linux/mm
Theodore Ts'o 0ae45f63d4 vfs: add support for a lazytime mount option
Add a new mount option which enables a new "lazytime" mode.  This mode
causes atime, mtime, and ctime updates to only be made to the
in-memory version of the inode.  The on-disk times will only get
updated when (a) if the inode needs to be updated for some non-time
related change, (b) if userspace calls fsync(), syncfs() or sync(), or
(c) just before an undeleted inode is evicted from memory.

This is OK according to POSIX because there are no guarantees after a
crash unless userspace explicitly requests via a fsync(2) call.

For workloads which feature a large number of random write to a
preallocated file, the lazytime mount option significantly reduces
writes to the inode table.  The repeated 4k writes to a single block
will result in undesirable stress on flash devices and SMR disk
drives.  Even on conventional HDD's, the repeated writes to the inode
table block will trigger Adjacent Track Interference (ATI) remediation
latencies, which very negatively impact long tail latencies --- which
is a very big deal for web serving tiers (for example).

Google-Bug-Id: 18297052

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-02-05 02:45:00 -05:00
..
backing-dev.c vfs: add support for a lazytime mount option 2015-02-05 02:45:00 -05:00
balloon_compaction.c mm/balloon_compaction: fix deflation when compaction is disabled 2014-10-29 16:33:15 -07:00
bootmem.c mem-hotplug: reset node managed pages when hot-adding a new pgdat 2014-11-13 16:17:06 -08:00
cleancache.c mm: dump page when hitting a VM_BUG_ON using VM_BUG_ON_PAGE 2014-01-23 16:36:50 -08:00
cma.c mm: cma: split cma-reserved in dmesg log 2014-12-18 19:08:10 -08:00
compaction.c mm, compaction: more focused lru and pcplists draining 2014-12-10 17:41:06 -08:00
debug-pagealloc.c mm/debug-pagealloc: make debug-pagealloc boottime configurable 2014-12-13 12:42:48 -08:00
debug.c mm: move page->mem_cgroup bad page handling into generic code 2014-12-10 17:41:09 -08:00
dmapool.c mm/dmapool.c: fixed a brace coding style issue 2014-10-09 22:26:00 -04:00
early_ioremap.c mm: create generic early_ioremap() support 2014-04-07 16:36:15 -07:00
fadvise.c mm: fadvise: document the fadvise(FADV_DONTNEED) behaviour for partial pages 2014-12-13 12:42:49 -08:00
failslab.c
filemap_xip.c mm/xip: share the i_mmap_rwsem 2014-12-13 12:42:45 -08:00
filemap.c mm: get rid of radix tree gfp mask for pagecache_get_page 2014-12-29 12:45:45 -08:00
fremap.c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2014-12-15 15:52:01 -08:00
frontswap.c mm/frontswap.c: fix the condition in BUG_ON 2014-12-10 17:41:08 -08:00
gup.c vm: add VM_FAULT_SIGSEGV handling support 2015-01-29 10:51:32 -08:00
highmem.c mm/highmem: make kmap cache coloring aware 2014-08-06 18:01:22 -07:00
huge_memory.c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2014-12-15 15:52:01 -08:00
hugetlb_cgroup.c mm: hugetlb_cgroup: convert to lockless page counters 2014-12-10 17:41:04 -08:00
hugetlb.c Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2014-12-15 15:52:01 -08:00
hwpoison-inject.c mm/hwpoison-inject.c: remove unnecessary null test before debugfs_remove_recursive 2014-08-06 18:01:19 -07:00
init-mm.c
internal.h mm, compaction: always update cached scanner positions 2014-12-10 17:41:06 -08:00
interval_tree.c mm: convert a few VM_BUG_ON callers to VM_BUG_ON_VMA 2014-10-09 22:25:57 -04:00
iov_iter.c copy_from_iter_nocache() 2014-12-08 20:25:23 -05:00
Kconfig mm/balloon_compaction: add vmstat counters and kpageflags bit 2014-10-09 22:26:01 -04:00
Kconfig.debug mm/debug_pagealloc: remove obsolete Kconfig options 2015-01-08 15:10:52 -08:00
kmemcheck.c mm/slab_common: move kmem_cache definition to internal header 2014-10-09 22:25:50 -04:00
kmemleak-test.c mm/kmemleak-test.c: use pr_fmt for logging 2014-06-06 16:08:18 -07:00
kmemleak.c mm: introduce kmemleak_update_trace() 2014-06-06 16:08:17 -07:00
ksm.c vm: add VM_FAULT_SIGSEGV handling support 2015-01-29 10:51:32 -08:00
list_lru.c mm: keep page cache radix tree nodes in check 2014-04-03 16:21:01 -07:00
maccess.c
madvise.c VFS: Rename do_fallocate() to vfs_fallocate() 2014-11-07 16:17:44 -05:00
Makefile mm/page_owner: keep track of page owners 2014-12-13 12:42:48 -08:00
memblock.c mm/memblock.c: refactor functions to set/clear MEMBLOCK_HOTPLUG 2014-12-13 12:42:46 -08:00
memcontrol.c memcg: remove extra newlines from memcg oom kill log 2015-01-26 13:37:18 -08:00
memory_hotplug.c mm, memory_hotplug/failure: drain single zone pcplists 2014-12-10 17:41:05 -08:00
memory-failure.c mm: vmscan: invoke slab shrinkers from shrink_zone() 2014-12-13 12:42:48 -08:00
memory.c vm: make stack guard page errors return VM_FAULT_SIGSEGV rather than SIGBUS 2015-01-29 11:15:17 -08:00
