Rik van Riel 34e431b0ae /proc/meminfo: provide estimated available memory ... Many load balancing and workload placing programs check /proc/meminfo to estimate how much free memory is available. They generally do this by adding up "free" and "cached", which was fine ten years ago, but is pretty much guaranteed to be wrong today. It is wrong because Cached includes memory that is not freeable as page cache, for example shared memory segments, tmpfs, and ramfs, and it does not include reclaimable slab memory, which can take up a large fraction of system memory on mostly idle systems with lots of files. Currently, the amount of memory that is available for a new workload, without pushing the system into swap, can be estimated from MemFree, Active(file), Inactive(file), and SReclaimable, as well as the "low" watermarks from /proc/zoneinfo. However, this may change in the future, and user space really should not be expected to know kernel internals to come up with an estimate for the amount of free memory. It is more convenient to provide such an estimate in /proc/meminfo. If things change in the future, we only have to change it in one place. Signed-off-by: Rik van Riel <riel@redhat.com> Reported-by: Erik Mouw <erik.mouw_2@nxp.com> Acked-by: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2014-01-21 16:19:43 -08:00
..
ABI	USB patches for 3.14-rc1	2014-01-20 16:13:02 -08:00
accounting
acpi	GPIO tree bulk changes for v3.14	2014-01-21 10:09:12 -08:00
aoe	aoe: remove do-nothing NAME="%k" term from example udev rules	2013-09-11 15:59:28 -07:00
arm	gpio: samsung: Update documentation	2014-01-07 19:00:59 +01:00
arm64	arm64: Use 42-bit address space with 64K pages	2013-11-05 17:23:52 +00:00
auxdisplay
backlight	backlight: lp855x_bl: support new LP8555 device	2013-11-13 12:09:14 +09:00
blackfin
block	null_blk: set use_per_node_hctx param to false	2013-12-21 09:30:33 -07:00
blockdev	floppy: Correct documentation of driver options when used as a module.	2013-11-08 09:10:31 -07:00
bus-devices
cdrom
cgroups	memcg: support hierarchical memory.numa_stats	2013-11-13 12:09:06 +09:00
connector	connector - documentation: simplify netlink message length assignment	2013-10-02 16:03:51 -04:00
console
cpu-freq	cpufreq: Implement light weight ->target_index() routine	2013-10-25 22:42:24 +02:00
cpuidle	cpuidle: remove cpuidle_unregister_governor()	2013-10-30 01:21:24 +01:00
cris
crypto
development-process
device-mapper	dm cache: update Documentation for invalidate_cblocks's range syntax	2013-12-10 16:35:15 -05:00
devicetree	Highlights:	2014-01-21 11:36:20 -08:00
DocBook	Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media	2013-12-12 11:06:13 -08:00
driver-model	Staging driver tree patches for 3.14-rc1	2014-01-20 15:51:35 -08:00
dvb
early-userspace
EDID
extcon	extcon: fix switch class porting guide (Documentation)	2014-01-07 11:54:28 +09:00
fault-injection
fb
filesystems	/proc/meminfo: provide estimated available memory	2014-01-21 16:19:43 -08:00
firmware_class
fmc	doc: Fix typo "is is" in Documentations	2013-08-27 10:50:52 +02:00
frv
gpio	gpiolib: return -ENOENT if no GPIO mapping exists	2013-12-12 19:33:59 +01:00
hid
hwmon	Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging	2013-11-15 16:35:10 -08:00
i2c	Documentation: i2c: Remove obsolete example	2014-01-09 23:02:46 +01:00
i2o
ia64
ide
infiniband
input	Input: clarify gamepad API ABS values	2013-10-15 23:42:07 -07:00
ioctl	ALSA: add DICE driver	2013-10-17 21:18:32 +02:00
isdn
ja_JP	Documentation: ja_JP: Update broken link to tpp	2013-12-10 23:09:08 -08:00
kbuild	Documentation/kbuild/kconfig.txt: 'make listnewconfig' replaces: yes "" | make oldconfig	2013-10-08 23:51:50 +02:00
kdump
kmsg/s390	s390/zcrypt: add support for EP11 coprocessor cards	2013-12-18 17:37:15 +01:00
