Johannes Weiner 795ae7a0de mm: scale kswapd watermarks in proportion to memory ... In machines with 140G of memory and enterprise flash storage, we have seen read and write bursts routinely exceed the kswapd watermarks and cause thundering herds in direct reclaim. Unfortunately, the only way to tune kswapd aggressiveness is through adjusting min_free_kbytes - the system's emergency reserves - which is entirely unrelated to the system's latency requirements. In order to get kswapd to maintain a 250M buffer of free memory, the emergency reserves need to be set to 1G. That is a lot of memory wasted for no good reason. On the other hand, it's reasonable to assume that allocation bursts and overall allocation concurrency scale with memory capacity, so it makes sense to make kswapd aggressiveness a function of that as well. Change the kswapd watermark scale factor from the currently fixed 25% of the tunable emergency reserve to a tunable 0.1% of memory. Beyond 1G of memory, this will produce bigger watermark steps than the current formula in default settings. Ensure that the new formula never chooses steps smaller than that, i.e. 25% of the emergency reserve. On a 140G machine, this raises the default watermark steps - the distance between min and low, and low and high - from 16M to 143M. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Acked-by: Mel Gorman <mgorman@suse.de> Acked-by: Rik van Riel <riel@redhat.com> Acked-by: David Rientjes <rientjes@google.com> Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2016-03-17 15:09:34 -07:00
..
bpf	bpf: fix branch offset adjustment on backjumps after patching ctx expansion	2016-02-10 16:56:47 -05:00
configs
debug	mm/init: Add 'rodata=off' boot cmdline parameter to disable read-only kernel mappings	2016-02-22 08:51:37 +01:00
events	Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2016-03-15 09:32:27 -07:00
gcov	gcov: use within_module() helper.	2015-12-04 22:46:25 +01:00
irq	Power management and ACPI material for v4.6-rc1, part 1	2016-03-16 14:10:53 -07:00
livepatch	livepatch: Cleanup module page permission changes	2015-12-04 22:51:07 +01:00
locking	tags: Fix DEFINE_PER_CPU expansions	2016-03-15 16:55:16 -07:00
power	Power management and ACPI material for v4.6-rc1, part 1	2016-03-16 14:10:53 -07:00
printk	kernel: printk: specify alignment for struct printk_log	2016-01-20 17:09:18 -08:00
rcu	Merge branch 'akpm' (patches from Andrew)	2016-03-16 11:51:08 -07:00
sched	Power management and ACPI material for v4.6-rc1, part 1	2016-03-16 14:10:53 -07:00
time	Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2016-03-15 12:13:56 -07:00
trace	Power management and ACPI material for v4.6-rc1, part 1	2016-03-16 14:10:53 -07:00
.gitignore	certs: add .gitignore to stop git nagging about x509_certificate_list	2015-10-21 15:18:35 +01:00
acct.c
async.c	async: export current_is_async()	2015-11-19 17:51:48 +01:00
audit_fsnotify.c	wrappers for ->i_mutex access	2016-01-22 18:04:28 -05:00
audit_tree.c	audit: audit_tree_match can be boolean	2015-11-04 08:23:51 -05:00
audit_watch.c	wrappers for ->i_mutex access	2016-01-22 18:04:28 -05:00
audit.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security	2016-01-17 19:13:15 -08:00
audit.h	security: Make inode argument of inode_getsecid non-const	2015-12-24 11:09:39 -05:00
auditfilter.c	audit: fix comment block whitespace	2015-11-04 08:23:51 -05:00
auditsc.c	security: Make inode argument of inode_getsecid non-const	2015-12-24 11:09:39 -05:00
backtracetest.c
bounds.c
capability.c
cgroup_freezer.c	cgroup: kill cgrp_ss_priv[CGROUP_CANFORK_COUNT] and friends	2015-12-03 10:24:08 -05:00
cgroup_pids.c	cgroup_pids: fix a typo.	2015-12-14 14:54:37 -05:00
cgroup.c	cgroup: make sure a parent css isn't freed before its children	2016-01-22 10:42:58 -05:00
compat.c
configs.c
context_tracking.c	context_tracking: Switch to new static_branch API	2015-11-24 09:56:43 +01:00
cpu_pm.c	kernel/cpu_pm: fix cpu_cluster_pm_exit comment	2015-09-03 02:42:20 +02:00
cpu.c	cpu/hotplug: Document states better	2016-03-12 20:57:38 +01:00
cpuset.c	cpuset: make mm migration asynchronous	2016-01-22 10:22:46 -05:00
crash_dump.c
cred.c	kmemcg: account certain kmem allocations to memcg	2016-01-14 16:00:49 -08:00
delayacct.c	kmemcg: account certain kmem allocations to memcg	2016-01-14 16:00:49 -08:00
dma.c
elfcore.c
exec_domain.c
exit.c	exit: remove unneeded declaration of exit_mm()	2016-01-20 17:09:18 -08:00
extable.c	kernel/extable.c: remove duplicated include	2015-09-10 13:29:01 -07:00
fork.c	mm: memcontrol: report kernel stack usage in cgroup2 memory.stat	2016-03-17 15:09:34 -07:00
freezer.c
