ia64/linux-2.6.18-xen.hg

view Documentation/laptop-mode.txt @ 897:329ea0ccb344

balloon: try harder to balloon up under memory pressure.

Currently if the balloon driver is unable to increase the guest's
reservation it assumes the failure was due to reaching its full
allocation, gives up on the ballooning operation and records the limit
it reached as the "hard limit". The driver will not try again until
the target is set again (even to the same value).

However it is possible that ballooning has in fact failed due to
memory pressure in the host and therefore it is desirable to keep
attempting to reach the target in case memory becomes available. The
most likely scenario is that some guests are ballooning down while
others are ballooning up and therefore there is temporary memory
pressure while things stabilise. You would not expect a well behaved
toolstack to ask a domain to balloon to more than its allocation nor
would you expect it to deliberately over-commit memory by setting
balloon targets which exceed the total host memory.

This patch drops the concept of a hard limit and causes the balloon
driver to retry increasing the reservation on a timer in the same
manner as when decreasing the reservation.

Also if we partially succeed in increasing the reservation
(i.e. receive less pages than we asked for) then we may as well keep
those pages rather than returning them to Xen.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
author Keir Fraser <keir.fraser@citrix.com>
date Fri Jun 05 14:01:20 2009 +0100 (2009-06-05)
parents 831230e53067
children
line source
1 How to conserve battery power using laptop-mode
2 -----------------------------------------------
4 Document Author: Bart Samwel (bart@samwel.tk)
5 Date created: January 2, 2004
6 Last modified: December 06, 2004
8 Introduction
9 ------------
11 Laptop mode is used to minimize the time that the hard disk needs to be spun up,
12 to conserve battery power on laptops. It has been reported to cause significant
13 power savings.
15 Contents
16 --------
18 * Introduction
19 * Installation
20 * Caveats
21 * The Details
22 * Tips & Tricks
23 * Control script
24 * ACPI integration
25 * Monitoring tool
28 Installation
29 ------------
31 To use laptop mode, you don't need to set any kernel configuration options
32 or anything. Simply install all the files included in this document, and
33 laptop mode will automatically be started when you're on battery. For
34 your convenience, a tarball containing an installer can be downloaded at:
36 http://www.xs4all.nl/~bsamwel/laptop_mode/tools/
38 To configure laptop mode, you need to edit the configuration file, which is
39 located in /etc/default/laptop-mode on Debian-based systems, or in
40 /etc/sysconfig/laptop-mode on other systems.
42 Unfortunately, automatic enabling of laptop mode does not work for
43 laptops that don't have ACPI. On those laptops, you need to start laptop
44 mode manually. To start laptop mode, run "laptop_mode start", and to
45 stop it, run "laptop_mode stop". (Note: The laptop mode tools package now
46 has experimental support for APM, you might want to try that first.)
49 Caveats
50 -------
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.
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.
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.
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.
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.
77 The Details
78 -----------
80 Laptop mode is controlled by the knob /proc/sys/vm/laptop_mode. This knob is
81 present for all kernels that have the laptop mode patch, regardless of any
82 configuration options. When the knob is set, any physical disk I/O (that might
83 have caused the hard disk to spin up) causes Linux to flush all dirty blocks. The
84 result of this is that after a disk has spun down, it will not be spun up
85 anymore to write dirty blocks, because those blocks had already been written
86 immediately after the most recent read operation. The value of the laptop_mode
87 knob determines the time between the occurrence of disk I/O and when the flush
88 is triggered. A sensible value for the knob is 5 seconds. Setting the knob to
89 0 disables laptop mode.
91 To increase the effectiveness of the laptop_mode strategy, the laptop_mode
92 control 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
94 dirtied are not forced to be written to disk as often. The control script also
95 changes the dirty background ratio, so that background writeback of dirty pages
96 is not done anymore. Combined with a higher commit value (also 10 minutes) for
97 ext3 or ReiserFS filesystems (also done automatically by the control script),
98 this results in concentration of disk activity in a small time interval which
99 occurs only once every 10 minutes, or whenever the disk is forced to spin up by
100 a cache miss. The disk can then be spun down in the periods of inactivity.
