patch-2_6_7-vs1_9_1_12

[linux-2.6.git] / Documentation / laptop-mode.txt

diff --git a/Documentation/laptop-mode.txt b/Documentation/laptop-mode.txt
index 9df8d26..423ecef 100644 (file)
--- a/Documentation/laptop-mode.txt
+++ b/Documentation/laptop-mode.txt
@@ -69,12 +69,10 @@ Caveats
 * If you have your filesystems listed as type "auto" in fstab, like I did, then
   the control script will not recognize them as filesystems that need remounting.
 
-* If you have XFS, make SURE that you set the XFS_HZ value in the control script
-  correctly, to the value of HZ of your running kernel. Laptop mode will not
-  work correctly if it is set too low, and you may lose data if it is set too
-  high. The reason for this problem is that XFS does not export its sysctl
-  variables in centisecs (like most other subsystems do) but in "jiffies",
-  which is an internal kernel measure. Once this is fixed things will get better.
+* It has been reported that some versions of the mutt mail client use file access
+  times to determine whether a folder contains new mail. If you use mutt and
+  experience this, you must disable the noatime remounting in the control script
+  by setting DO_REMOUNT_NOATIME=0.
 
 
 The details
@@ -281,7 +279,13 @@ parse_mount_opts_wfstab () {
        fi
 }
 
-KLEVEL="$(uname -r | cut -c1-3)"
+KLEVEL=$(
+           uname -r |
+             (
+              IFS="." read a b c
+              echo $a.$b
+            )
+        )
 case "$KLEVEL" in
        "2.4"|"2.6")
                true
@@ -295,6 +299,9 @@ esac
 # Shall we remount journaled fs. with appropiate commit interval? (1=yes)
 DO_REMOUNTS=1
 
+# And shall we add the "noatime" option to that as well? (1=yes)
+DO_REMOUNT_NOATIME=1
+
 # age time, in seconds. should be put into a sysconfig file
 MAX_AGE=600
 
@@ -319,11 +326,15 @@ DEF_DIRTY_BACKGROUND_RATIO=10
 DEF_DIRTY_RATIO=40
 DEF_XFS_AGE_BUFFER=15
 DEF_XFS_SYNC_INTERVAL=30
+DEF_XFS_BUFD_INTERVAL=1
 
-# This must be adjusted manually to the value of HZ in the running kernel,
-# until the XFS people change their external interfaces to work in centisecs
-# like the rest of the external world. Unfortunately this cannot be automated. :(
-XFS_HZ=1000
+# This must be adjusted manually to the value of HZ in the running kernel
+# on 2.4, until the XFS people change their 2.4 external interfaces to work in
+# centisecs. This can be automated, but it's a work in progress that still needs
+# some fixes. On 2.6 kernels, XFS uses USER_HZ instead of HZ for external
+# interfaces, and that is currently always set to 100. So you don't need to
+# change this on 2.6.
+XFS_HZ=100
 
 if [ ! -e /proc/sys/vm/laptop_mode ]; then
        echo "Kernel is not patched with laptop_mode patch."
@@ -335,6 +346,10 @@ if [ ! -w /proc/sys/vm/laptop_mode ]; then
        exit 1
 fi
 
+if [ $DO_REMOUNT_NOATIME -eq 1 ]; then
+       NOATIME_OPT=",noatime"
+fi
+
 case "$1" in
        start)
                AGE=$((100*$MAX_AGE))
@@ -342,19 +357,29 @@ case "$1" in
                echo -n "Starting laptop_mode"
 
