linux/Documentation
Johannes Weiner 57e9cc50f4 mm: vmscan: split khugepaged stats from direct reclaim stats
Direct reclaim stats are useful for identifying a potential source for
application latency, as well as spotting issues with kswapd.  However,
khugepaged currently distorts the picture: as a kernel thread it doesn't
impose allocation latencies on userspace, and it explicitly opts out of
kswapd reclaim.  Its activity showing up in the direct reclaim stats is
misleading.  Counting it as kswapd reclaim could also cause confusion when
trying to understand actual kswapd behavior.

Break out khugepaged from the direct reclaim counters into new
pgsteal_khugepaged, pgdemote_khugepaged, pgscan_khugepaged counters.

Test with a huge executable (CONFIG_READ_ONLY_THP_FOR_FS):

pgsteal_kswapd 1342185
pgsteal_direct 0
pgsteal_khugepaged 3623
pgscan_kswapd 1345025
pgscan_direct 0
pgscan_khugepaged 3623

Link: https://lkml.kernel.org/r/20221026180133.377671-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Reported-by: Eric Bergen <ebergen@meta.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Yang Shi <shy828301@gmail.com>
Cc: Yosry Ahmed <yosryahmed@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-11-30 15:58:41 -08:00
..
ABI memory tier, sysfs: rename attribute "nodes" to "nodelist" 2022-10-28 13:37:22 -07:00
accounting filemap: make the accounting of thrashing more consistent 2022-09-26 19:46:06 -07:00
admin-guide mm: vmscan: split khugepaged stats from direct reclaim stats 2022-11-30 15:58:41 -08:00
arc
arm EFI updates for v6.1 2022-10-09 08:56:54 -07:00
arm64 ARM: 2022-11-06 10:46:59 -08:00
block Documentation: document ublk user recovery feature 2022-10-18 05:12:26 -07:00
bpf Networking changes for 6.1. 2022-10-04 13:38:03 -07:00
cdrom
core-api overflow: Fix kern-doc markup for functions 2022-10-25 14:57:42 -07:00
cpu-freq
crypto
dev-tools docs: kmsan: fix formatting of "Example report" 2022-11-08 15:57:25 -08:00
devicetree ARM: SoC fixes for 6.1, part 2 2022-11-04 14:13:12 -07:00
doc-guide Rust introduction for v6.1-rc1 2022-10-03 16:39:37 -07:00
driver-api Documentation: devres: add missing I2C helper 2022-11-02 21:16:38 +01:00
fault-injection docs: notifier-error-inject: Correct test's name 2022-10-07 10:32:16 -06:00
fb Documentation: fb: udlfb: clean up text and formatting 2022-09-27 13:21:44 -06:00
features
filesystems A handful of relatively simple documentation fixes, plus a set of patches 2022-10-13 10:58:32 -07:00
firmware-guide Merge branches 'acpi-misc', 'acpi-tools' and 'acpi-docs' 2022-10-03 20:03:49 +02:00
firmware_class
fpga
gpu Immutable backlight-detect-refactor branch between acpi, drm-* and pdx86 2022-09-14 12:27:10 +01:00
hid
hwmon hwmon: (corsair-psu) Add USB id of the new HX1500i psu 2022-10-22 06:59:12 -07:00
i2c docs: i2c: slave-interface: return errno when handle I2C_SLAVE_WRITE_REQUESTED 2022-09-28 21:41:59 +02:00
ia64
iio docs: iio: add documentation for BNO055 driver 2022-09-21 18:42:56 +01:00
images
infiniband
input Merge branch 'next' into for-linus 2022-10-09 22:30:23 -07:00
isdn
kbuild Documentation: kbuild: Add description of git for reproducible builds 2022-10-28 00:16:29 +09:00
kernel-hacking Documentation: Fix spelling mistake in hacking.rst 2022-10-24 11:27:51 -06:00
leds
litmus-tests
livepatch
locking Remove duplicate words inside documentation 2022-09-27 13:21:43 -06:00
loongarch
m68k
maintainer
mhi
mips
misc-devices
mm A handful of relatively simple documentation fixes, plus a set of patches 2022-10-13 10:58:32 -07:00
netlabel
networking Random number generator fixes for Linux 6.1-rc1. 2022-10-16 15:27:07 -07:00
nios2
nvdimm
openrisc
parisc
PCI
pcmcia
peci
power
powerpc powerpc/64s: update cpu selection options 2022-09-28 19:22:10 +10:00
process Four small fixes for the docs tree. 2022-11-01 15:11:42 -07:00
RCU There's not a huge amount of activity in the docs tree this time around, 2022-10-03 10:23:32 -07:00
riscv doc: RISC-V: Document that misaligned accesses are supported 2022-10-12 08:58:10 -07:00
rust x86: enable initial Rust support 2022-09-28 09:02:45 +02:00
s390 vfio/mdev: embedd struct mdev_parent in the parent data structure 2022-10-04 12:06:58 -06:00
scheduler docs: scheduler: Update new path for the sysctl knobs 2022-09-27 13:21:42 -06:00
scsi
security landlock: Fix documentation style 2022-09-29 18:43:04 +02:00
sh
sound
sparc
sphinx
sphinx-static
spi
staging docs: put atomic*.txt and memory-barriers.txt into the core-api book 2022-09-29 12:55:06 -06:00
target
timers
tools A handful of relatively simple documentation fixes, plus a set of patches 2022-10-13 10:58:32 -07:00
trace tracing/histogram: Update document for KEYS_MAX size 2022-10-18 15:41:56 -06:00
translations docs/process/howto: Replace C89 with C11 2022-10-24 11:27:51 -06:00
usb
userspace-api media fixes for v6.1-rc2 2022-10-22 15:30:15 -07:00
virt ARM: 2022-10-11 20:07:44 -07:00
w1 Documentation: W1: minor typo corrections 2022-09-27 13:21:44 -06:00
watchdog
x86 - Get rid of a single ksize() usage 2022-10-04 10:12:08 -07:00
xtensa
.gitignore
arch.rst
atomic_bitops.txt
atomic_t.txt
Changes
CodingStyle
conf.py There's not a huge amount of activity in the docs tree this time around, 2022-10-03 10:23:32 -07:00
docutils.conf
dontdiff
index.rst Rust introduction for v6.1-rc1 2022-10-03 16:39:37 -07:00
Kconfig
Makefile
memory-barriers.txt
SubmittingPatches
subsystem-apis.rst docs: Rewrite the front page 2022-09-29 12:55:06 -06:00