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authorLinus Torvalds <torvalds@linux-foundation.org>2014-01-21 19:05:45 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2014-01-21 19:05:45 -0800
commitdf32e43a54d04eda35d2859beaf90e3864d53288 (patch)
tree7a61cf658b2949bd426285eb9902be7758ced1ba /Documentation
parentfbd918a2026d0464ce9c23f57b7de4bcfccdc2e6 (diff)
parent78d5506e82b21a1a1de68c24182db2c2fe521422 (diff)
Merge branch 'akpm' (incoming from Andrew)
Merge first patch-bomb from Andrew Morton: - a couple of misc things - inotify/fsnotify work from Jan - ocfs2 updates (partial) - about half of MM * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (117 commits) mm/migrate: remove unused function, fail_migrate_page() mm/migrate: remove putback_lru_pages, fix comment on putback_movable_pages mm/migrate: correct failure handling if !hugepage_migration_support() mm/migrate: add comment about permanent failure path mm, page_alloc: warn for non-blockable __GFP_NOFAIL allocation failure mm: compaction: reset scanner positions immediately when they meet mm: compaction: do not mark unmovable pageblocks as skipped in async compaction mm: compaction: detect when scanners meet in isolate_freepages mm: compaction: reset cached scanner pfn's before reading them mm: compaction: encapsulate defer reset logic mm: compaction: trace compaction begin and end memcg, oom: lock mem_cgroup_print_oom_info sched: add tracepoints related to NUMA task migration mm: numa: do not automatically migrate KSM pages mm: numa: trace tasks that fail migration due to rate limiting mm: numa: limit scope of lock for NUMA migrate rate limiting mm: numa: make NUMA-migrate related functions static lib/show_mem.c: show num_poisoned_pages when oom mm/hwpoison: add '#' to hwpoison_inject mm/memblock: use WARN_ONCE when MAX_NUMNODES passed as input parameter ...
Diffstat (limited to 'Documentation')
-rw-r--r--Documentation/filesystems/proc.txt9
-rw-r--r--Documentation/sysctl/vm.txt12
-rw-r--r--Documentation/vm/overcommit-accounting7
3 files changed, 25 insertions, 3 deletions
diff --git a/Documentation/filesystems/proc.txt b/Documentation/filesystems/proc.txt
index 22d89aa37218..8533f5f9bb2d 100644
--- a/Documentation/filesystems/proc.txt
+++ b/Documentation/filesystems/proc.txt
@@ -767,6 +767,7 @@ The "Locked" indicates whether the mapping is locked in memory or not.
MemTotal: 16344972 kB
MemFree: 13634064 kB
+MemAvailable: 14836172 kB
Buffers: 3656 kB
Cached: 1195708 kB
SwapCached: 0 kB
@@ -799,6 +800,14 @@ AnonHugePages: 49152 kB
MemTotal: Total usable ram (i.e. physical ram minus a few reserved
bits and the kernel binary code)
MemFree: The sum of LowFree+HighFree
+MemAvailable: An estimate of how much memory is available for starting new
+ applications, without swapping. Calculated from MemFree,
+ SReclaimable, the size of the file LRU lists, and the low
+ watermarks in each zone.
+ The estimate takes into account that the system needs some
+ page cache to function well, and that not all reclaimable
+ slab will be reclaimable, due to items being in use. The
+ impact of those factors will vary from system to system.
Buffers: Relatively temporary storage for raw disk blocks
shouldn't get tremendously large (20MB or so)
Cached: in-memory cache for files read from the disk (the
diff --git a/Documentation/sysctl/vm.txt b/Documentation/sysctl/vm.txt
index 1fbd4eb7b64a..9f5481bdc5a4 100644
--- a/Documentation/sysctl/vm.txt
+++ b/Documentation/sysctl/vm.txt
@@ -47,6 +47,7 @@ Currently, these files are in /proc/sys/vm:
- numa_zonelist_order
- oom_dump_tasks
- oom_kill_allocating_task
+- overcommit_kbytes
- overcommit_memory
- overcommit_ratio
- page-cluster
@@ -574,6 +575,17 @@ The default value is 0.
==============================================================
+overcommit_kbytes:
+
+When overcommit_memory is set to 2, the committed address space is not
+permitted to exceed swap plus this amount of physical RAM. See below.
+
+Note: overcommit_kbytes is the counterpart of overcommit_ratio. Only one
+of them may be specified at a time. Setting one disables the other (which
+then appears as 0 when read).
+
+==============================================================
+
overcommit_memory:
This value contains a flag that enables memory overcommitment.
diff --git a/Documentation/vm/overcommit-accounting b/Documentation/vm/overcommit-accounting
index 8eaa2fc4b8fa..cbfaaa674118 100644
--- a/Documentation/vm/overcommit-accounting
+++ b/Documentation/vm/overcommit-accounting
@@ -14,8 +14,8 @@ The Linux kernel supports the following overcommit handling modes
2 - Don't overcommit. The total address space commit
for the system is not permitted to exceed swap + a
- configurable percentage (default is 50) of physical RAM.
- Depending on the percentage you use, in most situations
+ configurable amount (default is 50%) of physical RAM.
+ Depending on the amount you use, in most situations
this means a process will not be killed while accessing
pages but will receive errors on memory allocation as
appropriate.
@@ -26,7 +26,8 @@ The Linux kernel supports the following overcommit handling modes
The overcommit policy is set via the sysctl `vm.overcommit_memory'.
-The overcommit percentage is set via `vm.overcommit_ratio'.
+The overcommit amount can be set via `vm.overcommit_ratio' (percentage)
+or `vm.overcommit_kbytes' (absolute value).
The current overcommit limit and amount committed are viewable in
/proc/meminfo as CommitLimit and Committed_AS respectively.