David Rientjes 2da02997e0 mm: add dirty_background_bytes and dirty_bytes sysctls ... This change introduces two new sysctls to /proc/sys/vm: dirty_background_bytes and dirty_bytes. dirty_background_bytes is the counterpart to dirty_background_ratio and dirty_bytes is the counterpart to dirty_ratio. With growing memory capacities of individual machines, it's no longer sufficient to specify dirty thresholds as a percentage of the amount of dirtyable memory over the entire system. dirty_background_bytes and dirty_bytes specify quantities of memory, in bytes, that represent the dirty limits for the entire system. If either of these values is set, its value represents the amount of dirty memory that is needed to commence either background or direct writeback. When a `bytes' or `ratio' file is written, its counterpart becomes a function of the written value. For example, if dirty_bytes is written to be 8096, 8K of memory is required to commence direct writeback. dirty_ratio is then functionally equivalent to 8K / the amount of dirtyable memory: dirtyable_memory = free pages + mapped pages + file cache dirty_background_bytes = dirty_background_ratio * dirtyable_memory -or- dirty_background_ratio = dirty_background_bytes / dirtyable_memory AND dirty_bytes = dirty_ratio * dirtyable_memory -or- dirty_ratio = dirty_bytes / dirtyable_memory Only one of dirty_background_bytes and dirty_background_ratio may be specified at a time, and only one of dirty_bytes and dirty_ratio may be specified. When one sysctl is written, the other appears as 0 when read. The `bytes' files operate on a page size granularity since dirty limits are compared with ZVC values, which are in page units. Prior to this change, the minimum dirty_ratio was 5 as implemented by get_dirty_limits() although /proc/sys/vm/dirty_ratio would show any user written value between 0 and 100. This restriction is maintained, but dirty_bytes has a lower limit of only one page. Also prior to this change, the dirty_background_ratio could not equal or exceed dirty_ratio. This restriction is maintained in addition to restricting dirty_background_bytes. If either background threshold equals or exceeds that of the dirty threshold, it is implicitly set to half the dirty threshold. Acked-by: Peter Zijlstra <peterz@infradead.org> Cc: Dave Chinner <david@fromorbit.com> Cc: Christoph Lameter <cl@linux-foundation.org> Signed-off-by: David Rientjes <rientjes@google.com> Cc: Andrea Righi <righi.andrea@gmail.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2009-01-06 15:59:03 -08:00
..
ABI	mm: show node to memory section relationship with symlinks in sysfs	2009-01-06 15:59:00 -08:00
DocBook	WAN: syncppp.c is no longer used by any kernel code. Remove it.	2008-11-22 02:49:48 +01:00
PCI	Create/use more directory structure in the Documentation/ tree.	2008-11-14 17:28:53 +00:00
RCU	Merge branch 'core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2008-12-30 16:10:19 -08:00
accounting	.gitignore updates	2008-10-30 11:38:45 -07:00
acpi	ACPI: update debug parameter documentation	2008-11-07 21:45:29 -05:00
aoe	…
arm	Merge branch 'for-rmk' of git://git.kernel.org/pub/scm/linux/kernel/git/ycmiao/pxa-linux-2.6 into devel	2008-12-29 18:08:11 +00:00
auxdisplay	.gitignore updates	2008-10-30 11:38:45 -07:00
blackfin	Blackfin arch: add supporting for kgdb	2008-10-13 14:07:19 +08:00
block	Documentation: remove reference to ll_rw_blk.c and moved drivers/block/elevator.c	2008-12-29 08:28:43 +01:00
