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diff --git a/Documentation/admin-guide/cgroup-v1/memory.rst b/Documentation/admin-guide/cgroup-v1/memory.rst
index 0ae4f564c2d6..fabaad3fd9c2 100644
--- a/Documentation/admin-guide/cgroup-v1/memory.rst
+++ b/Documentation/admin-guide/cgroup-v1/memory.rst
@@ -2,18 +2,18 @@
Memory Resource Controller
==========================
-NOTE:
+.. caution::
This document is hopelessly outdated and it asks for a complete
rewrite. It still contains a useful information so we are keeping it
here but make sure to check the current code if you need a deeper
understanding.
-NOTE:
+.. note::
The Memory Resource Controller has generically been referred to as the
memory controller in this document. Do not confuse memory controller
used here with the memory controller that is used in hardware.
-(For editors) In this document:
+.. hint::
When we mention a cgroup (cgroupfs's directory) with memory controller,
we call it "memory cgroup". When you see git-log and source code, you'll
see patch's title and function names tend to use "memcg".
@@ -23,7 +23,7 @@ Benefits and Purpose of the memory controller
=============================================
The memory controller isolates the memory behaviour of a group of tasks
-from the rest of the system. The article on LWN [12] mentions some probable
+from the rest of the system. The article on LWN [12]_ mentions some probable
uses of the memory controller. The memory controller can be used to
a. Isolate an application or a group of applications
@@ -55,7 +55,8 @@ Features:
- Root cgroup has no limit controls.
Kernel memory support is a work in progress, and the current version provides
- basically functionality. (See Section 2.7)
+ basically functionality. (See :ref:`section 2.7
+ <cgroup-v1-memory-kernel-extension>`)
Brief summary of control files.
@@ -64,6 +65,7 @@ Brief summary of control files.
threads
cgroup.procs show list of processes
cgroup.event_control an interface for event_fd()
+ This knob is not available on CONFIG_PREEMPT_RT systems.
memory.usage_in_bytes show current usage for memory
(See 5.5 for details)
memory.memsw.usage_in_bytes show current usage for memory+Swap
@@ -75,20 +77,23 @@ Brief summary of control files.
memory.max_usage_in_bytes show max memory usage recorded
memory.memsw.max_usage_in_bytes show max memory+Swap usage recorded
memory.soft_limit_in_bytes set/show soft limit of memory usage
+ This knob is not available on CONFIG_PREEMPT_RT systems.
memory.stat show various statistics
memory.use_hierarchy set/show hierarchical account enabled
+ This knob is deprecated and shouldn't be
+ used.
memory.force_empty trigger forced page reclaim
memory.pressure_level set memory pressure notifications
memory.swappiness set/show swappiness parameter of vmscan
(See sysctl's vm.swappiness)
memory.move_charge_at_immigrate set/show controls of moving charges
+ This knob is deprecated and shouldn't be
+ used.
memory.oom_control set/show oom controls.
memory.numa_stat show the number of memory usage per numa
node
- memory.kmem.limit_in_bytes set/show hard limit for kernel memory
- This knob is deprecated and shouldn't be
- used. It is planned that this be removed in
- the foreseeable future.
+ memory.kmem.limit_in_bytes This knob is deprecated and writing to
+ it will return -ENOTSUPP.
memory.kmem.usage_in_bytes show current kernel memory allocation
memory.kmem.failcnt show the number of kernel memory usage
hits limits
@@ -105,16 +110,16 @@ Brief summary of control files.
==========
The memory controller has a long history. A request for comments for the memory
-controller was posted by Balbir Singh [1]. At the time the RFC was posted
+controller was posted by Balbir Singh [1]_. At the time the RFC was posted
there were several implementations for memory control. The goal of the
RFC was to build consensus and agreement for the minimal features required
-for memory control. The first RSS controller was posted by Balbir Singh[2]
-in Feb 2007. Pavel Emelianov [3][4][5] has since posted three versions of the
-RSS controller. At OLS, at the resource management BoF, everyone suggested
-that we handle both page cache and RSS together. Another request was raised
-to allow user space handling of OOM. The current memory controller is
+for memory control. The first RSS controller was posted by Balbir Singh [2]_
+in Feb 2007. Pavel Emelianov [3]_ [4]_ [5]_ has since posted three versions
+of the RSS controller. At OLS, at the resource management BoF, everyone
+suggested that we handle both page cache and RSS together. Another request was
+raised to allow user space handling of OOM. The current memory controller is
at version 6; it combines both mapped (RSS) and unmapped Page
-Cache Control [11].
