linux/mm
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
..
kasan kasan: add functions to clear stack poison 2016-03-09 15:43:42 -08:00
backing-dev.c mm/backing-dev.c: fix error path in wb_init() 2016-02-11 18:35:48 -08:00
balloon_compaction.c virtio_balloon: fix race between migration and ballooning 2016-01-12 20:47:06 +02:00
bootmem.c x86/mm: Introduce max_possible_pfn 2015-12-06 12:46:31 +01:00
cleancache.c cleancache: constify cleancache_ops structure 2016-01-27 09:09:57 -05:00
cma_debug.c mm/cma_debug: correct size input to bitmap function 2015-07-17 16:39:54 -07:00
cma.c mm/cma.c: suppress warning 2015-11-05 19:34:48 -08:00
cma.h mm: cma: mark cma_bitmap_maxno() inline in header 2015-08-14 15:56:32 -07:00
compaction.c mm, kswapd: replace kswapd compaction with waking up kcompactd 2016-03-17 15:09:34 -07:00
debug.c mm, debug: move bad flags printing to bad_page() 2016-03-15 16:55:16 -07:00
dmapool.c mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd 2015-11-06 17:50:42 -08:00
early_ioremap.c mm/early_ioremap: use offset_in_page macro 2015-11-05 19:34:48 -08:00
fadvise.c writeback: implement and use inode_congested() 2015-06-02 08:33:35 -06:00
failslab.c mm: fault-inject take over bootstrap kmem_cache check 2016-03-15 16:55:16 -07:00
filemap.c mm: remove unnecessary uses of lock_page_memcg() 2016-03-15 16:55:16 -07:00
frame_vector.c mm: fix docbook comment for get_vaddr_frames() 2015-11-05 19:34:48 -08:00
frontswap.c frontswap: allow multiple backends 2015-06-24 17:49:45 -07:00
gup.c mm: retire GUP WARN_ON_ONCE that outlived its usefulness 2016-02-03 08:57:14 -08:00
highmem.c mm/highmem: make kmap cache coloring aware 2014-08-06 18:01:22 -07:00
huge_memory.c thp, vmstats: count deferred split events 2016-03-17 15:09:34 -07:00
hugetlb_cgroup.c mm: make compound_head() robust 2015-11-06 17:50:42 -08:00
hugetlb.c mm/hugetlb: use EOPNOTSUPP in hugetlb sysctl handlers 2016-03-09 15:43:42 -08:00
hwpoison-inject.c hwpoison: use page_cgroup_ino for filtering by memcg 2015-09-10 13:29:01 -07:00
init-mm.c atomic: use <linux/atomic.h> 2011-07-26 16:49:47 -07:00
internal.h mm, kswapd: replace kswapd compaction with waking up kcompactd 2016-03-17 15:09:34 -07:00
interval_tree.c mm: replace vma->sharead.linear with vma->shared 2015-02-10 14:30:31 -08:00
Kconfig mm/Kconfig: remove redundant arch depend for memory hotplug 2016-03-17 15:09:34 -07:00
Kconfig.debug mm/page_poisoning.c: allow for zero poisoning 2016-03-15 16:55:16 -07:00
kmemcheck.c mm: kmemcheck skip object if slab allocation failed 2016-03-15 16:55:16 -07:00
kmemleak-test.c mm/kmemleak-test.c: use pr_fmt for logging 2014-06-06 16:08:18 -07:00
kmemleak.c Revert "gfp: add __GFP_NOACCOUNT" 2016-01-14 16:00:49 -08:00
ksm.c mm/ksm.c: mark stable page dirty 2016-01-15 17:56:32 -08:00
list_lru.c mm: memcontrol: move kmem accounting code to CONFIG_MEMCG 2016-01-20 17:09:18 -08:00
maccess.c mm/maccess.c: actually return -EFAULT from strncpy_from_unsafe 2015-11-05 19:34:48 -08:00
