1How to conserve battery power using laptop-mode 2----------------------------------------------- 3 4Document Author: Bart Samwel (bart@samwel.tk) 5Date created: January 2, 2004 6Last modified: December 06, 2004 7 8Introduction 9------------ 10 11Laptop mode is used to minimize the time that the hard disk needs to be spun up, 12to conserve battery power on laptops. It has been reported to cause significant 13power savings. 14 15Contents 16-------- 17 18* Introduction 19* Installation 20* Caveats 21* The Details 22* Tips & Tricks 23* Control script 24* ACPI integration 25* Monitoring tool 26 27 28Installation 29------------ 30 31To use laptop mode, you don't need to set any kernel configuration options 32or anything. Simply install all the files included in this document, and 33laptop mode will automatically be started when you're on battery. For 34your convenience, a tarball containing an installer can be downloaded at: 35 36http://www.samwel.tk/laptop_mode/laptop_mode/ 37 38To configure laptop mode, you need to edit the configuration file, which is 39located in /etc/default/laptop-mode on Debian-based systems, or in 40/etc/sysconfig/laptop-mode on other systems. 41 42Unfortunately, automatic enabling of laptop mode does not work for 43laptops that don't have ACPI. On those laptops, you need to start laptop 44mode manually. To start laptop mode, run "laptop_mode start", and to 45stop it, run "laptop_mode stop". (Note: The laptop mode tools package now 46has experimental support for APM, you might want to try that first.) 47 48 49Caveats 50------- 51 52* The downside of laptop mode is that you have a chance of losing up to 10 53 minutes of work. If you cannot afford this, don't use it! The supplied ACPI 54 scripts automatically turn off laptop mode when the battery almost runs out, 55 so that you won't lose any data at the end of your battery life. 56 57* Most desktop hard drives have a very limited lifetime measured in spindown 58 cycles, typically about 50.000 times (it's usually listed on the spec sheet). 59 Check your drive's rating, and don't wear down your drive's lifetime if you 60 don't need to. 61 62* If you mount some of your ext3/reiserfs filesystems with the -n option, then 63 the control script will not be able to remount them correctly. You must set 64 DO_REMOUNTS=0 in the control script, otherwise it will remount them with the 65 wrong options -- or it will fail because it cannot write to /etc/mtab. 66 67* If you have your filesystems listed as type "auto" in fstab, like I did, then 68 the control script will not recognize them as filesystems that need remounting. 69 You must list the filesystems with their true type instead. 70 71* It has been reported that some versions of the mutt mail client use file access 72 times to determine whether a folder contains new mail. If you use mutt and 73 experience this, you must disable the noatime remounting by setting the option 74 DO_REMOUNT_NOATIME to 0 in the configuration file. 75 76 77The Details 78----------- 79 80Laptop mode is controlled by the knob /proc/sys/vm/laptop_mode. This knob is 81present for all kernels that have the laptop mode patch, regardless of any 82configuration options. When the knob is set, any physical disk I/O (that might 83have caused the hard disk to spin up) causes Linux to flush all dirty blocks. The 84result of this is that after a disk has spun down, it will not be spun up 85anymore to write dirty blocks, because those blocks had already been written 86immediately after the most recent read operation. The value of the laptop_mode 87knob determines the time between the occurrence of disk I/O