+Cache Control [11]_.
2. Memory Control
=================
@@ -145,7 +150,8 @@ specific data structure (mem_cgroup) associated with it.
2.2. Accounting
---------------
-::
+.. code-block::
+ :caption: Figure 1: Hierarchy of Accounting
+--------------------+
| mem_cgroup |
@@ -165,7 +171,6 @@ specific data structure (mem_cgroup) associated with it.
| | | |
+---------------+ +---------------+
- (Figure 1: Hierarchy of Accounting)
Figure 1 shows the important aspects of the controller
@@ -199,11 +204,11 @@ An RSS page is unaccounted when it's fully unmapped. A PageCache page is
unaccounted when it's removed from radix-tree. Even if RSS pages are fully
unmapped (by kswapd), they may exist as SwapCache in the system until they
are really freed. Such SwapCaches are also accounted.
-A swapped-in page is not accounted until it's mapped.
+A swapped-in page is accounted after adding into swapcache.
Note: The kernel does swapin-readahead and reads multiple swaps at once.
-This means swapped-in pages may contain pages for other tasks than a task
-causing page fault. So, we avoid accounting at swap-in I/O.
+Since page's memcg recorded into swap whatever memsw enabled, the page will
+be accounted after swapin.
At page migration, accounting information is kept.
@@ -219,21 +224,17 @@ behind this approach is that a cgroup that aggressively uses a shared
page will eventually get charged for it (once it is uncharged from
the cgroup that brought it in -- this will happen on memory pressure).
-But see section 8.2: when moving a task to another cgroup, its pages may
-be recharged to the new cgroup, if move_charge_at_immigrate has been chosen.
-
-Exception: If CONFIG_MEMCG_SWAP is not used.
-When you do swapoff and make swapped-out pages of shmem(tmpfs) to
-be backed into memory in force, charges for pages are accounted against the
-caller of swapoff rather than the users of shmem.
+But see :ref:`section 8.2 <cgroup-v1-memory-movable-charges>` when moving a
+task to another cgroup, its pages may be recharged to the new cgroup, if
+move_charge_at_immigrate has been chosen.
-2.4 Swap Extension (CONFIG_MEMCG_SWAP)
+2.4 Swap Extension
--------------------------------------
-Swap Extension allows you to record charge for swap. A swapped-in page is
-charged back to original page allocator if possible.
+Swap usage is always recorded for each of cgroup. Swap Extension allows you to
+read and limit it.
-When swap is accounted, following files are added.
+When CONFIG_SWAP is enabled, following files are added.
- memory.memsw.usage_in_bytes.
- memory.memsw.limit_in_bytes.
@@ -247,7 +248,8 @@ In this case, setting memsw.limit_in_bytes=3G will prevent bad use of swap.
By using the memsw limit, you can avoid system OOM which can be caused by swap
shortage.
-**why 'memory+swap' rather than swap**
+2.4.1 why 'memory+swap' rather than swap
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
The global LRU(kswapd) can swap out arbitrary pages. Swap-out means
to move account from memory to swap...there is no change in usage of
@@ -255,7 +257,8 @@ memory+swap. In other words, when we want to limit the usage of swap without
affecting global LRU, memory+swap limit is better than just limiting swap from
an OS point of view.
-**What happens when a cgroup hits memory.memsw.limit_in_bytes**
+2.4.2. What happens when a cgroup hits memory.memsw.limit_in_bytes
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
When a cgroup hits memory.memsw.limit_in_bytes, it's useless to do swap-out
in this cgroup. Then, swap-out will not be done by cgroup routine and file
@@ -271,41 +274,40 @@ global VM. When a cgroup goes over its limit, we first try
to reclaim memory from the cgroup so as to make space for the new
pages that the cgroup has touched. If the reclaim is unsuccessful,
an OOM routine is invoked to select and kill the bulkiest task in the
-cgroup. (See 10. OOM Control below.)
+cgroup. (See :ref:`10. OOM Control <cgroup-v1-memory-oom-control>` below.)
The reclaim algorithm has not been modified for cgroups, except that
pages that are selected for reclaiming come from the per-cgroup LRU
list.
