On Sun, Aug 17, 2003 at 02:50:01PM +0200, Kristian Peters wrote: > Hello. > > Compared to OSX my iBook 900MHz is getting really hot. I'm using > 2.4.21-ben2 currently, but a vanilla kernel is even worse. > According to /proc/cpuinfo temperature is in normal range. There > is no big difference if I descale cpu frequency to 400 MHz. > Battery will only last for 3,0 hours then (instead of 3,3 under > OSX). Even cpufreqd can't help lowering temperature.. > > Any other suggestions ?
Lowering the TFT brightness will help a lot. Another thing you should check is hard disk work. If you're using some journal-enabled fs (eg: ext3), you should notice that your disk _never_ stops, because of the constant syncing of metadata. IIRC, -benh kernels have some control over this, but I have not my laptop nearby and on to check. I have ext3 and I think I configured it (mount options, at /etc/fstab) to sync every 60 seconds, or so, instead of every 5 seconds. Of course, you're having a lot more risk of data loss, but that's no problem for me, as my first concern on my laptop is battery time. You can check the laptop-mode patch too. It does some nifty (and dangerous) things as stoping your disk and deferring most data writes to a single point, when it starts the disk, writes, and stops it again. With those tricks, and using cpudynd to dynamically change between 400 & 800MHz, I usually get +4 hours of battery time.
