Update help text for powersave hooks that display help.

6 files changed, 59 insertions, 34 deletions

diff --git a/pm/power.d/harddrive b/pm/power.d/harddrive
index 4bad394..a454170 100644
--- a/pm/power.d/harddrive
+++ b/pm/power.d/harddrive
@@ -19,30 +19,27 @@ DRIVE_LIST="/dev/[hs]d[a-z]"
 
 help() {
 cat <<EOF
-Hard drive Parameters we support tweaking:
+--------
+$0: Control hard drive spindown, write caching, 
+    power management and acoustic management.
 
-Drive spindown:
+This hook has 8 tuneable parameters:
 DRIVE_SPINDOWN_VALUE_AC = time until a drive will spin down on AC
 Defaults to 0, which disables drive spindown.
-
 DRIVE_SPINDOWN_VALUE_BAT = time until a drive will spin down on battery
 Defaults to 6, which will spin the drive down after 30 seconds of inactivity.
 
-See the -S option on the hdparm manpage.
-
-Drive write caching:
-DRIVE_WRITE_CACHE_AC  = 0 disables write cache, 1 enables it.
-Defaults to 1
+See the -S option on the hdparm manpage for more information.
 
-DRIVE_WRITE_CACHE_BAT  = 0 disables write cache, 1 enables it.
-Defaults to 0
+DRIVE_WRITE_CACHE_AC = Whether the drive caches writes on AC
+Defaults to 1, which means that the drive will cache writes internally.
+DRIVE_WRITE_CACHE_BAT = Whether the drive caches writes on battery.
+Defaults to 0 which means that the drive will not cache writes internally.
 
-See the -W option on the hdparm man page.
+See the -W option on the hdparm man page for more information.
 
-Drive power management:
 DRIVE_POWER_MGMT_AC = Drive Advanced Power Management value on AC
 Defaults to 254 for max performance.
-
 DRIVE_POWER_MGMT_BAT = Drive Advanced Power Management value on battery
 Defaults to 1 for max power savings.
 
@@ -51,7 +48,6 @@ See the -B option on the hdparm man page
 Drive acoustic management:
 DRIVE_ACOUSTIC_MGMT_AC = Drive Acoustic Management value on AC
 Defaults to 254 for max head speed.
-
 DRIVE_ACOUSTIC_MGMT_BAT = Drive Acoustic Management value on battery
 Defaults to 128 for max quietness.
 
diff --git a/pm/power.d/intel-audio-powersave b/pm/power.d/intel-audio-powersave
index aa86950..2bf0a51 100644
--- a/pm/power.d/intel-audio-powersave
+++ b/pm/power.d/intel-audio-powersave
@@ -8,7 +8,10 @@ INTEL_AUDIO_POWERSAVE=${INTEL_AUDIO_POWERSAVE:-true}
 
 help() {
 cat <<EOF
-Intel Audio powersave parameters:
+--------
+$0: Intel Audio powersave parameters.
+
+This hook has 1 tuneable parameter. 
 INTEL_AUDIO_POWERSAVE = controls whether we will try to save power on battery.
 Defaults to true.
 
diff --git a/pm/power.d/laptop-mode b/pm/power.d/laptop-mode
index 844ac85..5f873db 100644
--- a/pm/power.d/laptop-mode
+++ b/pm/power.d/laptop-mode
@@ -13,22 +13,36 @@ LAPTOP_DIRTY_WRITEBACK=${LAPTOP_DIRTY_WRITEBACK:-60000}
 
 help() {
     cat <<EOF
-Laptop mode VM tuning parameters:
+--------
+$0: Laptop mode tuning parameters.
+This hook controls how agressive the system is at trying to avoid
+writing to disk.  The longer the disk is idle, the more power you can save.
 
+This hook is only active on battery power, and it restores these values
+to kernel defaults when on AC power.
+
+It has 4 tuneable parameters: 
 LAPTOP_MODE = value for laptop_mode on battery.
-Defaults to 1, which enables laptop mode.
+Defaults to 5, which enables laptop mode and forces the system to wait 
+5 seconds whenever something asks to write to disk to flush out as much
+data as we can.
 