102 If you want to find out which process caused the disk to spin up, you can
103 gather information by setting the flag /proc/sys/vm/block_dump. When this flag
104 is set, Linux reports all disk read and write operations that take place, and
105 all block dirtyings done to files. This makes it possible to debug why a disk
106 needs to spin up, and to increase battery life even more. The output of
107 block_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
109 kernel debugging messages, you probably want to turn off klogd, otherwise
110 the output of block_dump will be logged, causing disk activity that is not
111 normally there.
114 Configuration
115 -------------
117 The laptop mode configuration file is located in /etc/default/laptop-mode on
118 Debian-based systems, or in /etc/sysconfig/laptop-mode on other systems. It
119 contains the following options:
121 MAX_AGE:
123 Maximum time, in seconds, of hard drive spindown time that you are
124 confortable with. Worst case, it's possible that you could lose this
125 amount of work if your battery fails while you're in laptop mode.
127 MINIMUM_BATTERY_MINUTES:
129 Automatically disable laptop mode if the remaining number of minutes of
130 battery power is less than this value. Default is 10 minutes.
132 AC_HD/BATT_HD:
134 The idle timeout that should be set on your hard drive when laptop mode
135 is active (BATT_HD) and when it is not active (AC_HD). The defaults are
136 20 seconds (value 4) for BATT_HD and 2 hours (value 244) for AC_HD. The
137 possible values are those listed in the manual page for "hdparm" for the
138 "-S" option.
140 HD:
142 The devices for which the spindown timeout should be adjusted by laptop mode.
143 Default is /dev/hda. If you specify multiple devices, separate them by a space.
145 READAHEAD:
147 Disk readahead, in 512-byte sectors, while laptop mode is active. A large
148 readahead can prevent disk accesses for things like executable pages (which are
149 loaded on demand while the application executes) and sequentially accessed data
150 (MP3s).
152 DO_REMOUNTS:
154 The control script automatically remounts any mounted journaled filesystems
155 with approriate commit interval options. When this option is set to 0, this
156 feature is disabled.
158 DO_REMOUNT_NOATIME:
160 When remounting, should the filesystems be remounted with the noatime option?
161 Normally, this is set to "1" (enabled), but there may be programs that require
162 access time recording.
164 DIRTY_RATIO:
166 The percentage of memory that is allowed to contain "dirty" or unsaved data
167 before a writeback is forced, while laptop mode is active. Corresponds to
168 the /proc/sys/vm/dirty_ratio sysctl.
170 DIRTY_BACKGROUND_RATIO:
172 The percentage of memory that is allowed to contain "dirty" or unsaved data
173 after a forced writeback is done due to an exceeding of DIRTY_RATIO. Set
174 this nice and low. This corresponds to the /proc/sys/vm/dirty_background_ratio
175 sysctl.
177 Note that the behaviour of dirty_background_ratio is quite different
178 when laptop mode is active and when it isn't. When laptop mode is inactive,
179 dirty_background_ratio is the threshold percentage at which background writeouts
180 start taking place. When laptop mode is active, however, background writeouts
181 are disabled, and the dirty_background_ratio only determines how much writeback
182 is done when dirty_ratio is reached.
184 DO_CPU:
186 Enable CPU frequency scaling when in laptop mode. (Requires CPUFreq to be setup.
187 See Documentation/cpu-freq/user-guide.txt for more info. Disabled by default.)
189 CPU_MAXFREQ:
191 When on battery, what is the maximum CPU speed that the system should use? Legal
192 values are "slowest" for the slowest speed that your CPU is able to operate at,
193 or a value listed in /sys/devices/system/cpu/cpu0/cpufreq/scaling_available_frequencies.
196 Tips & Tricks
197 -------------
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).
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.)
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 it's users."
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.
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.
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.)
227 Configuration file for control and ACPI battery scripts
228 -------------------------------------------------------
230 This allows the tunables to be changed for the scripts via an external
231 configuration file
233 It 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.
236 --------------------CONFIG FILE BEGIN-------------------------------------------
237 # Maximum time, in seconds, of hard drive spindown time that you are
238 # confortable 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
242 # Automatically disable laptop mode when the number of minutes of battery
243 # that you have left goes below this threshold.