and when the flush 88is triggered. A sensible value for the knob is 5 seconds. Setting the knob to 890 disables laptop mode. 90 91To increase the effectiveness of the laptop_mode strategy, the laptop_mode 92control script increases dirty_expire_centisecs and dirty_writeback_centisecs in 93/proc/sys/vm to about 10 minutes (by default), which means that pages that are 94dirtied are not forced to be written to disk as often. The control script also 95changes the dirty background ratio, so that background writeback of dirty pages 96is not done anymore. Combined with a higher commit value (also 10 minutes) for 97ext3 or ReiserFS filesystems (also done automatically by the control script), 98this results in concentration of disk activity in a small time interval which 99occurs only once every 10 minutes, or whenever the disk is forced to spin up by 100a cache miss. The disk can then be spun down in the periods of inactivity. 101 102If you want to find out which process caused the disk to spin up, you can 103gather information by setting the flag /proc/sys/vm/block_dump. When this flag 104is set, Linux reports all disk read and write operations that take place, and 105all block dirtyings done to files. This makes it possible to debug why a disk 106needs to spin up, and to increase battery life even more. The output of 107block_dump is written to the kernel output, and it can be retrieved using 108"dmesg". When you use block_dump and your kernel logging level also includes 109kernel debugging messages, you probably want to turn off klogd, otherwise 110the output of block_dump will be logged, causing disk activity that is not 111normally there. 112 113 114Configuration 115------------- 116 117The laptop mode configuration file is located in /etc/default/laptop-mode on 118Debian-based systems, or in /etc/sysconfig/laptop-mode on other systems. It 119contains the following options: 120 121MAX_AGE: 122 123Maximum time, in seconds, of hard drive spindown time that you are 124comfortable with. Worst case, it's possible that you could lose this 125amount of work if your battery fails while you're in laptop mode. 126 127MINIMUM_BATTERY_MINUTES: 128 129Automatically disable laptop mode if the remaining number of minutes of 130battery power is less than this value. Default is 10 minutes. 131 132AC_HD/BATT_HD: 133 134The idle timeout that should be set on your hard drive when laptop mode 135is active (BATT_HD) and when it is not active (AC_HD). The defaults are 13620 seconds (value 4) for BATT_HD and 2 hours (value 244) for AC_HD. The 137possible values are those listed in the manual page for "hdparm" for the 138"-S" option. 139 140HD: 141 142The devices for which the spindown timeout should be adjusted by laptop mode. 143Default is /dev/hda. If you specify multiple devices, separate them by a space. 144 145READAHEAD: 146 147Disk readahead, in 512-byte sectors, while laptop mode is active. A large 148readahead can prevent disk accesses for things like executable pages (which are 149loaded on demand while the application executes) and sequentially accessed data 150(MP3s). 151 152DO_REMOUNTS: 153 154The control script automatically remounts any mounted journaled filesystems 155with appropriate commit interval options. When this option is set to 0, this 156feature is disabled. 157 158DO_REMOUNT_NOATIME: 159 160When remounting, should the filesystems be remounted with the noatime option? 161Normally, this is set to "1" (enabled), but there may be programs that require 162access time recording. 163 164DIRTY_RATIO: 165 166The percentage of memory that is allowed to contain "dirty" or unsaved data 167before a writeback is forced, while laptop mode is active. Corresponds to 168the /proc/sys/vm/dirty_ratio sysctl. 