Re: which process is accessing my hard drive?

[Mika Fischer <mika_fischer@gmx.net>]

Matt Price wrote:
> Anyone know how to tweak kupdated or the "dirty buffer" "flushing"
> time using sysctl?  Unfortuantely I don't even really knwo what these
> phrases mean
> (I can sorta guess)...   I tried "sysctl -a" but the output wasn't
> particularly meaningful to me, and grep -i update produced no output.
> Anyone have ideas here?

Take a look at the laptop-mode script.

What it does is basically this:

MAX_AGE=600            # 10 minutes in seconds
DIRTY_RATIO=40         # percentage of dirty pages allowed
AGE=$((100*$MAX_AGE))  # I actually don't know what unit this is ;)
                       # but it sould also be 10 minutes
mount -oremount,commit=$MAX_AGE  # for all journaling filesystems
case "$KLEVEL" in
"2.4")
     echo "1" > /proc/sys/vm/laptop_mode
     echo "30 500 0 0 $AGE $AGE 60 20 0" > /proc/sys/vm/bdflush
     ;;
"2.6")
     echo "1" > /proc/sys/vm/laptop_mode
     echo "$AGE" > /proc/sys/vm/dirty_writeback_centisecs
     echo "$AGE" > /proc/sys/vm/dirty_expire_centisecs
     echo "$DIRTY_RATIO" > /proc/sys/vm/dirty_ratio
     echo "$DIRTY_RATIO" > /proc/sys/vm/dirty_background_ratio
     ;;
esac

in /etc/sysctl.conf this should look something like this (for 2.4.x):
vm/laptop_mode = 1
vm/bdflush = 30 500 0 0 60000 60000 60 20 0

HTH,
 Mika