blockdev	Create/use more directory structure in the Documentation/ tree.	2008-11-14 17:28:53 +00:00
cdrom	doc/cdrom: Trvial documentation error, file not present	2008-10-10 08:22:44 +02:00
cgroups	freezer_cg: disable writing freezer.state of root cgroup	2008-11-12 17:17:16 -08:00
connector	.gitignore updates	2008-10-30 11:38:45 -07:00
console	…
controllers	sched: add hierarchical accounting to cpu accounting controller	2008-11-11 12:13:28 +01:00
cpu-freq	doc: Update sh cpufreq documentation.	2008-12-22 18:44:47 +09:00
cpuidle	…
cris	fix random typos	2008-10-16 11:21:30 -07:00
crypto	…
development-process	Add the development process document	2008-10-16 11:51:30 -06:00
device-mapper	…
driver-model	…
dvb	V4L/DVB (9812): [PATCH] short help for Technisat cards to select the right configuration	2008-12-30 09:38:35 -02:00
early-userspace	…
fault-injection	…
fb	[ARM] pxafb: add support for overlay1 and overlay2 as framebuffer devices	2008-12-29 18:00:04 +08:00
filesystems	mm: add dirty_background_bytes and dirty_bytes sysctls	2009-01-06 15:59:03 -08:00
firmware_class	…
frv	…
hwmon	adt7462: new hwmon driver	2008-11-12 17:17:17 -08:00
i2c	i2c: The i2c mailing list is moving	2008-10-30 15:55:47 +01:00
i2o	…
ia64	.gitignore updates	2008-10-30 11:38:45 -07:00
ide	…
infiniband	…
input	Input: fix the example of an input device driver	2008-11-11 11:41:49 -05:00
ioctl	UBI: document UBI ioctls	2008-12-09 15:59:07 +02:00
isdn	Rationalise Randy's address a bit	2008-10-30 11:38:47 -07:00
ja_JP	HOWTO: Sync patch for jp_JP/HOWTO	2008-10-29 15:03:50 -07:00
kbuild	kbuild: document environment variables	2009-01-02 20:43:25 +01:00
kdump	powerpc: Support for relocatable kdump kernel	2008-10-22 15:01:22 +11:00
ko_KR	…
laptops	Merge branch 'linus' into test	2008-10-23 00:11:07 -04:00
lguest	lguest: move the initial guest page table creation code to the host	2008-12-30 09:26:11 +10:30
m68k	…
make	…
mips	…
mn10300	…
mtd	[MTD] [NAND] nand_ecc.c: rewrite for improved performance	2008-08-16 10:55:33 +01:00
namespaces	…
netlabel	…
networking	dccp ccid-2: Phase out the use of boolean Ack Vector sysctl	2008-12-08 01:19:06 -08:00
parisc	…
pcmcia	.gitignore updates	2008-10-30 11:38:45 -07:00
power	pm: document use of RTC in pm_trace	2008-10-16 11:21:29 -07:00
powerpc	gianfar: Convert gianfar to an of_platform_driver	2008-12-16 15:29:15 -08:00
prctl	…
s390	[S390] cio: Exorcise cio_msg= from documentation.	2008-10-10 21:33:49 +02:00
scheduler	Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2008-12-28 12:27:58 -08:00
scsi	[SCSI] cxgb3i: Add cxgb3i iSCSI driver.	2008-12-30 10:45:33 -06:00
serial	Create/use more directory structure in the Documentation/ tree.	2008-11-14 17:28:53 +00:00
sh	sh: Kill off remaining CONFIG_SH_KGDB bits.	2008-12-22 18:44:05 +09:00
sound	Merge branch 'topic/oxygen' into to-push	2008-12-25 11:40:30 +01:00
sparc	sparc: Remove Documentation/sparc/sbus_drivers.txt	2008-08-29 02:15:25 -07:00
spi	spi documentation: use __initdata on struct	2008-12-01 19:55:24 -08:00
sysctl	mm: add dirty_background_bytes and dirty_bytes sysctls	2009-01-06 15:59:03 -08:00
telephony	remove mention of CONFIG_KMOD from documentation	2008-07-22 19:24:29 +10:00
thermal	…
timers	hpet: /dev/hpet - fixes and cleanup	2008-07-31 18:45:41 +02:00
tracers	tracing, doc: update mmiotrace documentation	2008-11-23 20:33:24 +01:00
uml	…