169 170DIRTY_BACKGROUND_RATIO: 171 172The percentage of memory that is allowed to contain "dirty" or unsaved data 173after a forced writeback is done due to an exceeding of DIRTY_RATIO. Set 174this nice and low. This corresponds to the /proc/sys/vm/dirty_background_ratio 175sysctl. 176 177Note that the behaviour of dirty_background_ratio is quite different 178when laptop mode is active and when it isn't. When laptop mode is inactive, 179dirty_background_ratio is the threshold percentage at which background writeouts 180start taking place. When laptop mode is active, however, background writeouts 181are disabled, and the dirty_background_ratio only determines how much writeback 182is done when dirty_ratio is reached. 183 184DO_CPU: 185 186Enable CPU frequency scaling when in laptop mode. (Requires CPUFreq to be setup. 187See Documentation/cpu-freq/user-guide.txt for more info. Disabled by default.) 188 189CPU_MAXFREQ: 190 191When on battery, what is the maximum CPU speed that the system should use? Legal 192values are "slowest" for the slowest speed that your CPU is able to operate at, 193or a value listed in /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies. 194 195 196Tips & Tricks 197------------- 198 199* Bartek Kania reports getting up to 50 minutes of extra battery life (on top 200 of his regular 3 to 3.5 hours) using a spindown time of 5 seconds (BATT_HD=1). 201 202* You can spin down the disk while playing MP3, by setting disk readahead 203 to 8MB (READAHEAD=16384). Effectively, the disk will read a complete MP3 at 204 once, and will then spin down while the MP3 is playing. (Thanks to Bartek 205 Kania.) 206 207* Drew Scott Daniels observed: "I don't know why, but when I decrease the number 208 of colours that my display uses it consumes less battery power. I've seen 209 this on powerbooks too. I hope that this is a piece of information that 210 might be useful to the Laptop Mode patch or its users." 211 212* In syslog.conf, you can prefix entries with a dash ``-'' to omit syncing the 213 file after every logging. When you're using laptop-mode and your disk doesn't 214 spin down, this is a likely culprit. 215 216* Richard Atterer observed that laptop mode does not work well with noflushd 217 (http://noflushd.sourceforge.net/), it seems that noflushd prevents laptop-mode 218 from doing its thing. 219 220* If you're worried about your data, you might want to consider using a USB 221 memory stick or something like that as a "working area". (Be aware though 222 that flash memory can only handle a limited number of writes, and overuse 223 may wear out your memory stick pretty quickly. Do _not_ use journalling 224 filesystems on flash memory sticks.) 225 226 227Configuration file for control and ACPI battery scripts 228------------------------------------------------------- 229 230This allows the tunables to be changed for the scripts via an external 231configuration file 232 233It should be installed as /etc/default/laptop-mode on Debian, and as 234/etc/sysconfig/laptop-mode on Red Hat, SUSE, Mandrake, and other work-alikes. 235 236--------------------CONFIG FILE BEGIN------------------------------------------- 237# Maximum time, in seconds, of hard drive spindown time that you are 238# comfortable with. Worst case, it's possible that you could lose this 239# amount of work if your battery fails you while in laptop mode. 240#MAX_AGE=600 241 242# Automatically disable laptop mode when the number of minutes of battery 243# that you have left goes below this threshold. 