mempolicy.c Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2014-12-19 18:19:19 -08:00
mempool.c mm/mempool.c: update the kmemleak stack trace for mempool allocations 2014-06-06 16:08:17 -07:00
migrate.c vm_area_operations: kill ->migrate() 2014-12-17 08:26:51 -05:00
mincore.c mm: mincore: add hwpoison page handle 2014-12-13 12:42:46 -08:00
mlock.c Merge branch 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2014-10-13 15:44:12 +02:00
mm_init.c mm: bring back /sys/kernel/mm 2014-01-27 21:02:39 -08:00
mmap.c mm: fix corner case in anon_vma endless growing prevention 2015-01-11 11:45:10 -08:00
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 the callback for mmu_notifier_invalidate_range() 2014-11-13 13:46:09 +11:00
mmzone.c mm: numa: Change page last {nid,pid} into {cpu,pid} 2013-10-09 14:47:45 +02:00
mprotect.c mm: softdirty: enable write notifications on VMAs after VM_SOFTDIRTY cleared 2014-10-14 02:18:28 +02:00
mremap.c Merge git://git.kvack.org/~bcrl/aio-next 2014-12-14 13:36:57 -08:00
msync.c msync: fix incorrect fstart calculation 2014-07-03 09:21:53 -07:00
nobootmem.c mem-hotplug: reset node managed pages when hot-adding a new pgdat 2014-11-13 16:17:06 -08:00
nommu.c mm/nommu: use alloc_pages_exact() rather than its own implementation 2014-12-13 12:42:48 -08:00
oom_kill.c oom: kill the insufficient and no longer needed PT_TRACE_EXIT check 2014-12-13 12:42:49 -08:00
page_alloc.c mm: page_alloc: embed OOM killing naturally into allocation slowpath 2015-01-26 13:37:18 -08:00
page_counter.c mm: memcontrol: remove obsolete kmemcg pinning tricks 2014-12-10 17:41:05 -08:00
page_ext.c mm/page_owner: keep track of page owners 2014-12-13 12:42:48 -08:00
page_io.c fix __swap_writepage() compile failure on old gcc versions 2014-06-14 19:30:48 -05:00
page_isolation.c mm, page_isolation: drain single zone pcplists 2014-12-10 17:41:05 -08:00
page_owner.c mm/page_owner: correct owner information for early allocated pages 2014-12-13 12:42:48 -08:00
page-writeback.c mm: protect set_page_dirty() from ongoing truncation 2015-01-08 15:10:51 -08:00
pagewalk.c mm: use VM_BUG_ON_MM where possible 2014-10-09 22:25:58 -04:00
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 percpu: off by one in BUG_ON() 2014-10-29 10:34:34 -04:00
pgtable-generic.c mm: actually clear pmd_numa before invalidating 2014-08-29 16:28:15 -07:00
process_vm_access.c start adding the tag to iov_iter 2014-05-06 17:32:49 -04:00
quicklist.c
readahead.c mm/readahead.c: remove unused file_ra_state from count_history_pages 2014-08-06 18:01:15 -07:00
rmap.c mm: prevent endless growth of anon_vma hierarchy 2015-01-08 15:10:51 -08:00
shmem.c new helper: iter_is_iovec() 2014-12-17 06:43:56 -05:00
slab_common.c memcg: use generic slab iterators for showing slabinfo 2014-12-10 17:41:07 -08:00
slab.c slab: fix cpuset check in fallback_alloc 2014-12-13 12:42:53 -08:00
slab.h memcg: use generic slab iterators for showing slabinfo 2014-12-10 17:41:07 -08:00
slob.c mm/sl[ao]b: always track caller in kmalloc_(node_)track_caller() 2014-10-09 22:25:50 -04:00
slub.c slub: fix cpuset check in get_any_partial 2014-12-13 12:42:53 -08:00
sparse-vmemmap.c mm/sparse: use memblock apis for early memory allocations 2014-01-21 16:19:47 -08:00
sparse.c mm: use macros from compiler.h instead of __attribute__((...)) 2014-04-07 16:35:54 -07:00
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: page_cgroup: rename file to mm/swap_cgroup.c 2014-12-10 17:41:09 -08:00
swap.c mm: memcontrol: do not kill uncharge batching in free_pages_and_swap_cache 2014-10-09 22:25:59 -04:00
swapfile.c mm: page_cgroup: rename file to mm/swap_cgroup.c 2014-12-10 17:41:09 -08:00
truncate.c mm: Fix comment before truncate_setsize() 2014-11-07 08:29:25 +11:00
util.c proc/maps: make vm_is_stack() logic namespace-friendly 2014-10-09 22:25:50 -04:00
vmacache.c mm,vmacache: count number of system-wide flushes 2014-12-13 12:42:48 -08:00
vmalloc.c mm/vmalloc.c: fix memory ordering bug 2014-12-13 12:42:49 -08:00
vmpressure.c mm/vmpressure.c: fix race in vmpressure_work_fn() 2014-12-02 17:32:07 -08:00
vmscan.c mm/vmscan: fix highidx argument type 2015-01-26 13:37:18 -08:00
vmstat.c mm,vmacache: count number of system-wide flushes 2014-12-13 12:42:48 -08:00
workingset.c mm: keep page cache radix tree nodes in check 2014-04-03 16:21:01 -07:00
zbud.c mm/zbud: init user ops only when it is needed 2014-12-13 12:42:51 -08:00
zpool.c mm/zpool: use prefixed module loading 2014-08-29 16:28:16 -07:00
zsmalloc.c mm/zsmalloc: adjust order of functions 2014-12-18 19:08:11 -08:00
zswap.c mm/zswap: delete unnecessary check before calling free_percpu() 2014-12-13 12:42:50 -08:00