On Tue, 1 Jan 2008 16:32:48 +0100 Andreas Mohr <[EMAIL PROTECTED]> wrote:
> 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 You may want to check the laptop-mode tools website: http://samwel.tk/laptop_mode/ And for the dirty ratios and stuff I found the following quite informative: http://www.westnet.com/~gsmith/content/linux-pdflush.htm Having said this, I haven't managed to get the behaviour I want for my laptop. Closest was once I played with the parameters mentioned in the second link, but I hadn't made them permanent so I suffer from almost permanent HD activity (well, spinning, not accessing). Which is kind of annoying for sometimes I can be for long periods of time just surfing the web and the drive could be perfectly quiet... _______________________________________________ Power mailing list [email protected] http://www.bughost.org/mailman/listinfo/power