244MINIMUM_BATTERY_MINUTES=10 245 246# Read-ahead, in 512-byte sectors. You can spin down the disk while playing MP3/OGG 247# by setting the disk readahead to 8MB (READAHEAD=16384). Effectively, the disk 248# will read a complete MP3 at once, and will then spin down while the MP3/OGG is 249# playing. 250#READAHEAD=4096 251 252# Shall we remount journaled fs. with appropriate commit interval? (1=yes) 253#DO_REMOUNTS=1 254 255# And shall we add the "noatime" option to that as well? (1=yes) 256#DO_REMOUNT_NOATIME=1 257 258# Dirty synchronous ratio. At this percentage of dirty pages the process 259# which 260# calls write() does its own writeback 261#DIRTY_RATIO=40 262 263# 264# Allowed dirty background ratio, in percent. Once DIRTY_RATIO has been 265# exceeded, the kernel will wake flusher threads which will then reduce the 266# amount of dirty memory to dirty_background_ratio. Set this nice and low, 267# so once some writeout has commenced, we do a lot of it. 268# 269#DIRTY_BACKGROUND_RATIO=5 270 271# kernel default dirty buffer age 272#DEF_AGE=30 273#DEF_UPDATE=5 274#DEF_DIRTY_BACKGROUND_RATIO=10 275#DEF_DIRTY_RATIO=40 276#DEF_XFS_AGE_BUFFER=15 277#DEF_XFS_SYNC_INTERVAL=30 278#DEF_XFS_BUFD_INTERVAL=1 279 280# This must be adjusted manually to the value of HZ in the running kernel 281# on 2.4, until the XFS people change their 2.4 external interfaces to work in 282# centisecs. This can be automated, but it's a work in progress that still 283# needs# some fixes. On 2.6 kernels, XFS uses USER_HZ instead of HZ for 284# external interfaces, and that is currently always set to 100. So you don't 285# need to change this on 2.6. 286#XFS_HZ=100 287 288# Should the maximum CPU frequency be adjusted down while on battery? 289# Requires CPUFreq to be setup. 290# See Documentation/cpu-freq/user-guide.txt for more info 291#DO_CPU=0 292 293# When on battery what is the maximum CPU speed that the system should 294# use? Legal values are "slowest" for the slowest speed that your 295# CPU is able to operate at, or a value listed in: 296# /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies 297# Only applicable if DO_CPU=1. 298#CPU_MAXFREQ=slowest 299 300# Idle timeout for your hard drive (man hdparm for valid values, -S option) 301# Default is 2 hours on AC (AC_HD=244) and 20 seconds for battery (BATT_HD=4). 302#AC_HD=244 303#BATT_HD=4 304 305# The drives for which to adjust the idle timeout. Separate them by a space, 306# e.g. HD="/dev/hda /dev/hdb". 307#HD="/dev/hda" 308 309# Set the spindown timeout on a hard drive? 310#DO_HD=1 311 312--------------------CONFIG FILE END--------------------------------------------- 313 314 315Control script 316-------------- 317 318Please note that this control script works for the Linux 2.4 and 2.6 series (thanks 319to Kiko Piris). 320 321--------------------CONTROL SCRIPT BEGIN---------------------------------------- 322#!/bin/bash 323 324# start or stop laptop_mode, best run by a power management daemon when 325# ac gets connected/disconnected from a laptop 326# 327# install as /sbin/laptop_mode 328# 329# Contributors to this script: Kiko Piris 330# Bart Samwel 331# Micha Feigin 332# Andrew Morton 333# Herve Eychenne 334# Dax Kelson 335# 336# Original Linux 2.4 version by: Jens Axboe 337 338############################################################################# 339 340# Source config 341if [ -f /etc/default/laptop-mode ] ; then 342 # Debian 343 . /etc/default/laptop-mode 344elif [ -f /etc/sysconfig/laptop-mode ] ; then 345 # Others 346 . /etc/sysconfig/laptop-mode 347fi 348 349# Don't raise an error if the config file is incomplete 350# set defaults