Journal entries for March, 2008

Over the past year or so I've noticed BinRock getting slower and slower. It got so bad that visitors' web browsers were timing out before BinRock got around to sending them the page they were waiting for. I don't get any notification when a visitor times out, but for the last few months, I've been getting 5-10 error messages a day from my own scripts that load BinRock pages for one reason or another, and I can extrapolate from that and guess that it's been quite a lot.

In Linux, there's a measure of how heavily the machine is loaded, aptly called the "load average." A value between 0.0 and 1.0 means that the machine is only partially being used, and it's spending part of its time idle. A value of 1.0 effectively means that there is something using the CPU at all times, but nothing is being made to wait. That's just about perfect — you're not wasting hardware sitting around doing nothing, but you're also not overloading it. Values above 1.0 mean that the machine is overloaded, and processes are having to sit around waiting for their turn to run. Generally, if you see it reach 2.0 or more, the machine will be running pretty slowly and it'll be really obvious to the users.

For years, BinRock's load average was down around 0.10 — it wasn't even breaking a sweat serving all the web sites, email accounts, etc that are hosted there. But for the last year, the load has started growing steadily, and during the last few months, I'd regularly see it get as high as an astounding 30.0. Hence all the timeouts.

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It's convenient how every year at midnight on March 14 I get a handy reminder of exactly which vBulletin-powered message boards I'm still registered in. It's a walk down memory lane, because many of them I haven't visited in months or years. It's touching that they haven't forgotten me despite my neglectful inattention.

I think SupraForums is really really glad it's my birthday.

I've always been really interested in robotics and artificial intelligence, but because I changed majors in Freshman year from computer engineering to computer science, I missed out on the chance to get any real formal education in the field. I did take one electrical engineering class where we learned to breadboard circuits and stuff, and it was actually one of my favorite classes at Clemson. But it was only an introduction to the subject and didn't really get into detail, and so despite my longstanding interest in the field, I've never really known how to go about making the jump and actually start doing it.

I have a Lego Mindstorms kit that I've toyed with, but the inherent fragility of Legos was always a limitation. I found that if I tried to fashon an arm to pick stuff up with, I couldn't apply too much force or it'd just smash itself to pieces spectacularly. So the desire to learn to build "real" robots out of metal has stuck with me.

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