Zlatko Calusic cda73a10eb mm: do not sleep in balance_pgdat if there's no i/o congestion ... On a 4GB RAM machine, where Normal zone is much smaller than DMA32 zone, the Normal zone gets fragmented in time. This requires relatively more pressure in balance_pgdat to get the zone above the required watermark. Unfortunately, the congestion_wait() call in there slows it down for a completely wrong reason, expecting that there's a lot of writeback/swapout, even when there's none (much more common). After a few days, when fragmentation progresses, this flawed logic translates to a very high CPU iowait times, even though there's no I/O congestion at all. If THP is enabled, the problem occurs sooner, but I was able to see it even on !THP kernels, just by giving it a bit more time to occur. The proper way to deal with this is to not wait, unless there's congestion. Thanks to Mel Gorman, we already have the function that perfectly fits the job. The patch was tested on a machine which nicely revealed the problem after only 1 day of uptime, and it's been working great. Signed-off-by: Zlatko Calusic <zlatko.calusic@iskon.hr> Acked-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>		2012-12-20 07:06:56 -08:00
..
backing-dev.c	Revert "bdi: add a user-tunable cpu_list for the bdi flusher threads"	2012-12-17 11:29:09 -08:00
balloon_compaction.c	mm: introduce a common interface for balloon pages mobility	2012-12-11 17:22:26 -08:00
bootmem.c	mm/bootmem.c: remove unused wrapper function reserve_bootmem_generic()	2012-12-12 17:38:35 -08:00
bounce.c	bounce: allow use of bounce pool via config option	2012-07-18 16:40:35 -04:00
cleancache.c	->encode_fh() API change	2012-05-29 23:28:33 -04:00
compaction.c	Automatic NUMA Balancing V11	2012-12-16 15:18:08 -08:00
debug-pagealloc.c	mm, x86: Remove debug_pagealloc_enabled	2011-12-06 09:24:07 +01:00
dmapool.c	dmapool: make DMAPOOL_DEBUG detect corruption of free marker	2012-12-11 17:22:24 -08:00
fadvise.c	switch simple cases of fget_light to fdget	2012-09-26 22:20:08 -04:00
failslab.c	switch debugfs to umode_t	2012-01-03 22:54:56 -05:00
filemap_xip.c	mm: move all mmu notifier invocations to be done outside the PT lock	2012-10-09 16:22:58 +09:00
filemap.c	readahead: fault retry breaks mmap file read random detection	2012-10-09 16:22:47 +09:00
fremap.c	remap_file_pages: correctly handle the case of a NULL vm_ops pointer	2012-10-19 13:37:57 -07:00
frontswap.c	frontswap: support exclusive gets if tmem backend is capable	2012-09-21 10:38:12 -04:00
highmem.c	mm, highmem: get virtual address of the page using PKMAP_ADDR()	2012-12-11 17:22:24 -08:00
huge_memory.c	mm: fix kernel BUG at huge_memory.c:1474!	2012-12-16 19:02:38 -08:00
hugetlb_cgroup.c	mm/hugetlb: create hugetlb cgroup file in hugetlb_init	2012-12-18 15:02:15 -08:00
hugetlb.c	mm/hugetlb: create hugetlb cgroup file in hugetlb_init	2012-12-18 15:02:15 -08:00
hwpoison-inject.c	memcg: rename config variables	2012-07-31 18:42:43 -07:00
init-mm.c	atomic: use <linux/atomic.h>	2011-07-26 16:49:47 -07:00
internal.h	Automatic NUMA Balancing V11	2012-12-16 15:18:08 -08:00
interval_tree.c	mm: add CONFIG_DEBUG_VM_RB build option	2012-10-09 16:22:42 +09:00
Kconfig	memory-hotplug: document and enable CONFIG_MOVABLE_NODE	2012-12-18 15:02:12 -08:00
Kconfig.debug	mm: more intensive memory corruption debugging	2012-01-10 16:30:42 -08:00
kmemcheck.c
kmemleak-test.c	kmemleak: remove memset by using kzalloc	2011-01-27 18:31:51 +00:00
kmemleak.c	mm/kmemleak.c: remove obsolete simple_strtoul	2012-12-18 15:02:15 -08:00
ksm.c	Automatic NUMA Balancing V11	2012-12-16 15:18:08 -08:00
maccess.c	mm: Map most files to use export.h instead of module.h	2011-10-31 09:20:12 -04:00
madvise.c	mm: prepare VM_DONTDUMP for using in drivers	2012-10-09 16:22:18 +09:00
Makefile	mm: introduce a common interface for balloon pages mobility	2012-12-11 17:22:26 -08:00
memblock.c	x86, mm: Trim memory in memblock to be page aligned	2012-10-24 11:52:21 -07:00
memcontrol.c	slab: propagate tunable values	2012-12-18 15:02:14 -08:00
memory_hotplug.c	mm/memory_hotplug.c: improve comments	2012-12-18 15:02:15 -08:00