instead: 351 352# Maximum time, in seconds, of hard drive spindown time that you are 353# comfortable with. Worst case, it's possible that you could lose this 354# amount of work if your battery fails you while in laptop mode. 355MAX_AGE=${MAX_AGE:-'600'} 356 357# Read-ahead, in kilobytes 358READAHEAD=${READAHEAD:-'4096'} 359 360# Shall we remount journaled fs. with appropriate commit interval? (1=yes) 361DO_REMOUNTS=${DO_REMOUNTS:-'1'} 362 363# And shall we add the "noatime" option to that as well? (1=yes) 364DO_REMOUNT_NOATIME=${DO_REMOUNT_NOATIME:-'1'} 365 366# Shall we adjust the idle timeout on a hard drive? 367DO_HD=${DO_HD:-'1'} 368 369# Adjust idle timeout on which hard drive? 370HD="${HD:-'/dev/hda'}" 371 372# spindown time for HD (hdparm -S values) 373AC_HD=${AC_HD:-'244'} 374BATT_HD=${BATT_HD:-'4'} 375 376# Dirty synchronous ratio. At this percentage of dirty pages the process which 377# calls write() does its own writeback 378DIRTY_RATIO=${DIRTY_RATIO:-'40'} 379 380# cpu frequency scaling 381# See Documentation/cpu-freq/user-guide.txt for more info 382DO_CPU=${CPU_MANAGE:-'0'} 383CPU_MAXFREQ=${CPU_MAXFREQ:-'slowest'} 384 385# 386# Allowed dirty background ratio, in percent. Once DIRTY_RATIO has been 387# exceeded, the kernel will wake flusher threads which will then reduce the 388# amount of dirty memory to dirty_background_ratio. Set this nice and low, 389# so once some writeout has commenced, we do a lot of it. 390# 391DIRTY_BACKGROUND_RATIO=${DIRTY_BACKGROUND_RATIO:-'5'} 392 393# kernel default dirty buffer age 394DEF_AGE=${DEF_AGE:-'30'} 395DEF_UPDATE=${DEF_UPDATE:-'5'} 396DEF_DIRTY_BACKGROUND_RATIO=${DEF_DIRTY_BACKGROUND_RATIO:-'10'} 397DEF_DIRTY_RATIO=${DEF_DIRTY_RATIO:-'40'} 398DEF_XFS_AGE_BUFFER=${DEF_XFS_AGE_BUFFER:-'15'} 399DEF_XFS_SYNC_INTERVAL=${DEF_XFS_SYNC_INTERVAL:-'30'} 400DEF_XFS_BUFD_INTERVAL=${DEF_XFS_BUFD_INTERVAL:-'1'} 401 402# This must be adjusted manually to the value of HZ in the running kernel 403# on 2.4, until the XFS people change their 2.4 external interfaces to work in 404# centisecs. This can be automated, but it's a work in progress that still needs 405# some fixes. On 2.6 kernels, XFS uses USER_HZ instead of HZ for external 406# interfaces, and that is currently always set to 100. So you don't need to 407# change this on 2.6. 408XFS_HZ=${XFS_HZ:-'100'} 409 410############################################################################# 411 412KLEVEL="$(uname -r | 413 { 414 IFS='.' read a b c 415 echo $a.$b 416 } 417)" 418case "$KLEVEL" in 419 "2.4"|"2.6") 420 ;; 421 *) 422 echo "Unhandled kernel version: $KLEVEL ('uname -r' = '$(uname -r)')" >&2 423 exit 1 424 ;; 425esac 426 427if [ ! -e /proc/sys/vm/laptop_mode ] ; then 428 echo "Kernel is not patched with laptop_mode patch." >&2 429 exit 1 430fi 431 432if [ ! -w /proc/sys/vm/laptop_mode ] ; then 433 echo "You do not have enough privileges to enable laptop_mode." >&2 434 exit 1 435fi 436 437# Remove an option (the first parameter) of the form option=<number> from 438# a mount options string (the rest of the parameters). 439parse_mount_opts () { 440 OPT="$1" 441 shift 442 echo ",$*," | sed \ 443 -e 's/,'"$OPT"'=[0-9]*,/,/g' \ 444 -e 's/,,*/,/g' \ 445 -e 's/^,//' \ 446 -e 's/,$//' 447} 448 449# Remove an option (the first parameter) without any arguments from 450# a mount option string (the rest of the parameters). 451parse_nonumber_mount_opts () { 452 OPT="$1" 453 shift 454 echo ",$*," | sed \ 455 -e 's/,'"$OPT"',/,/g' \ 456 -e 's/,,*/,/g' \ 457 -e 's/^,//' \ 458 -e 's/,$//' 459} 460 461# Find out the state of a yes/no option (e.g. "atime"/"noatime") in 462# fstab for a given filesystem, and use this state to replace the 463# value of the option in another mount options string. The device 464# is the first argument, the option name the second, and the default 465# value the third. The remainder is the mount options string. 