-NOTE:
- Reclaim does not work for the root cgroup, since we cannot set any
- limits on the root cgroup.
+.. note::
+ Reclaim does not work for the root cgroup, since we cannot set any
+ limits on the root cgroup.
-Note2:
- When panic_on_oom is set to "2", the whole system will panic.
+.. note::
+ When panic_on_oom is set to "2", the whole system will panic.
When oom event notifier is registered, event will be delivered.
-(See oom_control section)
+(See :ref:`oom_control <cgroup-v1-memory-oom-control>` section)
2.6 Locking
-----------
- lock_page_cgroup()/unlock_page_cgroup() should not be called under
- the i_pages lock.
+Lock order is as follows::
- Other lock order is following:
+ Page lock (PG_locked bit of page->flags)
+ mm->page_table_lock or split pte_lock
+ folio_memcg_lock (memcg->move_lock)
+ mapping->i_pages lock
+ lruvec->lru_lock.
- PG_locked.
- mm->page_table_lock
- pgdat->lru_lock
- lock_page_cgroup.
+Per-node-per-memcgroup LRU (cgroup's private LRU) is guarded by
+lruvec->lru_lock; PG_lru bit of page->flags is cleared before
+isolating a page from its LRU under lruvec->lru_lock.
- In many cases, just lock_page_cgroup() is called.
+.. _cgroup-v1-memory-kernel-extension:
- per-zone-per-cgroup LRU (cgroup's private LRU) is just guarded by
- pgdat->lru_lock, it has no lock of its own.
-
-2.7 Kernel Memory Extension (CONFIG_MEMCG_KMEM)
+2.7 Kernel Memory Extension
-----------------------------------------------
With the Kernel memory extension, the Memory Controller is able to limit
@@ -366,17 +368,17 @@ U != 0, K = unlimited:
U != 0, K < U:
Kernel memory is a subset of the user memory. This setup is useful in
- deployments where the total amount of memory per-cgroup is overcommited.
- Overcommiting kernel memory limits is definitely not recommended, since the
+ deployments where the total amount of memory per-cgroup is overcommitted.
+ Overcommitting kernel memory limits is definitely not recommended, since the
box can still run out of non-reclaimable memory.
In this case, the admin could set up K so that the sum of all groups is
never greater than the total memory, and freely set U at the cost of his
QoS.
-WARNING:
- In the current implementation, memory reclaim will NOT be
- triggered for a cgroup when it hits K while staying below U, which makes
- this setup impractical.
+ .. warning::
+ In the current implementation, memory reclaim will NOT be triggered for
+ a cgroup when it hits K while staying below U, which makes this setup
+ impractical.
U != 0, K >= U:
Since kmem charges will also be fed to the user counter and reclaim will be
@@ -387,47 +389,41 @@ U != 0, K >= U:
3. User Interface
=================
-3.0. Configuration
-------------------
-
-a. Enable CONFIG_CGROUPS
-b. Enable CONFIG_MEMCG
-c. Enable CONFIG_MEMCG_SWAP (to use swap extension)
-d. Enable CONFIG_MEMCG_KMEM (to use kmem extension)
-
-3.1. Prepare the cgroups (see cgroups.txt, Why are cgroups needed?)
--------------------------------------------------------------------
+To use the user interface:
-::
+1. Enable CONFIG_CGROUPS and CONFIG_MEMCG options
+2. Prepare the cgroups (see :ref:`Why are cgroups needed?
+ <cgroups-why-needed>` for the background information)::
# mount -t tmpfs none /sys/fs/cgroup
# mkdir /sys/fs/cgroup/memory
# mount -t cgroup none /sys/fs/cgroup/memory -o memory
-3.2. Make the new group and move bash into it::
+3. Make the new group and move bash into it::
# mkdir /sys/fs/cgroup/memory/0
# echo $$ > /sys/fs/cgroup/memory/0/tasks
-Since now we're in the 0 cgroup, we can alter the memory limit::
+4. Since now we're in the 0 cgroup, we can alter the memory limit::
# echo 4M > /sys/fs/cgroup/memory/0/memory.limit_in_bytes
-NOTE:
- We can use a suffix (k, K, m, M, g or G) to indicate values in kilo,
- mega or gigabytes. (Here, Kilo, Mega, Giga are Kibibytes, Mebibytes,
- Gibibytes.)
+ The limit can now be queried::
-NOTE:
- We can write "-1" to reset the ``*.limit_in_bytes(unlimited)``.