madvise.c mm/madvise: update comment on sys_madvise() 2016-03-15 16:55:16 -07:00
Makefile mm/page_poison.c: enable PAGE_POISONING as a separate option 2016-03-15 16:55:16 -07:00
memblock.c mm/memblock.c: remove unnecessary memblock_type variable 2016-03-15 16:55:16 -07:00
memcontrol.c mm: workingset: make shadow node shrinker memcg aware 2016-03-17 15:09:34 -07:00
memory_hotplug.c mm, memory hotplug: small cleanup in online_pages() 2016-03-17 15:09:34 -07:00
memory-failure.c mm/memory-failure.c: remove useless "undef"s 2016-03-15 16:55:16 -07:00
memory.c mm: cleanup *pte_alloc* interfaces 2016-03-17 15:09:34 -07:00
mempolicy.c mm/mempolicy.c: skip VM_HUGETLB and VM_MIXEDMAP VMA for lazy mbind 2016-03-15 16:55:16 -07:00
mempool.c mm/mempool: avoid KASAN marking mempool poison checks as use-after-free 2016-03-11 16:17:47 -08:00
memtest.c memtest: remove unused header files 2015-09-08 15:35:28 -07:00
migrate.c mm/thp/migration: switch from flush_tlb_range to flush_pmd_tlb_range 2016-03-17 15:09:34 -07:00
mincore.c thp: change pmd_trans_huge_lock() interface to return ptl 2016-01-21 17:20:51 -08:00
mlock.c mm: fix mlock accouting 2016-01-21 17:20:51 -08:00
mm_init.c mm: meminit: remove mminit_verify_page_links 2015-06-30 19:44:56 -07:00
mmap.c mm: deduplicate memory overcommitment code 2016-03-17 15:09:34 -07:00
mmu_context.c sched/mm: call finish_arch_post_lock_switch in idle_task_exit and use_mm 2014-02-21 08:50:17 +01:00
mmu_notifier.c mmu-notifier: add clear_young callback 2015-09-10 13:29:01 -07:00
mmzone.c mm/mmzone.c: memmap_valid_within() can be boolean 2016-01-14 16:00:49 -08:00
mprotect.c mm, dax: check for pmd_none() after split_huge_pmd() 2016-02-11 18:35:48 -08:00
mremap.c mm: cleanup *pte_alloc* interfaces 2016-03-17 15:09:34 -07:00
msync.c mm/msync: use offset_in_page macro 2015-11-05 19:34:48 -08:00
nobootmem.c x86/mm: Introduce max_possible_pfn 2015-12-06 12:46:31 +01:00
nommu.c mm: deduplicate memory overcommitment code 2016-03-17 15:09:34 -07:00
oom_kill.c mm: oom_kill: don't ignore oom score on exiting tasks 2016-03-17 15:09:34 -07:00
page_alloc.c mm: scale kswapd watermarks in proportion to memory 2016-03-17 15:09:34 -07:00
page_counter.c mm: page_counter: let page_counter_try_charge() return bool 2015-11-05 19:34:48 -08:00
page_ext.c mm/page_poisoning.c: allow for zero poisoning 2016-03-15 16:55:16 -07:00
page_idle.c mm: add page_check_address_transhuge() helper 2016-01-15 17:56:32 -08:00
page_io.c fs: use helper bio_add_page() instead of open coding on bi_io_vec 2015-08-13 12:32:00 -06:00
page_isolation.c mm/page_isolation: do some cleanup in "undo_isolate_page_range" 2016-01-15 17:56:32 -08:00
page_owner.c mm, page_owner: dump page owner info from dump_page() 2016-03-15 16:55:16 -07:00
page_poison.c mm/page_poisoning.c: allow for zero poisoning 2016-03-15 16:55:16 -07:00
page-writeback.c mm: remove unnecessary uses of lock_page_memcg() 2016-03-15 16:55:16 -07:00
