linux/Documentation
Denys Vlasenko 4a0da71b96 Documentation/sysctl/vm.txt: clarify vfs_cache_pressure description
Existing description is worded in a way which almost encourages setting of
vfs_cache_pressure above 100, possibly way above it.

Users are left in a dark what this numeric value is - an int?  a
percentage?  what the scale is?

As a result, we are getting reports about noticeable performance
degradation from users who have set vfs_cache_pressure to ridiculously
high values - because they thought there is no downside to it.

Via code inspection it's obvious that this value is treated as a
percentage.  This patch changes text to reflect this fact, and adds a
cautionary paragraph advising against setting vfs_cache_pressure sky high.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-06-04 16:54:13 -07:00
..
ABI ACPI and power management updates for 3.16-rc1 2014-06-04 08:57:16 -07:00
accounting
acpi Documentation / ACPI: Fix location of GPIO documentation 2014-05-23 14:39:26 +02:00
aoe
arm Despite relatively young Berlin SoC support, we already have support 2014-05-26 13:41:02 -07:00
arm64 - Documentation clarification on CPU topology and booting requirements 2014-04-08 12:06:03 -07:00
auxdisplay
backlight
blackfin
block
blockdev zram: propagate error to user 2014-04-07 16:36:02 -07:00
bus-devices
cdrom
cgroups Documentation/memcg: warn about incomplete kmemcg state 2014-06-04 16:54:00 -07:00
connector w1: optional bundling of netlink kernel replies 2014-05-27 13:56:21 -07:00
console
cpu-freq PM / OPP: Move cpufreq specific OPP functions out of generic OPP library 2014-05-07 00:39:03 +02:00
cpuidle
cris
crypto
development-process
device-mapper dm thin: add 'no_space_timeout' dm-thin-pool module param 2014-05-20 14:30:36 -04:00
devicetree DeviceTree for 3.16: 2014-06-04 10:02:38 -07:00
DocBook USB driver patches for 3.16-rc1 2014-06-03 09:11:20 -07:00
driver-model Staging driver patches for 3.16-rc1 2014-06-03 08:34:00 -07:00
dvb Linux 3.14-rc5 2014-03-11 06:55:49 -03:00
early-userspace
EDID
extcon
fault-injection
fb doc: spelling error changes 2014-05-05 15:32:05 +02:00
filesystems Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next 2014-06-04 08:50:34 -07:00
firmware_class
fmc
frv
gpio Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next 2014-06-04 08:50:34 -07:00
hid Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next 2014-06-04 08:50:34 -07:00
hwmon New driver for NCT6683D 2014-06-03 11:09:43 -07:00
i2c Documentation: i2c: improve section about flags mangling the protocol 2014-04-06 13:53:48 +02:00
i2o
ia64
ide
infiniband
input Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next 2014-06-04 08:50:34 -07:00
ioctl
isdn
ja_JP Documentation: Update stable address in Chinese and Japanese translations 2014-04-16 14:13:27 -07:00
kbuild kconfig: make allnoconfig disable options behind EMBEDDED and EXPERT 2014-04-07 16:36:09 -07:00
kdump
ko_KR
laptops
leds
m68k
make
memory-devices
metag
mic
mips
misc-devices
mmc
mn10300
mtd doc: spelling error changes 2014-05-05 15:32:05 +02:00
namespaces
netlabel
networking Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next 2014-06-04 08:50:34 -07:00
nfc
parisc
PCI
pcmcia
phy phy: Add new Exynos USB 2.0 PHY driver 2014-03-08 12:39:44 +05:30
power Merge branch 'pm-cpufreq' 2014-06-03 23:13:20 +02:00
