. It just happens to be the best of the bad bunch that is currently available. Apparently, great strides have been made in terms of memory usage with firefox 3. And to give them credit, that does seem to be mostly true. It does appear less memory hungry than earlier versions. But I still had to kill it off this afternoon, when the firefox process had grown to 2.4GB. That was a bit of a problem on a machine with 2GB of physical RAM. Swapping never makes for a pleasant desktop experience...
User Journal

Journal Journal: rlwrap and the benefits of an open plan office

So we were sitting around at work yesterday, and one of my orkers of bovines asked if anyone could remember the name of the utility that allowed a non-readline enabled application to use readline. I'd never heard of such a thing, but one of the other developers piped up: rlwrap. Wow. What an amazingly useful little app. There's something to be said for working in the same office as the rest of your team. What you lose out in terms of privacy and quiet coding time, you more than make up in terms of information exchange.

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