244 MINIMUM_BATTERY_MINUTES=10
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
252 # Shall we remount journaled fs. with appropriate commit interval? (1=yes)
253 #DO_REMOUNTS=1
255 # And shall we add the "noatime" option to that as well? (1=yes)
256 #DO_REMOUNT_NOATIME=1
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
263 #
264 # Allowed dirty background ratio, in percent. Once DIRTY_RATIO has been
265 # exceeded, the kernel will wake pdflush which will then reduce the amount
266 # of dirty memory to dirty_background_ratio. Set this nice and low, so once
267 # some writeout has commenced, we do a lot of it.
268 #
269 #DIRTY_BACKGROUND_RATIO=5
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
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
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
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
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
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"
309 # Set the spindown timeout on a hard drive?
310 #DO_HD=1
312 --------------------CONFIG FILE END---------------------------------------------
315 Control script
316 --------------
318 Please note that this control script works for the Linux 2.4 and 2.6 series (thanks
319 to Kiko Piris).
321 --------------------CONTROL SCRIPT BEGIN----------------------------------------
322 #!/bin/bash
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
338 #############################################################################
340 # Source config
341 if [ -f /etc/default/laptop-mode ] ; then
342 # Debian
343 . /etc/default/laptop-mode
344 elif [ -f /etc/sysconfig/laptop-mode ] ; then
345 # Others
346 . /etc/sysconfig/laptop-mode
347 fi
349 # Don't raise an error if the config file is incomplete
350 # set defaults instead:
352 # Maximum time, in seconds, of hard drive spindown time that you are
353 # confortable with. Worst case, it's possible that you could lose this
354 # amount of work if your battery fails you while in laptop mode.
355 MAX_AGE=${MAX_AGE:-'600'}
357 # Read-ahead, in kilobytes
358 READAHEAD=${READAHEAD:-'4096'}
360 # Shall we remount journaled fs. with appropriate commit interval? (1=yes)
361 DO_REMOUNTS=${DO_REMOUNTS:-'1'}
363 # And shall we add the "noatime" option to that as well? (1=yes)
364 DO_REMOUNT_NOATIME=${DO_REMOUNT_NOATIME:-'1'}
366 # Shall we adjust the idle timeout on a hard drive?
367 DO_HD=${DO_HD:-'1'}
369 # Adjust idle timeout on which hard drive?
370 HD="${HD:-'/dev/hda'}"
372 # spindown time for HD (hdparm -S values)
373 AC_HD=${AC_HD:-'244'}
374 BATT_HD=${BATT_HD:-'4'}
376 # Dirty synchronous ratio. At this percentage of dirty pages the process which
377 # calls write() does its own writeback
378 DIRTY_RATIO=${DIRTY_RATIO:-'40'}
380 # cpu frequency scaling
381 # See Documentation/cpu-freq/user-guide.txt for more info
382 DO_CPU=${CPU_MANAGE:-'0'}
383 CPU_MAXFREQ=${CPU_MAXFREQ:-'slowest'}
385 #
386 # Allowed dirty background ratio, in percent. Once DIRTY_RATIO has been
387 # exceeded, the kernel will wake pdflush which will then reduce the amount
388 # of dirty memory to dirty_background_ratio. Set this nice and low, so once
389 # some writeout has commenced, we do a lot of it.
390 #
391 DIRTY_BACKGROUND_RATIO=${DIRTY_BACKGROUND_RATIO:-'5'}
393 # kernel default dirty buffer age
394 DEF_AGE=${DEF_AGE:-'30'}
395 DEF_UPDATE=${DEF_UPDATE:-'5'}
396 DEF_DIRTY_BACKGROUND_RATIO=${DEF_DIRTY_BACKGROUND_RATIO:-'10'}
397 DEF_DIRTY_RATIO=${DEF_DIRTY_RATIO:-'40'}
398 DEF_XFS_AGE_BUFFER=${DEF_XFS_AGE_BUFFER:-'15'}
399 DEF_XFS_SYNC_INTERVAL=${DEF_XFS_SYNC_INTERVAL:-'30'}
400 DEF_XFS_BUFD_INTERVAL=${DEF_XFS_BUFD_INTERVAL:-'1'}
402 # This must be adjusted manually to the value of HZ in the running kernel
403 # on 2.4, until the XFS people change their 2.4 external interfaces to work in
404 # centisecs. This can be automated, but it's a work in progress that still needs
405 # some fixes. On 2.6 kernels, XFS uses USER_HZ instead of HZ for external
406 # interfaces, and that is currently always set to 100. So you don't need to
407 # change this on 2.6.