+ # cat /sys/fs/cgroup/memory/0/memory.limit_in_bytes
+ 4194304
-NOTE:
- We cannot set limits on the root cgroup any more.
+.. note::
+ We can use a suffix (k, K, m, M, g or G) to indicate values in kilo,
+ mega or gigabytes. (Here, Kilo, Mega, Giga are Kibibytes, Mebibytes,
+ Gibibytes.)
-::
+.. note::
+ We can write "-1" to reset the ``*.limit_in_bytes(unlimited)``.
+
+.. note::
+ We cannot set limits on the root cgroup any more.
- # cat /sys/fs/cgroup/memory/0/memory.limit_in_bytes
- 4194304
We can check the usage::
@@ -466,6 +462,8 @@ test because it has noise of shared objects/status.
But the above two are testing extreme situations.
Trying usual test under memory controller is always helpful.
+.. _cgroup-v1-memory-test-troubleshoot:
+
4.1 Troubleshooting
-------------------
@@ -478,8 +476,11 @@ terminated by the OOM killer. There are several causes for this:
A sync followed by echo 1 > /proc/sys/vm/drop_caches will help get rid of
some of the pages cached in the cgroup (page cache pages).
-To know what happens, disabling OOM_Kill as per "10. OOM Control" (below) and
-seeing what happens will be helpful.
+To know what happens, disabling OOM_Kill as per :ref:`"10. OOM Control"
+<cgroup-v1-memory-oom-control>` (below) and seeing what happens will be
+helpful.
+
+.. _cgroup-v1-memory-test-task-migration:
4.2 Task migration
------------------
@@ -490,26 +491,24 @@ remain charged to it, the charge is dropped when the page is freed or
reclaimed.
You can move charges of a task along with task migration.
-See 8. "Move charges at task migration"
+See :ref:`8. "Move charges at task migration" <cgroup-v1-memory-move-charges>`
4.3 Removing a cgroup
---------------------
-A cgroup can be removed by rmdir, but as discussed in sections 4.1 and 4.2, a
-cgroup might have some charge associated with it, even though all
-tasks have migrated away from it. (because we charge against pages, not
-against tasks.)
+A cgroup can be removed by rmdir, but as discussed in :ref:`sections 4.1
+<cgroup-v1-memory-test-troubleshoot>` and :ref:`4.2
+<cgroup-v1-memory-test-task-migration>`, a cgroup might have some charge
+associated with it, even though all tasks have migrated away from it. (because
+we charge against pages, not against tasks.)
-We move the stats to root (if use_hierarchy==0) or parent (if
-use_hierarchy==1), and no change on the charge except uncharging
+We move the stats to parent, and no change on the charge except uncharging
from the child.
Charges recorded in swap information is not updated at removal of cgroup.
Recorded information is discarded and a cgroup which uses swap (swapcache)
will be charged as a new owner of it.
-About use_hierarchy, see Section 6.
-
5. Misc. interfaces
===================
@@ -527,76 +526,69 @@ About use_hierarchy, see Section 6.
charged file caches. Some out-of-use page caches may keep charged until
memory pressure happens. If you want to avoid that, force_empty will be useful.
- Also, note that when memory.kmem.limit_in_bytes is set the charges due to
- kernel pages will still be seen. This is not considered a failure and the
- write will still return success. In this case, it is expected that
- memory.kmem.usage_in_bytes == memory.usage_in_bytes.
-
- About use_hierarchy, see Section 6.
-
5.2 stat file
-------------
-memory.stat file includes following statistics
-
-per-memory cgroup local status
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-=============== ===============================================================
-cache # of bytes of page cache memory.
-rss # of bytes of anonymous and swap cache memory (includes
- transparent hugepages).
-rss_huge # of bytes of anonymous transparent hugepages.
-mapped_file # of bytes of mapped file (includes tmpfs/shmem)
-pgpgin # of charging events to the memory cgroup. The charging
- event happens each time a page is accounted as either mapped
- anon page(RSS) or cache page(Page Cache) to the cgroup.
-pgpgout # of uncharging events to the memory cgroup. The uncharging
- event happens each time a page is unaccounted from the cgroup.
-swap # of bytes of swap usage
-dirty # of bytes that are waiting to get written back to the disk.
-writeback # of bytes of file/anon cache that are queued for syncing to
- disk.