ko_KR	Documentation: HOWTO: Updates on subsystem trees, patchwork, -next (vs. -mm) in ko_KR	2014-01-08 15:32:51 -08:00
laptops	thinkpad-acpi: Add mute and mic-mute LED functionality	2013-10-17 14:38:44 +02:00
leds	Documentation: leds-lp5521,lp5523: update device attribute information	2013-08-26 17:22:13 -07:00
m68k
make
memory-devices
metag
mic	misc: mic: Fix endianness issues.	2013-11-27 11:03:38 -08:00
mips
misc-devices	Documentation/misc-devices/mei/mei-amt-version.c: remove unneeded call of mei_deinit()	2014-01-08 15:20:20 -08:00
mmc
mn10300
mtd	doc: Fix typo "is is" in Documentations	2013-08-27 10:50:52 +02:00
namespaces
netlabel
networking	ipv4: improve documentation of ip_no_pmtu_disc	2013-12-17 15:20:15 -05:00
nfc
parisc
PCI	PCI: Update pci_find_slot() description in pci.txt	2013-09-25 15:43:33 -06:00
pcmcia
power	More ACPI and power management updates for 3.13-rc1	2013-11-20 13:25:04 -08:00
powerpc	powerpc: Update the 00-Index in Documentation/powerpc	2013-08-27 14:44:27 +10:00
pps	USB: serial: invoke dcd_change ldisc's handler.	2013-09-26 09:45:40 -07:00
prctl
pti
ptp	ptp: add the PTP_SYS_OFFSET ioctl to the testptp program	2013-09-23 16:46:17 -04:00
rapidio
RCU	Merge branches 'doc.2013.12.03a', 'fixes.2013.12.12a', 'rcutorture.2013.12.03a' and 'sparse.2013.12.12a' into HEAD	2013-12-12 12:35:38 -08:00
s390	s390/s390dbf: add debug_level_enabled() function	2013-10-24 17:16:53 +02:00
scheduler	H8/300 has been dead for several years, the kernel for it has	2013-11-12 14:13:14 +09:00
scsi	SCSI misc on 20130915	2013-09-15 17:41:30 -04:00
security	ima: update IMA-templates.txt documentation	2014-01-03 07:42:59 -05:00
serial	serial: core: delete .set_wake() callback	2013-10-16 13:16:19 -07:00
sh
sound	ASoC: docs: Update the Overview document	2014-01-07 17:56:32 +00:00
spi
sysctl	sched/numa: Drop sysctl_numa_balancing_settle_count sysctl	2013-12-17 15:24:38 +01:00
target	target: Remove TF_CIT_TMPL macro	2013-10-16 13:35:02 -07:00
thermal	thermal: thermal_core: allow binding with limits on bind_params	2013-09-03 09:10:24 -04:00
timers	doc: add missing files to timers/00-INDEX	2013-10-27 21:55:50 +00:00
tpm
trace	Documentation/trace/tracepoints.txt: add links to TRACE_EVENT documentation	2013-11-13 12:09:32 +09:00
usb	doc: usb: Fix typo in Documentation/usb/gadget_configs.txt	2013-10-31 13:31:39 +01:00
vDSO
video4linux
virtual	Merge branch 'kvm-ppc-queue' of git://github.com/agraf/linux-2.6 into queue	2013-11-04 10:20:57 +02:00
vm	x86, mm: do not leak page->ptl for pmd page tables	2013-11-21 16:42:28 -08:00
w1
watchdog
wimax
x86	x86: Add xloadflags bit for EFI runtime support on kexec	2013-12-29 13:09:06 +00:00
xtensa
zh_CN	Documentation: zh_CN: Update broken link to tpp	2013-12-10 23:09:08 -08:00
.gitignore
00-INDEX	doc: fix a typo in Documentation/00-INDEX	2013-08-27 10:53:07 +02:00
applying-patches.txt
assoc_array.txt	KEYS: Fix multiple key add into associative array	2013-12-02 11:24:18 +00:00
atomic_ops.txt
bad_memory.txt
basic_profiling.txt
bcache.txt
binfmt_misc.txt
braille-console.txt
bt8xxgpio.txt
btmrvl.txt
BUG-HUNTING
bus-virt-phys-mapping.txt
cachetlb.txt
Changes	remove obsolete references to powertweak	2013-11-27 20:34:32 -08:00
circular-buffers.txt	documentation: Update circular buffer for load-acquire/store-release	2013-12-03 10:08:57 -08:00
clk.txt
coccinelle.txt
CodingStyle
cpu-hotplug.txt	MAINTAINERS: update Zwane Mwaikambo's e-mail address	2013-11-13 12:09:14 +09:00
cpu-load.txt
cputopology.txt	doc: Documentation/cputopology.txt fix typo	2013-09-04 12:59:47 +02:00
crc32.txt
dcdbas.txt
debugging-modules.txt
debugging-via-ohci1394.txt
dell_rbu.txt
devices.txt	cuse: add fix minor number to /dev/cuse	2013-10-01 16:44:54 +02:00
digsig.txt