powerpc doc: spelling error changes 2014-05-05 15:32:05 +02:00
pps
prctl
pti
ptp ptp: Fix compiler warnings in the testptp utility 2014-03-27 14:51:47 -04:00
rapidio rapidio: rework device hierarchy and introduce mport class of devices 2014-04-07 16:36:07 -07:00
RCU documentation: Update API documentation 2014-04-29 08:38:53 -07:00
s390 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next 2014-06-04 08:50:34 -07:00
scheduler asm/system.h: clean asm/system.h from docs 2014-04-07 16:36:11 -07:00
scsi [SCSI] megaraid_sas: Version and Changelog update 2014-03-15 10:19:21 -07:00
security doc: spelling error changes 2014-05-05 15:32:05 +02:00
serial tty/serial: Add GPIOLIB helpers for controlling modem lines 2014-05-28 12:49:14 -07:00
sh
sound doc: spelling error changes 2014-05-05 15:32:05 +02:00
spi Merge remote-tracking branches 'spi/topic/s3c64xx', 'spi/topic/sc18is602', 'spi/topic/sh-hspi', 'spi/topic/sh-msiof', 'spi/topic/sh-sci', 'spi/topic/sirf' and 'spi/topic/spidev' into spi-next 2014-03-30 00:51:34 +00:00
sysctl Documentation/sysctl/vm.txt: clarify vfs_cache_pressure description 2014-06-04 16:54:13 -07:00
target
thermal
timers
tpm
trace Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next 2014-06-04 08:50:34 -07:00
usb Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next 2014-06-04 08:50:34 -07:00
vDSO
video4linux [media] s5p-fimc: Remove reference to outdated macro 2014-03-14 10:37:43 -03:00
virtual Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next 2014-06-04 08:50:34 -07:00
vm mm/memory-failure.c: support use of a dedicated thread to handle SIGBUS(BUS_MCEERR_AO) 2014-06-04 16:54:13 -07:00
w1 w1: optional bundling of netlink kernel replies 2014-05-27 13:56:21 -07:00
watchdog watchdog: it87_wdt: Work around non-working CIR interrupts 2014-03-31 13:33:55 +02:00
wimax
x86 doc: spelling error changes 2014-05-05 15:32:05 +02:00
xtensa
zh_CN driver core fixes for 3.15-rc2 2014-04-18 16:59:52 -07:00
.gitignore
00-INDEX Merge branch 'x86-nuke-platforms-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-04-02 13:15:58 -07:00
applying-patches.txt
assoc_array.txt
atomic_ops.txt arch,doc: Convert smp_mb__*() 2014-04-18 14:20:48 +02:00
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 doc: Note need of bc in the kernel build from 3.10 onwards 2014-05-19 16:27:20 +02:00
circular-buffers.txt
clk.txt Documentation: clk: Add locking documentation 2014-03-19 14:56:06 -07:00
coccinelle.txt
CodingStyle
cpu-hotplug.txt Doc/cpu-hotplug: Specify race-free way to register CPU hotplug callbacks 2014-03-20 13:43:40 +01:00
cpu-load.txt
cputopology.txt
crc32.txt
dcdbas.txt
debugging-modules.txt
debugging-via-ohci1394.txt firewire: revert to 4 GB RDMA, fix protocols using Memory Space 2014-05-29 15:50:30 +02:00
dell_rbu.txt
devices.txt Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media 2014-04-04 09:50:07 -07:00
digsig.txt
DMA-API-HOWTO.txt DMA-API: Update dma_pool_create ()and dma_pool_alloc() descriptions 2014-05-26 17:28:28 -06:00
DMA-API.txt DMA-API: Capitalize "CPU" consistently 2014-05-26 17:28:27 -06:00
DMA-attributes.txt doc: spelling error changes 2014-05-05 15:32:05 +02:00
dma-buf-sharing.txt doc: spelling error changes 2014-05-05 15:32:05 +02:00
DMA-ISA-LPC.txt DMA-API: Clarify physical/bus address distinction 2014-05-20 16:54:21 -06:00