                if [ -d /proc/sys/vm/pagebuf ] ; then
+                       # (For 2.4 and early 2.6.)
                        # This only needs to be set, not reset -- it is only used when
                        # laptop mode is enabled.
                        echo $XFS_AGE > /proc/sys/vm/pagebuf/lm_flush_age
                        echo $XFS_AGE > /proc/sys/fs/xfs/lm_sync_interval
                elif [ -f /proc/sys/fs/xfs/lm_age_buffer ] ; then
+                       # (A couple of early 2.6 laptop mode patches had these.)
                        # The same goes for these.
                        echo $XFS_AGE > /proc/sys/fs/xfs/lm_age_buffer
                        echo $XFS_AGE > /proc/sys/fs/xfs/lm_sync_interval
                elif [ -f /proc/sys/fs/xfs/age_buffer ] ; then
+                       # (2.6.6)
                        # But not for these -- they are also used in normal
                        # operation.
                        echo $XFS_AGE > /proc/sys/fs/xfs/age_buffer
                        echo $XFS_AGE > /proc/sys/fs/xfs/sync_interval
+               elif [ -f /proc/sys/fs/xfs/age_buffer_centisecs ] ; then
+                       # (2.6.7 upwards)
+                       # And not for these either. These are in centisecs,
+                       # not USER_HZ, so we have to use $AGE, not $XFS_AGE.
+                       echo $AGE > /proc/sys/fs/xfs/age_buffer_centisecs
+                       echo $AGE > /proc/sys/fs/xfs/xfssyncd_centisecs
+                       echo 3000 > /proc/sys/fs/xfs/xfsbufd_centisecs
                fi
 
                case "$KLEVEL" in
@@ -376,10 +401,10 @@ case "$1" in
                                case "$FST" in
                                        "ext3"|"reiserfs")
                                                PARSEDOPTS="$(parse_mount_opts commit "$OPTS")"
-                                               mount $DEV -t $FST $MP -o remount,$PARSEDOPTS,commit=$MAX_AGE,noatime
+                                               mount $DEV -t $FST $MP -o remount,$PARSEDOPTS,commit=$MAX_AGE$NOATIME_OPT
                                                ;;
                                        "xfs")
-                                               mount $DEV -t $FST $MP -o remount,$OPTS,noatime
+                                               mount $DEV -t $FST $MP -o remount,$OPTS$NOATIME_OPT
                                                ;;
                                esac
                                if [ -b $DEV ] ; then
@@ -395,9 +420,14 @@ case "$1" in
                echo -n "Stopping laptop_mode"
                echo "0" > /proc/sys/vm/laptop_mode
                if [ -f /proc/sys/fs/xfs/age_buffer ] && [ ! -f /proc/sys/fs/xfs/lm_age_buffer ] ; then
-                       # These need to be restored though, if there are no lm_*.
+                       # These need to be restored, if there are no lm_*.
                        echo "$(($XFS_HZ*$DEF_XFS_AGE_BUFFER))"         > /proc/sys/fs/xfs/age_buffer
                        echo "$(($XFS_HZ*$DEF_XFS_SYNC_INTERVAL))"      > /proc/sys/fs/xfs/sync_interval
+               elif [ -f /proc/sys/fs/xfs/age_buffer_centisecs ] ; then
+                       # These need to be restored as well.
+                       echo "$((100*$DEF_XFS_AGE_BUFFER))" > /proc/sys/fs/xfs/age_buffer_centisecs
+                       echo "$((100*$DEF_XFS_SYNC_INTERVAL))" > /proc/sys/fs/xfs/xfssyncd_centisecs
+                       echo "$((100*$DEF_XFS_BUFD_INTERVAL))" > /proc/sys/fs/xfs/xfsbufd_centisecs
                fi
                case "$KLEVEL" in
                        "2.4")
@@ -472,16 +502,16 @@ status=`awk '/^state: / { print $2 }' /proc/acpi/ac_adapter/AC/state`
 
 case $status in
         "on-line")
-                echo "Setting HD spindown to 2 hours"
-                /sbin/laptop-mode stop
+                echo "Setting HD spindown for AC mode."
+                /sbin/laptop_mode stop
                 /sbin/hdparm -S $ACAD_HD /dev/hda > /dev/null 2>&1
                 /sbin/hdparm -B 255 /dev/hda > /dev/null 2>&1
                 #echo -n $ACAD_CPU:$ACAD_THR > /proc/acpi/processor/CPU0/limit
                 exit 0
         ;;
         "off-line")
-                echo "Setting HD spindown to 20 seconds"
-                /sbin/laptop-mode start
+                echo "Setting HD spindown for battery mode."
+                /sbin/laptop_mode start
                 /sbin/hdparm -S $BATT_HD /dev/hda > /dev/null 2>&1
                 /sbin/hdparm -B 1 /dev/hda > /dev/null 2>&1
                 #echo -n $BATT_CPU:$BATT_THR > /proc/acpi/processor/CPU0/limit