usb	Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6 into for-upstream	2009-01-02 13:17:13 +00:00
video4linux	V4L/DVB (10157): Add USB ID for the Sil4701 radio from DealExtreme	2009-01-02 17:13:56 -02:00
vm	.gitignore updates	2008-10-30 11:38:45 -07:00
w1	hdq: documentation for OMAP HDQ	2008-11-12 17:17:18 -08:00
watchdog	.gitignore updates	2008-10-30 11:38:45 -07:00
x86	Merge branches 'x86/apic', 'x86/cleanups', 'x86/cpufeature', 'x86/crashdump', 'x86/debug', 'x86/defconfig', 'x86/detect-hyper', 'x86/doc', 'x86/dumpstack', 'x86/early-printk', 'x86/fpu', 'x86/idle', 'x86/io', 'x86/memory-corruption-check', 'x86/microcode', 'x86/mm', 'x86/mtrr', 'x86/nmi-watchdog', 'x86/pat2', 'x86/pci-ioapic-boot-irq-quirks', 'x86/ptrace', 'x86/quirks', 'x86/reboot', 'x86/setup-memory', 'x86/signal', 'x86/sparse-fixes', 'x86/time', 'x86/uv' and 'x86/xen' into x86/core	2008-12-23 16:27:23 +01:00
zh_CN	…
00-INDEX	Merge branch 'doc-subdirs' of git://git.kernel.org/pub/scm/linux/kernel/git/rdunlap/linux-docs	2008-11-15 11:51:03 -08:00
BUG-HUNTING	…
Changes	…
CodingStyle	documentation: update CodingStyle tips for Emacs users	2008-07-25 10:53:29 -07:00
DMA-API.txt	DMA-API.txt: fix description of pci_map_sg/dma_map_sg scatterlists handling	2008-12-01 19:55:24 -08:00
DMA-ISA-LPC.txt	…
DMA-attributes.txt	powerpc/cell: Add DMA_ATTR_WEAK_ORDERING dma attribute and use in Cell IOMMU code	2008-07-22 10:39:36 +10:00
DMA-mapping.txt	Documentation/DMA-mapping.txt: update for pci_dma_mapping_error() changes	2008-09-23 08:09:14 -07:00
HOWTO	Remove Andrew Morton's http://www.zip.com.au/~akpm/	2008-10-16 11:21:32 -07:00
IO-mapping.txt	…
IPMI.txt	…
IRQ-affinity.txt	…
IRQ.txt	…
Intel-IOMMU.txt	Documentation cleanup: trivial misspelling, punctuation, and grammar corrections.	2008-07-26 12:00:06 -07:00
Makefile	docsrc: build Documentation/ sources	2008-08-12 16:07:30 -07:00
ManagementStyle	docs: fix ManagementStyle book name	2008-10-30 11:38:46 -07:00
SAK.txt	Remove Andrew Morton's old email accounts	2008-10-16 11:21:32 -07:00
SELinux.txt	selinux: add support for installing a dummy policy (v2)	2008-08-27 08:54:08 +10:00
SM501.txt	…
SecurityBugs	…
Smack.txt	…
SubmitChecklist	documentation: explain memory barriers	2008-10-16 11:21:32 -07:00
SubmittingDrivers	Remove Andrew Morton's old email accounts	2008-10-16 11:21:32 -07:00
SubmittingPatches	Merge branch 'docs' of git://git.lwn.net/linux-2.6	2008-10-16 12:18:16 -07:00
VGA-softcursor.txt	…
applying-patches.txt	…
atomic_ops.txt	…
basic_profiling.txt	…
binfmt_misc.txt	…
braille-console.txt	…
bt8xxgpio.txt	gpio: add bt8xxgpio driver	2008-07-25 10:53:30 -07:00
c2port.txt	Add c2 port support	2008-11-12 17:17:18 -08:00
cachetlb.txt	…
cpu-hotplug.txt	x86: use possible_cpus=NUM to extend the possible cpus allowed	2008-12-18 12:08:05 +01:00
cpu-load.txt	…
cpusets.txt	container freezer: document the cgroup freezer subsystem.	2008-10-20 08:52:34 -07:00
cputopology.txt	sysfs: add documentation to cputopology.txt for system cpumasks	2008-12-19 17:47:12 +10:30
credentials.txt	CRED: Documentation	2008-11-14 10:39:26 +11:00
dcdbas.txt	…
debugging-modules.txt	…
debugging-via-ohci1394.txt	…
dell_rbu.txt	…
devices.txt	USB: add USB test and measurement class driver	2008-10-17 14:40:51 -07:00
dontdiff	dontdiff: more updates to be closer to gitignore	2008-10-16 11:21:31 -07:00
edac.txt	Documentation cleanup: trivial misspelling, punctuation, and grammar corrections.	2008-07-26 12:00:06 -07:00
