Hi, On Tue, Jan 01, 2008 at 02:45:13PM +0100, Peter Ganzhorn wrote: > Hi, > > I've tried to save some power with my laptop by powering down my disk > via "hdparm -y /dev/sda". The disk stops spinning immediately but will > start up within 5 seconds or less. > To find out what's keeping the disk busy I got me blktrace and blkparse > and it seems the following processes keep the disk busy all the time: > > swapper > pdflush > xfssyncd > xfsbufd > > Is there any way to suspend those processes if I want to power down my disk?
You probably need to enable linux/Documentation/laptop-mode.txt (but in this case watch those hdparm -B settings!!! 600000 head unloads may already kill a drive, judging from mfct. specifications!), also you perhaps need to adjust the dirty flush setting as suggested by powertop (suggested to increase from 5 to 15 seconds, dunno what the setting was called exactly). And I wouldn't do this unless one achieves notebook HDD powerdown lengths above 2 minutes at least, otherwise I'd be concerned about HDD health. (better watch those smartctl SMART usage count increments!) Andreas Mohr _______________________________________________ Power mailing list [email protected] http://www.bughost.org/mailman/listinfo/power
