From: Bart Samwel The laptop mode control script incorrectly guesses XFS_HZ=1000. This is incorrect, since the patches that made XFS use USER_HZ went into 2.6.6 as well. This changes XFS_HZ to 100 and removes the warning from the doc about checking XFS_HZ. --- 25-akpm/Documentation/laptop-mode.txt | 18 +++++++----------- 1 files changed, 7 insertions(+), 11 deletions(-) diff -puN Documentation/laptop-mode.txt~update-laptop-mode-control-script-with-xfs_hz=100 Documentation/laptop-mode.txt --- 25/Documentation/laptop-mode.txt~update-laptop-mode-control-script-with-xfs_hz=100 Tue May 11 15:36:57 2004 +++ 25-akpm/Documentation/laptop-mode.txt Tue May 11 15:36:57 2004 @@ -69,13 +69,6 @@ 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 @@ -328,10 +321,13 @@ DEF_DIRTY_RATIO=40 DEF_XFS_AGE_BUFFER=15 DEF_XFS_SYNC_INTERVAL=30 -# 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." _