pagewalk.c thp: rename split_huge_page_pmd() to split_huge_pmd() 2016-01-15 17:56:32 -08:00
percpu-km.c percpu: implmeent pcpu_nr_empty_pop_pages and chunk->nr_populated 2014-09-02 14:46:05 -04:00
percpu-vm.c percpu: move region iterations out of pcpu_[de]populate_chunk() 2014-09-02 14:46:02 -04:00
percpu.c tree wide: use kvfree() than conditional kfree()/vfree() 2016-01-22 17:02:18 -08:00
pgtable-generic.c mm/thp/migration: switch from flush_tlb_range to flush_pmd_tlb_range 2016-03-17 15:09:34 -07:00
process_vm_access.c ptrace: use fsuid, fsgid, effective creds for fs access checks 2016-01-20 17:09:18 -08:00
quicklist.c mm: delete various needless include <linux/module.h> 2011-10-31 09:20:11 -04:00
readahead.c mm: move lru_to_page to mm_inline.h 2016-01-14 16:00:49 -08:00
rmap.c mm: simplify lock_page_memcg() 2016-03-15 16:55:16 -07:00
shmem.c mm: migrate: do not touch page->mem_cgroup of live pages 2016-03-15 16:55:16 -07:00
slab_common.c mm: memcontrol: zap memcg_kmem_online helper 2016-03-17 15:09:34 -07:00
slab.c mm: memcontrol: report slab usage in cgroup2 memory.stat 2016-03-17 15:09:34 -07:00
slab.h mm: memcontrol: report slab usage in cgroup2 memory.stat 2016-03-17 15:09:34 -07:00
slob.c mm: slab: free kmem_cache_node after destroy sysfs file 2016-02-18 16:23:24 -08:00
slub.c mm/slub: query dynamic DEBUG_PAGEALLOC setting 2016-03-17 15:09:34 -07:00
sparse-vmemmap.c x86, mm: introduce vmem_altmap to augment vmemmap_populate() 2016-01-15 17:56:32 -08:00
sparse.c x86, mm: introduce vmem_altmap to augment vmemmap_populate() 2016-01-15 17:56:32 -08:00
swap_cgroup.c mm: page_cgroup: rename file to mm/swap_cgroup.c 2014-12-10 17:41:09 -08:00
swap_state.c mm: memcontrol: charge swap to cgroup2 2016-01-20 17:09:18 -08:00
swap.c mm, x86: get_user_pages() for dax mappings 2016-01-15 17:56:32 -08:00
swapfile.c wrappers for ->i_mutex access 2016-01-22 18:04:28 -05:00
truncate.c mm: remove unnecessary uses of lock_page_memcg() 2016-03-15 16:55:16 -07:00
userfaultfd.c mm: cleanup *pte_alloc* interfaces 2016-03-17 15:09:34 -07:00
util.c mm: deduplicate memory overcommitment code 2016-03-17 15:09:34 -07:00
vmacache.c mm/vmacache: inline vmacache_valid_mm() 2015-11-05 19:34:48 -08:00
vmalloc.c mm/vmalloc: query dynamic DEBUG_PAGEALLOC setting 2016-03-17 15:09:34 -07:00
vmpressure.c mm/vmpressure.c: fix subtree pressure detection 2016-02-03 08:28:43 -08:00
vmscan.c mm: vmscan: pass root_mem_cgroup instead of NULL to memcg aware shrinker 2016-03-17 15:09:34 -07:00
vmstat.c thp, vmstats: count deferred split events 2016-03-17 15:09:34 -07:00
workingset.c mm: workingset: make shadow node shrinker memcg aware 2016-03-17 15:09:34 -07:00
zbud.c mm/zbud.c: use list_last_entry() instead of list_tail_entry() 2016-01-15 11:40:52 -08:00
zpool.c mm: zsmalloc: constify struct zs_pool name 2015-11-06 17:50:42 -08:00
zsmalloc.c zsmalloc: fix migrate_zspage-zs_free race condition 2016-01-20 17:09:18 -08:00
zswap.c mm/zswap: change incorrect strncmp use to strcmp 2015-12-18 14:25:40 -08:00