Beat my uptime: 3 years!

By Andrew Smith

andrew@littlesvr:~$ uptime
13:26:34 up 1104 days, 10:14,  4 users,  load average: 0.61, 0.31, 0.21

I guess 1100 days doesn’t sound like a lot but 3 years does :)

It’s still the same machine I mentioned a year ago. It’s been running and running and running, and not crashing!

Theoretically 3 years is not a lot, but in the real world such uptime requires a combination of luck, great software, and good hardware. A power failure will kill it. A kernel update will kill it. A kernel that can’t handle the load will kill it. An admin who doesn’t know how to upgrade or restart services without a reboot will kill it. A bad fan will kill it. And mine is still up :)

Even cdot, which is running Slackware 9 (littlesvr is running 12.2) has only been up for 208 days today though I’m guessing it’s sitting in a real server room and has real admins taking care of it.

Yesterday (this was after the 3 year mark) I thought my server was finally about to die. When I realised what was going on there were 115 httpd processes running, I had 25MB of physical memory and 36MB of swap space left. Sendmail fell over, refusing to work with a load average over 15 (it got to 44). Sshd stopped accepting connections. imapd could barely serve requests. Interestingly Apache still worked.

I tailed the apache logs (this took me a half an hour, working entirely off swap is very slow) and saw nothing unusual. I have no idea what got into it, why the suicidal behaviour. In the logs there were only the typical 2-3 requests and 2-3 errors per minute. I tried to run apachectl status but that was taking too long. So I did the obvious, apachectl stop. After 5-10 minutes the harddrive light stopped blinking, and littlesvr breathed a sigh of relief.

As for me – I’m not really sure that I cared if it died. 3 years is a lot, I’m starting to get itchy to upgrade software (though it works perfectly fine) and to upgrade the hardware (512MB of RAM is too little). Even during normal operations I’m using almost all my RAM, and hopefully the load will be heavier in the future.

Maybe when the next Slackware comes out I’ll decide whether today’s 13.37 is a stable enough version for the long term.