466# 467# Example: 468# parse_yesno_opts_wfstab /dev/hda1 atime atime defaults,noatime 469# 470# If fstab contains, say, "rw" for this filesystem, then the result 471# will be "defaults,atime". 472parse_yesno_opts_wfstab () { 473 L_DEV="$1" 474 OPT="$2" 475 DEF_OPT="$3" 476 shift 3 477 L_OPTS="$*" 478 PARSEDOPTS1="$(parse_nonumber_mount_opts $OPT $L_OPTS)" 479 PARSEDOPTS1="$(parse_nonumber_mount_opts no$OPT $PARSEDOPTS1)" 480 # Watch for a default atime in fstab 481 FSTAB_OPTS="$(awk '$1 == "'$L_DEV'" { print $4 }' /etc/fstab)" 482 if echo "$FSTAB_OPTS" | grep "$OPT" > /dev/null ; then 483 # option specified in fstab: extract the value and use it 484 if echo "$FSTAB_OPTS" | grep "no$OPT" > /dev/null ; then 485 echo "$PARSEDOPTS1,no$OPT" 486 else 487 # no$OPT not found -- so we must have $OPT. 488 echo "$PARSEDOPTS1,$OPT" 489 fi 490 else 491 # option not specified in fstab -- choose the default. 492 echo "$PARSEDOPTS1,$DEF_OPT" 493 fi 494} 495 496# Find out the state of a numbered option (e.g. "commit=NNN") in 497# fstab for a given filesystem, and use this state to replace the 498# value of the option in another mount options string. The device 499# is the first argument, and the option name the second. The 500# remainder is the mount options string in which the replacement 501# must be done. 502# 503# Example: 504# parse_mount_opts_wfstab /dev/hda1 commit defaults,commit=7 505# 506# If fstab contains, say, "commit=3,rw" for this filesystem, then the 507# result will be "rw,commit=3". 508parse_mount_opts_wfstab () { 509 L_DEV="$1" 510 OPT="$2" 511 shift 2 512 L_OPTS="$*" 513 PARSEDOPTS1="$(parse_mount_opts $OPT $L_OPTS)" 514 # Watch for a default commit in fstab 515 FSTAB_OPTS="$(awk '$1 == "'$L_DEV'" { print $4 }' /etc/fstab)" 516 if echo "$FSTAB_OPTS" | grep "$OPT=" > /dev/null ; then 517 # option specified in fstab: extract the value, and use it 518 echo -n "$PARSEDOPTS1,$OPT=" 519 echo ",$FSTAB_OPTS," | sed \ 520 -e 's/.*,'"$OPT"'=//' \ 521 -e 's/,.*//' 522 else 523 # option not specified in fstab: set it to 0 524 echo "$PARSEDOPTS1,$OPT=0" 525 fi 526} 527 528deduce_fstype () { 529 MP="$1" 530 # My root filesystem unfortunately has 531 # type "unknown" in /etc/mtab. If we encounter 532 # "unknown", we try to get the type from fstab. 533 cat /etc/fstab | 534 grep -v '^#' | 535 while read FSTAB_DEV FSTAB_MP FSTAB_FST FSTAB_OPTS FSTAB_DUMP FSTAB_DUMP ; do 536 if [ "$FSTAB_MP" = "$MP" ]; then 537 echo $FSTAB_FST 538 exit 0 539 fi 540 done 541} 542 543if [ $DO_REMOUNT_NOATIME -eq 1 ] ; then 544 NOATIME_OPT=",noatime" 545fi 546 547case "$1" in 548 start) 549 AGE=$((100*$MAX_AGE)) 550 XFS_AGE=$(($XFS_HZ*$MAX_AGE)) 551 echo -n "Starting laptop_mode" 552 553 if [ -d /proc/sys/vm/pagebuf ] ; then 554 # (For 2.4 and early 2.6.) 555 # This only needs to be set, not reset -- it is only used when 556 # laptop mode is enabled. 557 echo $XFS_AGE > /proc/sys/vm/pagebuf/lm_flush_age 558 echo $XFS_AGE > /proc/sys/fs/xfs/lm_sync_interval 559 elif [ -f /proc/sys/fs/xfs/lm_age_buffer ] ; then 560 # (A couple of early 2.6 laptop mode patches had these.) 561 # The same goes for these. 562 echo $XFS_AGE > /proc/sys/fs/xfs/lm_age_buffer 563 echo $XFS_AGE > /proc/sys/fs/xfs/lm_sync_interval 564 elif [ -f /proc/sys/fs/xfs/age_buffer ] ; then 565 # (2.6.6) 566 # But not for these -- they are also used in normal 567 # operation. 