eisa.txt	…
email-clients.txt	Documentation/email-clients.txt: add some info about gmail	2008-11-06 15:41:19 -08:00
exception.txt	…
feature-removal-schedule.txt	remove ide-scsi	2009-01-02 16:12:51 +01:00
ftrace.txt	ftrace: improve documentation	2008-11-28 13:15:14 +01:00
gpio.txt	gpiolib: request/free hooks	2008-10-16 11:21:40 -07:00
highuid.txt	…
hw_random.txt	…
ics932s401	ics932s401: new clock generator chip driver	2008-11-12 17:17:18 -08:00
initrd.txt	…
io-mapping.txt	io mapping: improve documentation	2008-11-03 18:21:44 +01:00
io_ordering.txt	…
iostats.txt	Documentation cleanup: trivial misspelling, punctuation, and grammar corrections.	2008-07-26 12:00:06 -07:00
irqflags-tracing.txt	…
isapnp.txt	…
java.txt	…
kernel-doc-nano-HOWTO.txt	sched: add kernel doc for the completion, fix kernel-doc-nano-HOWTO.txt	2008-08-26 10:26:54 +02:00
kernel-docs.txt	…
kernel-parameters.txt	Merge branch 'for-linus' of git://git390.osdl.marist.edu/pub/scm/linux-2.6	2008-12-28 12:33:21 -08:00
keys-request-key.txt	…
keys.txt	Documentation cleanup: trivial misspelling, punctuation, and grammar corrections.	2008-07-26 12:00:06 -07:00
kobject.txt	kobject: Fix kobject_rename and !CONFIG_SYSFS	2008-10-16 09:24:52 -07:00
kprobes.txt	…
kref.txt	…
ldm.txt	…
leds-class.txt	Documentation cleanup: trivial misspelling, punctuation, and grammar corrections.	2008-07-26 12:00:06 -07:00
local_ops.txt	documentation: local_ops fix on_each_cpu	2008-12-01 13:51:26 +01:00
lockdep-design.txt	…
lockstat.txt	lockstat: contend with points	2008-10-20 15:43:10 +02:00
logo.gif	…
logo.txt	…
magic-number.txt	…
markers.txt	markers: comment marker_synchronize_unregister() on data dependency	2008-11-28 16:47:41 +01:00
mca.txt	…
md.txt	md: Tidy up rdev_size_store a bit:	2008-07-21 14:22:18 +10:00
memory-barriers.txt	…
memory-hotplug.txt	mm: show node to memory section relationship with symlinks in sysfs	2009-01-06 15:59:00 -08:00
memory.txt	…
mono.txt	…
mutex-design.txt	…
nmi_watchdog.txt	x86, nmi-watchdog: update procfs nmi_watchdog file documentation v2	2008-10-30 19:07:04 +01:00
nommu-mmap.txt	…
numastat.txt	…
oops-tracing.txt	…
parport-lowlevel.txt	…
parport.txt	…
pi-futex.txt	…
pnp.txt	…
preempt-locking.txt	…
printk-formats.txt	DOC: add printk-formats.txt	2008-11-12 17:17:17 -08:00
prio_tree.txt	…
rbtree.txt	…
rfkill.txt	rfkill: add master_switch_mode and EPO lock to rfkill and rfkill-input	2008-10-31 19:00:09 -04:00
robust-futex-ABI.txt	…
robust-futexes.txt	…
rt-mutex-design.txt	…
rt-mutex.txt	…
rtc.txt	…
serial-console.txt	…
sgi-ioc4.txt	…
sgi-visws.txt	…
sparse.txt	kbuild: sparse needs CF not CHECKFLAGS	2008-07-25 22:12:39 +02:00
spinlocks.txt	…
stable_api_nonsense.txt	…
stable_kernel_rules.txt	Update stable tree documentation	2008-10-29 15:03:49 -07:00
svga.txt	…
sysfs-rules.txt	sysfs-rules.txt: reword API stability statement	2008-07-21 21:54:59 -07:00
sysrq.txt	Merge branch 'v28-timers-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip	2008-10-20 13:19:56 -07:00
tracepoints.txt	tracepoints: Documentation TPPROTO misspelt in Documentation/tracepoints.txt	2008-11-29 15:13:42 +01:00
unaligned-memory-access.txt	introduce HAVE_EFFICIENT_UNALIGNED_ACCESS Kconfig symbol	2008-07-25 10:53:27 -07:00
unicode.txt	…
unshare.txt	…
video-output.txt	…
volatile-considered-harmful.txt	Documentation cleanup: trivial misspelling, punctuation, and grammar corrections.	2008-07-26 12:00:06 -07:00
voyager.txt	…
zorro.txt	…