dmaengine.txt
dmatest.txt
dontdiff Documentation: LLVMLinux: Update Documentation/dontdiff 2014-04-09 13:44:34 -07:00
dynamic-debug-howto.txt doc: spelling error changes 2014-05-05 15:32:05 +02:00
edac.txt Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial into next 2014-06-04 08:50:34 -07:00
efi-stub.txt
eisa.txt
email-clients.txt Documentation: update thunderbird email client settings 2014-05-25 12:39:00 -07:00
flexible-arrays.txt
futex-requeue-pi.txt doc: fix double words 2014-03-21 13:16:58 +01:00
gcov.txt
highuid.txt
HOWTO
hsi.txt Documentation: HSI: Add some general description for the HSI subsystem 2014-05-04 09:49:46 +02:00
hw_random.txt
hwspinlock.txt
init.txt
initrd.txt
intel_txt.txt
Intel-IOMMU.txt
io_ordering.txt
io-mapping.txt
iostats.txt
IPMI.txt
IRQ-affinity.txt
IRQ-domain.txt
IRQ.txt
irqflags-tracing.txt asm/system.h: clean asm/system.h from docs 2014-04-07 16:36:11 -07:00
isapnp.txt
java.txt Documentation: update java sample wrapper for java 7 2014-05-25 12:39:00 -07:00
kernel-doc-nano-HOWTO.txt
kernel-docs.txt
kernel-parameters.txt cma: add placement specifier for "cma=" kernel parameter 2014-06-04 16:53:57 -07:00
kernel-per-CPU-kthreads.txt
kmemcheck.txt doc: fix double words 2014-03-21 13:16:58 +01:00
kmemleak.txt Documentation/kmemleak.txt: updates 2014-04-03 16:21:27 -07:00
kobject.txt
kprobes.txt
kref.txt
ldm.txt
local_ops.txt
lockdep-design.txt
lockstat.txt
lockup-watchdogs.txt
logo.gif
logo.txt
magic-number.txt Documentation/serial: Delete obsolete driver documentation 2014-04-16 14:20:34 -07:00
Makefile
ManagementStyle
md.txt
media-framework.txt
memory-barriers.txt arch,doc: Convert smp_mb__*() 2014-04-18 14:20:48 +02:00
memory-hotplug.txt memory-hotplug: update documentation to hide information about SECTIONS and remove end_phys_index 2014-06-04 16:53:58 -07:00
module-signing.txt Nothing major: the stricter permissions checking for sysfs broke 2014-04-06 09:38:07 -07:00
mono.txt
mutex-design.txt
nommu-mmap.txt
numastat.txt
oops-tracing.txt Use 'E' instead of 'X' for unsigned module taint flag. 2014-03-31 14:52:43 +10:30
padata.txt
parport-lowlevel.txt
parport.txt
percpu-rw-semaphore.txt
phy.txt
pi-futex.txt
pinctrl.txt
pnp.txt
preempt-locking.txt
printk-formats.txt doc: printk-formats: do not mention casts for u64/s64 2014-05-05 15:32:42 +02:00
pwm.txt
ramoops.txt
rbtree.txt doc: spelling error changes 2014-05-05 15:32:05 +02:00
remoteproc.txt
rfkill.txt doc: spelling error changes 2014-05-05 15:32:05 +02:00
robust-futex-ABI.txt
robust-futexes.txt doc: spelling error changes 2014-05-05 15:32:05 +02:00
rpmsg.txt
rt-mutex-design.txt
rt-mutex.txt
rtc.txt
SAK.txt
SecurityBugs
serial-console.txt
sgi-ioc4.txt
SM501.txt
smsc_ece1099.txt
sparse.txt
spinlocks.txt
stable_api_nonsense.txt
stable_kernel_rules.txt stable_kernel_rules: spelling/word usage 2014-04-16 14:13:26 -07:00
static-keys.txt
SubmitChecklist
SubmittingDrivers
SubmittingPatches Documentation/SubmittingPatches: update some dead URLs 2014-04-03 16:21:27 -07:00
svga.txt
sysfs-rules.txt
sysrq.txt
this_cpu_ops.txt
unaligned-memory-access.txt
unicode.txt
unshare.txt
vfio.txt
VGA-softcursor.txt
vgaarbiter.txt
video-output.txt
vme_api.txt
volatile-considered-harmful.txt
workqueue.txt
ww-mutex-design.txt
xz.txt
zorro.txt