568 echo $XFS_AGE > /proc/sys/fs/xfs/age_buffer 569 echo $XFS_AGE > /proc/sys/fs/xfs/sync_interval 570 elif [ -f /proc/sys/fs/xfs/age_buffer_centisecs ] ; then 571 # (2.6.7 upwards) 572 # And not for these either. These are in centisecs, 573 # not USER_HZ, so we have to use $AGE, not $XFS_AGE. 574 echo $AGE > /proc/sys/fs/xfs/age_buffer_centisecs 575 echo $AGE > /proc/sys/fs/xfs/xfssyncd_centisecs 576 echo 3000 > /proc/sys/fs/xfs/xfsbufd_centisecs 577 fi 578 579 case "$KLEVEL" in 580 "2.4") 581 echo 1 > /proc/sys/vm/laptop_mode 582 echo "30 500 0 0 $AGE $AGE 60 20 0" > /proc/sys/vm/bdflush 583 ;; 584 "2.6") 585 echo 5 > /proc/sys/vm/laptop_mode 586 echo "$AGE" > /proc/sys/vm/dirty_writeback_centisecs 587 echo "$AGE" > /proc/sys/vm/dirty_expire_centisecs 588 echo "$DIRTY_RATIO" > /proc/sys/vm/dirty_ratio 589 echo "$DIRTY_BACKGROUND_RATIO" > /proc/sys/vm/dirty_background_ratio 590 ;; 591 esac 592 if [ $DO_REMOUNTS -eq 1 ]; then 593 cat /etc/mtab | while read DEV MP FST OPTS DUMP PASS ; do 594 PARSEDOPTS="$(parse_mount_opts "$OPTS")" 595 if [ "$FST" = 'unknown' ]; then 596 FST=$(deduce_fstype $MP) 597 fi 598 case "$FST" in 599 "ext3"|"reiserfs") 600 PARSEDOPTS="$(parse_mount_opts commit "$OPTS")" 601 mount $DEV -t $FST $MP -o remount,$PARSEDOPTS,commit=$MAX_AGE$NOATIME_OPT 602 ;; 603 "xfs") 604 mount $DEV -t $FST $MP -o remount,$OPTS$NOATIME_OPT 605 ;; 606 esac 607 if [ -b $DEV ] ; then 608 blockdev --setra $(($READAHEAD * 2)) $DEV 609 fi 610 done 611 fi 612 if [ $DO_HD -eq 1 ] ; then 613 for THISHD in $HD ; do 614 /sbin/hdparm -S $BATT_HD $THISHD > /dev/null 2>&1 615 /sbin/hdparm -B 1 $THISHD > /dev/null 2>&1 616 done 617 fi 618 if [ $DO_CPU -eq 1 -a -e /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq ]; then 619 if [ $CPU_MAXFREQ = 'slowest' ]; then 620 CPU_MAXFREQ=`cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq` 621 fi 622 echo $CPU_MAXFREQ > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq 623 fi 624 echo "." 625 ;; 626 stop) 627 U_AGE=$((100*$DEF_UPDATE)) 628 B_AGE=$((100*$DEF_AGE)) 629 echo -n "Stopping laptop_mode" 630 echo 0 > /proc/sys/vm/laptop_mode 631 if [ -f /proc/sys/fs/xfs/age_buffer -a ! -f /proc/sys/fs/xfs/lm_age_buffer ] ; then 632 # These need to be restored, if there are no lm_*. 633 echo $(($XFS_HZ*$DEF_XFS_AGE_BUFFER)) > /proc/sys/fs/xfs/age_buffer 634 echo $(($XFS_HZ*$DEF_XFS_SYNC_INTERVAL)) > /proc/sys/fs/xfs/sync_interval 635 elif [ -f /proc/sys/fs/xfs/age_buffer_centisecs ] ; then 636 # These need to be restored as well. 637 echo $((100*$DEF_XFS_AGE_BUFFER)) > /proc/sys/fs/xfs/age_buffer_centisecs 638 echo $((100*$DEF_XFS_SYNC_INTERVAL)) > /proc/sys/fs/xfs/xfssyncd_centisecs 639 echo $((100*$DEF_XFS_BUFD_INTERVAL)) > /proc/sys/fs/xfs/xfsbufd_centisecs 640 fi 641 case "$KLEVEL" in 642 "2.4") 643 echo "30 500 0 0 $U_AGE $B_AGE 60 20 0" > /proc/sys/vm/bdflush 644 ;; 645 "2.6") 646 echo "$U_AGE" > /proc/sys/vm/dirty_writeback_centisecs 647 echo "$B_AGE" > /proc/sys/vm/dirty_expire_centisecs 648 echo "$DEF_DIRTY_RATIO" > /proc/sys/vm/dirty_ratio 649 echo "$DEF_DIRTY_BACKGROUND_RATIO" > /proc/sys/vm/dirty_background_ratio 650 ;; 651 esac 652 if [ $DO_REMOUNTS -eq 1 ] ; then 653 cat /etc/mtab | while read DEV MP FST OPTS DUMP PASS ; do 654 # Reset commit and atime options to defaults. 