memory-failure.c	Automatic NUMA Balancing V11	2012-12-16 15:18:08 -08:00
memory.c	mm: use kbasename()	2012-12-17 17:15:17 -08:00
mempolicy.c	Automatic NUMA Balancing V11	2012-12-16 15:18:08 -08:00
mempool.c	mempool: add @gfp_mask to mempool_create_node()	2012-06-25 11:53:47 +02:00
migrate.c	mm,numa: fix update_mmu_cache_pmd call	2012-12-17 19:37:03 -08:00
mincore.c	mm: thp: fix pmd_bad() triggering in code paths holding mmap_sem read mode	2012-03-21 17:54:54 -07:00
mlock.c	mm, thp: fix mlock statistics	2012-10-09 16:23:03 +09:00
mm_init.c	mm: Map most files to use export.h instead of module.h	2011-10-31 09:20:12 -04:00
mmap.c	Automatic NUMA Balancing V11	2012-12-16 15:18:08 -08:00
mmu_context.c	mm, counters: remove task argument to sync_mm_rss() and __sync_task_rss_stat()	2012-03-21 17:54:59 -07:00
mmu_notifier.c	mm/mmu_notifier: allocate mmu_notifier in advance	2012-10-25 14:37:53 -07:00
mmzone.c	memcg: fix hotplugged memory zone oops	2012-11-16 14:33:04 -08:00
mprotect.c	mm/mprotect.c: coding-style cleanups	2012-12-18 15:02:15 -08:00
mremap.c	Automatic NUMA Balancing V11	2012-12-16 15:18:08 -08:00
msync.c
nobootmem.c	mm: introduce new field "managed_pages" to struct zone	2012-12-12 17:38:34 -08:00
nommu.c	mm: export a function to get vm committed memory	2012-11-15 15:41:22 -08:00
oom_kill.c	mm, oom: remove redundant sleep in pagefault oom handler	2012-12-12 17:38:34 -08:00
page_alloc.c	mm: allocate kernel pages to the right memcg	2012-12-18 15:02:12 -08:00
page_cgroup.c	memcontrol: use N_MEMORY instead N_HIGH_MEMORY	2012-12-12 17:38:32 -08:00
page_io.c	mm: add support for direct_IO to highmem pages	2012-07-31 18:42:47 -07:00
page_isolation.c	memory-hotplug: skip HWPoisoned page when offlining pages	2012-12-11 17:22:22 -08:00
page-writeback.c	writeback: remove nr_pages_dirtied arg from balance_dirty_pages_ratelimited_nr()	2012-12-11 17:22:21 -08:00
pagewalk.c	thp: change split_huge_page_pmd() interface	2012-12-12 17:38:31 -08:00
percpu-km.c
percpu-vm.c	mm: fix kernel-doc warnings	2012-06-20 14:39:36 -07:00
percpu.c	mm, percpu: Make sure percpu_alloc early parameter has an argument	2012-12-02 06:23:04 -08:00
pgtable-generic.c	mm: Only flush the TLB when clearing an accessible pte	2012-12-11 14:28:34 +00:00
process_vm_access.c	aio/vfs: cleanup of rw_copy_check_uvector() and compat_rw_copy_check_uvector()	2012-05-31 17:49:32 -07:00
quicklist.c	mm: delete various needless include <linux/module.h>	2011-10-31 09:20:11 -04:00
readahead.c	switch simple cases of fget_light to fdget	2012-09-26 22:20:08 -04:00
rmap.c	Automatic NUMA Balancing V11	2012-12-16 15:18:08 -08:00
shmem.c	lseek: the "whence" argument is called "whence"	2012-12-17 17:15:12 -08:00
slab_common.c	slab: propagate tunable values	2012-12-18 15:02:14 -08:00
slab.c	memcg: add comments clarifying aspects of cache attribute propagation	2012-12-18 15:02:15 -08:00
slab.h	slab: propagate tunable values	2012-12-18 15:02:14 -08:00
slob.c	sl[au]b: always get the cache from its page in kmem_cache_free()	2012-12-18 15:02:14 -08:00
slub.c	slub: drop mutex before deleting sysfs entry	2012-12-18 15:02:15 -08:00
sparse-vmemmap.c	mm: delete various needless include <linux/module.h>	2011-10-31 09:20:11 -04:00
sparse.c	memory-hotplug, mm/sparse.c: clear the memory to store struct page	2012-12-11 17:22:23 -08:00
swap_state.c	mm: add support for a filesystem to activate swap files and use direct_IO for writing swap pages	2012-07-31 18:42:47 -07:00
swap.c	mm: remove vma arg from page_evictable	2012-10-09 16:22:55 +09:00
swapfile.c	mm, oom: fix race when specifying a thread as the oom origin	2012-12-11 17:22:27 -08:00
truncate.c	mm: use clear_page_mlock() in page_remove_rmap()	2012-10-09 16:22:56 +09:00
util.c	Merge branch 'master' into for-next	2012-10-28 19:29:19 +01:00
vmalloc.c	mm: use IS_ENABLED(CONFIG_NUMA) instead of NUMA_BUILD	2012-12-11 17:22:22 -08:00
vmscan.c	mm: do not sleep in balance_pgdat if there's no i/o congestion	2012-12-20 07:06:56 -08:00
vmstat.c	Automatic NUMA Balancing V11	2012-12-16 15:18:08 -08:00