 LAPTOP_DIRTY_RATIO = the ratio of dirty memory to all memory that 
-processes start doing their own writeout.  Defaults to 60.
+processes start doing their own writeout.  
+Defaults to 60, which means that the kernel will not start forcing process
+to write out file information that has been changed but not saved until 60%
+of usable system memory is filled with dirty information.
 
 LAPTOP_DIRTY_BG_RATIO = The ratio of dirty memory to all memory that 
-pdflush will wake up and start writing to disk.  Defaults to 40.
+pdflush will wake up and start writing to disk.  
+Defaults to 40, which means that the kernel will wake up a helper process
+to try and write out dirty memory once 40% of usable system memory is dirty.
 
 LAPTOP_DIRTY_WRITEBACK = The number of centiseconds between periodic
-wakeups of the pdflush daemons.  Defaults to 60000 (10 minutes).
+wakeups of the pdflush daemons.  
+Defaults to 60000 (10 minutes), which menas that the kernel will flush dirty
+memory every 10 minutes if dirty memory never hits 40% of system memory.
 
-These only take place on battery.  This hook will revert to the kernel
-default values on AC power.
 
 EOF
 }
diff --git a/pm/power.d/readahead b/pm/power.d/readahead
index 006034b..2009c84 100644
--- a/pm/power.d/readahead
+++ b/pm/power.d/readahead
@@ -10,18 +10,19 @@ DRIVE_READAHEAD_BAT=${DRIVE_READAHEAD_BAT:-3072}
 
 help() {
     cat <<EOF
-Drive readahead parameters:
+--------
+$0: Control drive readahead.
+
+This hook tries to trade off the number of times we spin up a drive
+to read for potentially wasted cache.
 
+Drive readahead parameters:
 DRIVE_READAHEAD_AC = Number of KB to speculatively read on AC.
 Defaults to 256 KB.
 
 DRIVE_READAHEAD_BAT = Number of KB to speculatively read on battery.
 Defaults to 3072 KB.
 
-The theory here is that we trade off the number of times we spin up a drive
-to read for potentially wasted cache if we end up not needing all the data we
-read.
-
 EOF
 }
 
diff --git a/pm/power.d/sata_alpm b/pm/power.d/sata_alpm
index e102998..82c8201 100644
--- a/pm/power.d/sata_alpm
+++ b/pm/power.d/sata_alpm
@@ -6,8 +6,15 @@ SATA_ALPM_ENABLE=${SATA_ALPM_ENABLE:-true}
 
 help() {
 cat <<EOF
-SATA link ALPM parameters:
+$0: SATA link power management
 
+This hook tries to save power by allowing SATA controllers to
+reduce power usage when the SATA subsystem is otherwise idle.
+
+This adds a little bit of latency to drive accesses in
+exchange for moderate power savings if you are not using the drive.
+
+This hook has 1 parameter:
 SATA_ALPM_ENABLE = whether to use SATA ALPM on battery.
 Defaults to "true".
 
diff --git a/pm/power.d/xfs_buffer b/pm/power.d/xfs_buffer
index ebf3384..d21e845 100644
--- a/pm/power.d/xfs_buffer
+++ b/pm/power.d/xfs_buffer
@@ -10,19 +10,23 @@ XFS_SYNCD=${XFS_SYNCD:-60000}
 
 help() {
     cat <<EOF
-XFS filesystem powersaving parameters:
+--------
+$0: XFS filesystem buffer control hook.
 
+This hook tries to save power by tuning any XFS filesystems to delay writing
+dirty metadata.  It only takes effect on battery, when the system switches
+to AC power it will restore the kernel defaults.
+
+This hook has 3 parameters:
 XFS_AGE_BUFFER = How old an XFS filesystem buffer can be before it is flushed.
-Battery value defaults to 60000, or 10 minutes (600 seconds)
+Defaults to 60000, or 10 minutes (600 seconds)
 
 XFS_BUFD = How often XFS will scan for dirty metadata to flush it.
-Battery value defaults to 3000, or 30 seconds.
+Defaults to 3000, or 30 seconds.
 
 XFS_SYNCD = How often an XFS filesystem will perform other filesystem 
-maintenance, Battery value defaults to 60000, or 10 minutes.
+Defaults to 60000, or 10 minutes.
 
-These values only affect powersave on battery, on AC power the system will use
-its defaults.
 EOF
 }