408 XFS_HZ=${XFS_HZ:-'100'}
410 #############################################################################
412 KLEVEL="$(uname -r |
413 {
414 IFS='.' read a b c
415 echo $a.$b
416 }
417 )"
418 case "$KLEVEL" in
419 "2.4"|"2.6")
420 ;;
421 *)
422 echo "Unhandled kernel version: $KLEVEL ('uname -r' = '$(uname -r)')" >&2
423 exit 1
424 ;;
425 esac
427 if [ ! -e /proc/sys/vm/laptop_mode ] ; then
428 echo "Kernel is not patched with laptop_mode patch." >&2
429 exit 1
430 fi
432 if [ ! -w /proc/sys/vm/laptop_mode ] ; then
433 echo "You do not have enough privileges to enable laptop_mode." >&2
434 exit 1
435 fi
437 # Remove an option (the first parameter) of the form option=<number> from
438 # a mount options string (the rest of the parameters).
439 parse_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 }
449 # Remove an option (the first parameter) without any arguments from
450 # a mount option string (the rest of the parameters).
451 parse_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 }
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".
472 parse_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 }
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".
508 parse_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 }
528 deduce_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 }
543 if [ $DO_REMOUNT_NOATIME -eq 1 ] ; then
544 NOATIME_OPT=",noatime"
545 fi
547 case "$1" in
548 start)
549 AGE=$((100*$MAX_AGE))
550 XFS_AGE=$(($XFS_HZ*$MAX_AGE))
551 echo -n "Starting laptop_mode"
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 $AGE > /proc/sys/fs/xfs/xfssyncd_centisecs
576 echo 3000 > /proc/sys/fs/xfs/xfsbufd_centisecs
577 fi
579 case "$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 ;;
690 esac
692 exit 0
693 --------------------CONTROL SCRIPT END------------------------------------------
696 ACPI integration
697 ----------------
699 Dax Kelson submitted this so that the ACPI acpid daemon will
700 kick off the laptop_mode script and run hdparm. The part that
701 automatically disables laptop mode when the battery is low was
702 writen by Jan Topinski.
704 -----------------/etc/acpi/events/ac_adapter BEGIN------------------------------
705 event=ac_adapter
706 action=/etc/acpi/actions/ac.sh %e
707 ----------------/etc/acpi/events/ac_adapter END---------------------------------
710 -----------------/etc/acpi/events/battery BEGIN---------------------------------
711 event=battery.*
712 action=/etc/acpi/actions/battery.sh %e
713 ----------------/etc/acpi/events/battery END------------------------------------
716 ----------------/etc/acpi/actions/ac.sh BEGIN-----------------------------------
717 #!/bin/bash
719 # ac on/offline event handler
721 status=`awk '/^state: / { print $2 }' /proc/acpi/ac_adapter/$2/state`
723 case $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 ;;
732 esac
733 ---------------------------/etc/acpi/actions/ac.sh END--------------------------
736 ---------------------------/etc/acpi/actions/battery.sh BEGIN-------------------
737 #! /bin/bash
739 # Automatically disable laptop mode when the battery almost runs out.
741 BATT_INFO=/proc/acpi/battery/$2/state
743 if [[ -f /proc/sys/vm/laptop_mode ]]
744 then
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'}
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
774 fi
775 ---------------------------/etc/acpi/actions/battery.sh END--------------------
778 Monitoring tool
779 ---------------
781 Bartek Kania submitted this, it can be used to measure how much time your disk
782 spends spun up/down.
784 ---------------------------dslm.c BEGIN-----------------------------------------
785 /*
786 * Simple Disk Sleep Monitor
787 * by Bartek Kania
788 * Licenced under the GPL
789 */
790 #include <unistd.h>
791 #include <stdlib.h>
792 #include <stdio.h>
793 #include <fcntl.h>
794 #include <errno.h>
795 #include <time.h>
796 #include <string.h>
797 #include <signal.h>
798 #include <sys/ioctl.h>
799 #include <linux/hdreg.h>
801 #ifdef DEBUG
802 #define D(x) x
803 #else
804 #define D(x)
805 #endif
807 int endit = 0;
809 /* Check if the disk is in powersave-mode
810 * Most of the code is stolen from hdparm.