655 if [ "$FST" = 'unknown' ]; then 656 FST=$(deduce_fstype $MP) 657 fi 658 case "$FST" in 659 "ext3"|"reiserfs") 660 PARSEDOPTS="$(parse_mount_opts_wfstab $DEV commit $OPTS)" 661 PARSEDOPTS="$(parse_yesno_opts_wfstab $DEV atime atime $PARSEDOPTS)" 662 mount $DEV -t $FST $MP -o remount,$PARSEDOPTS 663 ;; 664 "xfs") 665 PARSEDOPTS="$(parse_yesno_opts_wfstab $DEV atime atime $OPTS)" 666 mount $DEV -t $FST $MP -o remount,$PARSEDOPTS 667 ;; 668 esac 669 if [ -b $DEV ] ; then 670 blockdev --setra 256 $DEV 671 fi 672 done 673 fi 674 if [ $DO_HD -eq 1 ] ; then 675 for THISHD in $HD ; do 676 /sbin/hdparm -S $AC_HD $THISHD > /dev/null 2>&1 677 /sbin/hdparm -B 255 $THISHD > /dev/null 2>&1 678 done 679 fi 680 if [ $DO_CPU -eq 1 -a -e /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_min_freq ]; then 681 echo `cat /sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq` > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq 682 fi 683 echo "." 684 ;; 685 *) 686 echo "Usage: $0 {start|stop}" 2>&1 687 exit 1 688 ;; 689 690esac 691 692exit 0 693--------------------CONTROL SCRIPT END------------------------------------------ 694 695 696ACPI integration 697---------------- 698 699Dax Kelson submitted this so that the ACPI acpid daemon will 700kick off the laptop_mode script and run hdparm. The part that 701automatically disables laptop mode when the battery is low was 702written by Jan Topinski. 703 704-----------------/etc/acpi/events/ac_adapter BEGIN------------------------------ 705event=ac_adapter 706action=/etc/acpi/actions/ac.sh %e 707----------------/etc/acpi/events/ac_adapter END--------------------------------- 708 709 710-----------------/etc/acpi/events/battery BEGIN--------------------------------- 711event=battery.* 712action=/etc/acpi/actions/battery.sh %e 713----------------/etc/acpi/events/battery END------------------------------------ 714 715 716----------------/etc/acpi/actions/ac.sh BEGIN----------------------------------- 717#!/bin/bash 718 719# ac on/offline event handler 720 721status=`awk '/^state: / { print $2 }' /proc/acpi/ac_adapter/$2/state` 722 723case $status in 724 "on-line") 725 /sbin/laptop_mode stop 726 exit 0 727 ;; 728 "off-line") 729 /sbin/laptop_mode start 730 exit 0 731 ;; 732esac 733---------------------------/etc/acpi/actions/ac.sh END-------------------------- 734 735 736---------------------------/etc/acpi/actions/battery.sh BEGIN------------------- 737#! /bin/bash 738 739# Automatically disable laptop mode when the battery almost runs out. 740 741BATT_INFO=/proc/acpi/battery/$2/state 742 743if [[ -f /proc/sys/vm/laptop_mode ]] 744then 745 LM=`cat /proc/sys/vm/laptop_mode` 746 if [[ $LM -gt 0 ]] 747 then 748 if [[ -f $BATT_INFO ]] 749 then 750 # Source the config file only now that we know we need 751 if [ -f /etc/default/laptop-mode ] ; then 752 # Debian 753 . /etc/default/laptop-mode 754 elif [ -f /etc/sysconfig/laptop-mode ] ; then 755 # Others 756 . /etc/sysconfig/laptop-mode 757 fi 758 MINIMUM_BATTERY_MINUTES=${MINIMUM_BATTERY_MINUTES:-'10'} 759 760 ACTION="`cat $BATT_INFO | grep charging | cut -c 26-`" 761 if [[ ACTION -eq "discharging" ]] 762 then 763 PRESENT_RATE=`cat $BATT_INFO | grep "present rate:" | sed "s/.* \([0-9][0-9]* \).*/\1/" ` 764 REMAINING=`cat $BATT_INFO | grep "remaining capacity:" | sed "s/.* \([0-9][0-9]* \).*/\1/" ` 765 fi 766 if (($REMAINING * 60 / $PRESENT_RATE < $MINIMUM_BATTERY_MINUTES)) 767 then 768 /sbin/laptop_mode stop 769 fi 770 else 771 logger -p daemon.warning "You are using laptop mode and your battery interface $BATT_INFO is missing. This may lead to loss of data when the battery runs out. Check kernel ACPI support and /proc/acpi/battery folder, and edit /etc/acpi/battery.sh to set BATT_INFO to the correct path." 772 fi 773 fi 774fi 775---------------------------/etc/acpi/actions/battery.sh END-------------------- 776 777 778Monitoring tool 779--------------- 780 781Bartek Kania submitted this, it can be used to measure how much time your disk 782spends spun up/down. See Documentation/laptops/dslm.c 783