DMA-API-HOWTO.txt	DMA-API: provide a helper to set both DMA and coherent DMA masks	2013-09-17 15:32:37 +01:00
DMA-API.txt	DMA-API: provide a helper to set both DMA and coherent DMA masks	2013-09-17 15:32:37 +01:00
DMA-attributes.txt	doc: Documentation/DMA-attributes.txt fix typo	2013-10-14 15:50:53 +02:00
dma-buf-sharing.txt	dma-buf: Expose buffer size to userspace (v2)	2013-09-10 11:36:45 +05:30
DMA-ISA-LPC.txt
dmaengine.txt
dmatest.txt	dmatest: add a 'wait' parameter	2013-11-14 11:04:40 -08:00
dontdiff
dynamic-debug-howto.txt
edac.txt
efi-stub.txt	EFI stub documentation updates	2013-09-25 12:34:32 +01:00
eisa.txt
email-clients.txt
flexible-arrays.txt
futex-requeue-pi.txt
gcov.txt	gcov: compile specific gcov implementation based on gcc version	2013-11-13 12:09:34 +09:00
highuid.txt
HOWTO	Documentation: HOWTO: Update broken links to tpp	2013-12-10 23:09:08 -08:00
hw_random.txt
hwspinlock.txt	doc: documentation/hwspinlock.txt fix typo	2013-08-27 10:46:02 +02:00
init.txt
initrd.txt
Intel-IOMMU.txt
intel_txt.txt
io-mapping.txt
io_ordering.txt
iostats.txt
IPMI.txt
IRQ-affinity.txt
IRQ-domain.txt
IRQ.txt
irqflags-tracing.txt
isapnp.txt
java.txt
kernel-doc-nano-HOWTO.txt
kernel-docs.txt
kernel-parameters.txt	Merge branch 'x86-kaslr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2014-01-20 14:45:50 -08:00
kernel-per-CPU-kthreads.txt	kthread: Add pointer to vmstat-avoidance patch	2013-09-25 06:49:46 -07:00
kmemcheck.txt	Documentation/kmemcheck: update kmemcheck documentation	2013-08-27 10:47:05 +02:00
kmemleak.txt
kobject.txt	kobject: remove kset from sysfs immediately in kset_unregister()	2013-12-07 21:20:11 -08:00
kprobes.txt
kref.txt
ldm.txt
local_ops.txt
lockdep-design.txt
lockstat.txt	lockstat: Report avg wait and hold times	2013-10-09 08:19:08 +02:00
lockup-watchdogs.txt
logo.gif
logo.txt
magic-number.txt
Makefile
ManagementStyle
md.txt
media-framework.txt
memory-barriers.txt	locking/doc: Rename LOCK/UNLOCK to ACQUIRE/RELEASE	2014-01-12 10:37:13 +01:00
memory-hotplug.txt	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial	2013-09-06 09:36:28 -07:00
module-signing.txt	Add Documentation/module-signing.txt file	2013-12-13 15:59:11 +00:00
mono.txt
mutex-design.txt	locking/doc: Update references to kernel/mutex.c	2013-11-11 12:41:33 +01:00
nommu-mmap.txt
numastat.txt
oops-tracing.txt
padata.txt
parport-lowlevel.txt
parport.txt
percpu-rw-semaphore.txt
phy.txt	drivers: phy: add generic PHY framework	2013-09-27 17:35:41 -07:00
pi-futex.txt
pinctrl.txt	pinctrl: Fix some typos and grammar issues in the documentation	2014-01-15 13:59:50 +01:00
pnp.txt
preempt-locking.txt
printk-formats.txt	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial	2013-09-06 09:36:28 -07:00
pwm.txt	Documentation/pwm: Fix trivial typos	2013-10-24 10:51:33 +02:00
ramoops.txt
rbtree.txt
remoteproc.txt
rfkill.txt
robust-futex-ABI.txt	Documentation/robust-futex-API: Count properly to 4	2013-11-30 14:08:28 +01:00
robust-futexes.txt
rpmsg.txt
rt-mutex-design.txt
rt-mutex.txt
rtc.txt
SAK.txt
SecurityBugs
serial-console.txt
sgi-ioc4.txt
sgi-visws.txt
SM501.txt
smsc_ece1099.txt
sparse.txt
spinlocks.txt
stable_api_nonsense.txt
stable_kernel_rules.txt
static-keys.txt
SubmitChecklist
SubmittingDrivers
SubmittingPatches
svga.txt
sysfs-rules.txt
sysrq.txt	sysrq: Allow magic SysRq key functions to be disabled through Kconfig	2013-10-16 13:01:44 -07:00
this_cpu_ops.txt
unaligned-memory-access.txt
unicode.txt
unshare.txt
vfio.txt	vfio: fix documentation	2013-09-05 16:36:21 -06:00
VGA-softcursor.txt
vgaarbiter.txt
video-output.txt
vme_api.txt	VME: Rename vme_slot_get to avoid confusion with reference counting	2013-12-03 11:15:58 -08:00
volatile-considered-harmful.txt
workqueue.txt
ww-mutex-design.txt
xz.txt
zorro.txt	zorro/UAPI: Disintegrate include/linux/zorro*.h	2013-11-26 11:09:08 +01:00