811 * 1 = active, 0 = standby/sleep, -1 = unknown */
812 int check_powermode(int fd)
813 {
814 unsigned char args[4] = {WIN_CHECKPOWERMODE1,0,0,0};
815 int state;
817 if (ioctl(fd, HDIO_DRIVE_CMD, &args)
818 && (args[0] = WIN_CHECKPOWERMODE2) /* try again with 0x98 */
819 && ioctl(fd, HDIO_DRIVE_CMD, &args)) {
820 if (errno != EIO || args[0] != 0 || args[1] != 0) {
821 state = -1; /* "unknown"; */
822 } else
823 state = 0; /* "sleeping"; */
824 } else {
825 state = (args[2] == 255) ? 1 : 0;
826 }
827 D(printf(" drive state is: %d\n", state));
829 return state;
830 }
832 char *state_name(int i)
833 {
834 if (i == -1) return "unknown";
835 if (i == 0) return "sleeping";
836 if (i == 1) return "active";
838 return "internal error";
839 }
841 char *myctime(time_t time)
842 {
843 char *ts = ctime(&time);
844 ts[strlen(ts) - 1] = 0;
846 return ts;
847 }
849 void measure(int fd)
850 {
851 time_t start_time;
852 int last_state;
853 time_t last_time;
854 int curr_state;
855 time_t curr_time = 0;
856 time_t time_diff;
857 time_t active_time = 0;
858 time_t sleep_time = 0;
859 time_t unknown_time = 0;
860 time_t total_time = 0;
861 int changes = 0;
862 float tmp;
864 printf("Starting measurements\n");
866 last_state = check_powermode(fd);
867 start_time = last_time = time(0);
868 printf(" System is in state %s\n\n", state_name(last_state));
870 while(!endit) {
871 sleep(1);
872 curr_state = check_powermode(fd);
874 if (curr_state != last_state || endit) {
875 changes++;
876 curr_time = time(0);
877 time_diff = curr_time - last_time;
879 if (last_state == 1) active_time += time_diff;
880 else if (last_state == 0) sleep_time += time_diff;
881 else unknown_time += time_diff;
883 last_state = curr_state;
884 last_time = curr_time;
886 printf("%s: State-change to %s\n", myctime(curr_time),
887 state_name(curr_state));
888 }
889 }
890 changes--; /* Compensate for SIGINT */
892 total_time = time(0) - start_time;
893 printf("\nTotal running time: %lus\n", curr_time - start_time);
894 printf(" State changed %d times\n", changes);
896 tmp = (float)sleep_time / (float)total_time * 100;
897 printf(" Time in sleep state: %lus (%.2f%%)\n", sleep_time, tmp);
898 tmp = (float)active_time / (float)total_time * 100;
899 printf(" Time in active state: %lus (%.2f%%)\n", active_time, tmp);
900 tmp = (float)unknown_time / (float)total_time * 100;
901 printf(" Time in unknown state: %lus (%.2f%%)\n", unknown_time, tmp);
902 }
904 void ender(int s)
905 {
906 endit = 1;
907 }
909 void usage()
910 {
911 puts("usage: dslm [-w <time>] <disk>");
912 exit(0);
913 }
915 int main(int argc, char **argv)
916 {
917 int fd;
918 char *disk = 0;
919 int settle_time = 60;
921 /* Parse the simple command-line */
922 if (argc == 2)
923 disk = argv[1];
924 else if (argc == 4) {
925 settle_time = atoi(argv[2]);
926 disk = argv[3];
927 } else
928 usage();
930 if (!(fd = open(disk, O_RDONLY|O_NONBLOCK))) {
931 printf("Can't open %s, because: %s\n", disk, strerror(errno));
932 exit(-1);
933 }
935 if (settle_time) {
936 printf("Waiting %d seconds for the system to settle down to "
937 "'normal'\n", settle_time);
938 sleep(settle_time);
939 } else
940 puts("Not waiting for system to settle down");
942 signal(SIGINT, ender);
944 measure(fd);
946 close(fd);
948 return 0;
949 }
950 ---------------------------dslm.c END-------------------------------------------