I'm trying to run a server on solar power. (I can buy a lot of solar panels for what PG&E would charge to run power lines.) So I'm trying to figure out how to minimize power. I tried using the hdparm -S to spin down the disk drive when idle. The problem is it never is!
First, the cpuspeed daemon writes out a log message May 12 10:37:34 kelso kernel: longhaul: FSB:133 Mult:5.5x multiple times a minute. This is due to a dprintk in /usr/src/linux-2.6.5-1.327/arch/i386/kernel/cpu/cpufreq/longhaul.c I can disable the cpuspeed service, but that doesn't seem like a good idea if I'm concerned about power usage! Can this message be removed?
Second, a bunch of things get run by cron. mailman wants cron to run gate_news every 5 minutes. This is still going on even after I disables mailman in the services configuration. I can presumably edit /var/mailman/cron/*, but I shouldn't have to if I've turned off the mailman service.
mrtg is also run every 5 minutes, and I have no idea how to turn that off.
/usr/lib/sa/sa1 is run every 10 minutes, and I'd like to turn that off or run it less frequently. (I assume this is "system accounting" but I'm not sure).
These are bad enough, but when I run iostat it tells me that something is writing to the disk every 5 or 10 seconds! If I can't fix this there is no way to ever spin down the disk.
How about putting enough memory into the system and load the whole the image into ram and only use HD for data storage?
There are ways of doing it but I don't know how. Look for diskless workstations.
-- Robin Laing