futex_compat.c	ptrace: use fsuid, fsgid, effective creds for fs access checks	2016-01-20 17:09:18 -08:00
futex.c	futex: Replace barrier() in unqueue_me() with READ_ONCE()	2016-03-08 17:04:02 +01:00
groups.c
hung_task.c
irq_work.c	treewide: Remove old email address	2015-11-23 09:44:58 +01:00
jump_label.c	treewide: Remove old email address	2015-11-23 09:44:58 +01:00
kallsyms.c	kallsyms: add support for relative offsets in kallsyms address table	2016-03-15 16:55:16 -07:00
kcmp.c	ptrace: use fsuid, fsgid, effective creds for fs access checks	2016-01-20 17:09:18 -08:00
Kconfig.freezer
Kconfig.hz
Kconfig.locks
Kconfig.preempt
kexec_core.c	kexec: Set IORESOURCE_SYSTEM_RAM for System RAM	2016-01-30 09:49:57 +01:00
kexec_file.c	x86, kexec, nvdimm: Use walk_iomem_res_desc() for iomem search	2016-01-30 09:49:59 +01:00
kexec_internal.h	kexec: move some memembers and definitions within the scope of CONFIG_KEXEC_FILE	2016-01-20 17:09:18 -08:00
kexec.c	kexec: set KEXEC_TYPE_CRASH before sanity_check_segment_list()	2016-01-20 17:09:18 -08:00
kmod.c	kmod: don't run async usermode helper as a child of kworker thread	2015-10-23 17:55:10 +09:00
kprobes.c	perf/x86/hw_breakpoints: Disallow kernel breakpoints unless kprobe-safe	2015-08-04 10:16:54 +02:00
ksysfs.c	rcu: Remove TINY_RCU bloat from pointless boot parameters	2015-12-07 16:59:37 -08:00
kthread.c	kernel/kthread.c:kthread_create_on_node(): clarify documentation	2015-09-04 16:54:41 -07:00
latencytop.c	sched/debug: Make schedstats a runtime tunable that is disabled by default	2016-02-09 11:54:23 +01:00
Makefile	sys_membarrier(): system-wide memory barrier (generic, x86)	2015-09-11 15:21:34 -07:00
membarrier.c	sys_membarrier(): system-wide memory barrier (generic, x86)	2015-09-11 15:21:34 -07:00
memremap.c	mm: fix two typos in comments for to_vmem_altmap()	2016-03-15 16:55:16 -07:00
module_signing.c	KEYS: Merge the type-specific data with the payload data	2015-10-21 15:18:36 +01:00
module-internal.h
module.c	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/livepatching	2016-02-18 16:34:15 -08:00
notifier.c	Merge branch 'x86-asm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2015-09-01 08:40:25 -07:00
nsproxy.c
padata.c
panic.c	printk: do cond_resched() between lines while outputting to consoles	2016-01-16 11:17:25 -08:00
params.c	Nothing exciting, minor tweaks and cleanups.	2015-11-09 15:53:39 -08:00
pid_namespace.c
pid.c	Merge branch 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2016-01-31 15:44:04 -08:00
profile.c	sched/debug: Make schedstats a runtime tunable that is disabled by default	2016-02-09 11:54:23 +01:00
ptrace.c	ptrace: use fsuid, fsgid, effective creds for fs access checks	2016-01-20 17:09:18 -08:00
range.c
reboot.c	kexec: split kexec_load syscall from kexec core code	2015-09-10 13:29:01 -07:00
relay.c	wrappers for ->i_mutex access	2016-01-22 18:04:28 -05:00
resource.c	resource: Export insert_resource and remove_resource	2016-03-09 11:07:20 -08:00
seccomp.c	seccomp: always propagate NO_NEW_PRIVS on tsync	2016-01-27 07:38:25 -08:00
signal.c	signals: avoid random wakeups in sigsuspend()	2016-02-05 18:10:40 -08:00
smp.c	Merge branch 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip	2016-03-15 13:50:29 -07:00
smpboot.c	cpu/hotplug: Unpark smpboot threads from the state machine	2016-03-01 20:36:56 +01:00
smpboot.h	cpu/hotplug: Create hotplug threads	2016-03-01 20:36:56 +01:00
softirq.c	sched/debug: Fix preempt_disable_ip recording for preempt_disable()	2016-02-29 09:53:10 +01:00
stacktrace.c
stop_machine.c	kernel/stop_machine.c: remove CONFIG_SMP dependencies	2016-01-16 11:17:24 -08:00
sys_ni.c	vfs: add copy_file_range syscall and vfs helper	2015-12-01 14:00:53 -05:00
sys.c	prctl: take mmap sem for writing to protect against others	2016-01-20 17:09:18 -08:00
sysctl_binary.c
sysctl.c	mm: scale kswapd watermarks in proportion to memory	2016-03-17 15:09:34 -07:00
task_work.c	task_work: remove fifo ordering guarantee	2015-09-05 13:46:58 -07:00
taskstats.c
test_kprobes.c
torture.c	torture: Consolidate cond_resched_rcu_qs() into stutter_wait()	2015-10-06 11:25:01 -07:00
tracepoint.c	tracepoint: Give priority to probes of tracepoints	2015-10-25 21:33:54 -04:00
tsacct.c	time, acct: Drop irq save & restore from __acct_update_integrals()	2016-02-29 09:53:09 +01:00
uid16.c
up.c
user_namespace.c	kernel/*: switch to memdup_user_nul()	2016-01-04 10:27:55 -05:00
user-return-notifier.c
user.c
utsname_sysctl.c
utsname.c
watchdog.c	watchdog: don't run proc_watchdog_update if new value is same as old	2016-03-17 15:09:34 -07:00
workqueue_internal.h
workqueue.c	tags: Fix DEFINE_PER_CPU expansions	2016-03-15 16:55:16 -07:00