#!/bin/sh --
# This value must be identical to the commit inverval for the filesystem
FLUSH_INTERVAL=120000  # 20 minutes (measured in 0.01 seconds)

DIRTY_RATIO=40        # (percent)


AC_POWER=$(grep -c on-line /proc/acpi/ac_adapter/ADP1/state)
SPINDOWN=$(cat /proc/sys/vm/laptop_mode)

echo ac event power is $AC_POWER spindown was $SPINDOWN >/dev/tty8

if [ $AC_POWER = 0 ]
then
  if [ $SPINDOWN = 0 ]
  then
    # spindown after 20 seconds
    /sbin/hdparm -S 4 /dev/hda

    echo 1                    > /proc/sys/vm/laptop_mode
    echo "$FLUSH_INTERVAL"    > /proc/sys/vm/dirty_writeback_centisecs
    echo "$FLUSH_INTERVAL"    > /proc/sys/vm/dirty_expire_centisecs
    echo "$DIRTY_RATIO"       > /proc/sys/vm/dirty_ratio
    echo "$DIRTY_RATIO"       > /proc/sys/vm/dirty_background_ratio
  fi
else
  if [ $SPINDOWN != 0 ]
  then
    # spinup
    /sbin/hdparm -S 0 /dev/hda

    # reset kernel defaults
    echo 0                    > /proc/sys/vm/laptop_mode
    echo 500                  > /proc/sys/vm/dirty_writeback_centisecs
    echo 3000                 > /proc/sys/vm/dirty_expire_centisecs
    echo 40                   > /proc/sys/vm/dirty_ratio
    echo 10                   > /proc/sys/vm/dirty_background_ratio
  fi
fi