-inactive_anon # of bytes of anonymous and swap cache memory on inactive
- LRU list.
-active_anon # of bytes of anonymous and swap cache memory on active
- LRU list.
-inactive_file # of bytes of file-backed memory on inactive LRU list.
-active_file # of bytes of file-backed memory on active LRU list.
-unevictable # of bytes of memory that cannot be reclaimed (mlocked etc).
-=============== ===============================================================
-
-status considering hierarchy (see memory.use_hierarchy settings)
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-========================= ===================================================
-hierarchical_memory_limit # of bytes of memory limit with regard to hierarchy
- under which the memory cgroup is
-hierarchical_memsw_limit # of bytes of memory+swap limit with regard to
- hierarchy under which memory cgroup is.
-
-total_<counter> # hierarchical version of <counter>, which in
- addition to the cgroup's own value includes the
- sum of all hierarchical children's values of
- <counter>, i.e. total_cache
-========================= ===================================================
-
-The following additional stats are dependent on CONFIG_DEBUG_VM
-^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-
-========================= ========================================
-recent_rotated_anon VM internal parameter. (see mm/vmscan.c)
-recent_rotated_file VM internal parameter. (see mm/vmscan.c)
-recent_scanned_anon VM internal parameter. (see mm/vmscan.c)
-recent_scanned_file VM internal parameter. (see mm/vmscan.c)
-========================= ========================================
-
-Memo:
+memory.stat file includes following statistics:
+
+ * per-memory cgroup local status
+
+ =============== ===============================================================
+ cache # of bytes of page cache memory.
+ rss # of bytes of anonymous and swap cache memory (includes
+ transparent hugepages).
+ rss_huge # of bytes of anonymous transparent hugepages.
+ mapped_file # of bytes of mapped file (includes tmpfs/shmem)
+ pgpgin # of charging events to the memory cgroup. The charging
+ event happens each time a page is accounted as either mapped
+ anon page(RSS) or cache page(Page Cache) to the cgroup.
+ pgpgout # of uncharging events to the memory cgroup. The uncharging
+ event happens each time a page is unaccounted from the
+ cgroup.
+ swap # of bytes of swap usage
+ dirty # of bytes that are waiting to get written back to the disk.
+ writeback # of bytes of file/anon cache that are queued for syncing to
+ disk.
+ inactive_anon # of bytes of anonymous and swap cache memory on inactive
+ LRU list.
+ active_anon # of bytes of anonymous and swap cache memory on active
+ LRU list.
+ inactive_file # of bytes of file-backed memory and MADV_FREE anonymous
+ memory (LazyFree pages) on inactive LRU list.
+ active_file # of bytes of file-backed memory on active LRU list.
+ unevictable # of bytes of memory that cannot be reclaimed (mlocked etc).
+ =============== ===============================================================
+
+ * status considering hierarchy (see memory.use_hierarchy settings):
+
+ ========================= ===================================================
+ hierarchical_memory_limit # of bytes of memory limit with regard to
+ hierarchy
+ under which the memory cgroup is
+ hierarchical_memsw_limit # of bytes of memory+swap limit with regard to
+ hierarchy under which memory cgroup is.
+
+ total_<counter> # hierarchical version of <counter>, which in
+ addition to the cgroup's own value includes the
+ sum of all hierarchical children's values of
+ <counter>, i.e. total_cache
+ ========================= ===================================================
+
+ * additional vm parameters (depends on CONFIG_DEBUG_VM):
+
+ ========================= ========================================
+ recent_rotated_anon VM internal parameter. (see mm/vmscan.c)
+ recent_rotated_file VM internal parameter. (see mm/vmscan.c)
+ recent_scanned_anon VM internal parameter. (see mm/vmscan.c)
+ recent_scanned_file VM internal parameter. (see mm/vmscan.c)
+ ========================= ========================================
+
+.. hint::
recent_rotated means recent frequency of LRU rotation.
recent_scanned means recent # of scans to LRU.
showing for better debug please see the code for meanings.
-Note:
+.. note::
Only anonymous and swap cache memory is listed as part of 'rss' stat.
This should not be confused with the true 'resident set size' or the
amount of physical memory used by the cgroup.
@@ -680,31 +672,20 @@ hierarchy::
d e
In the diagram above, with hierarchical accounting enabled, all memory
-usage of e, is accounted to its ancestors up until the root (i.e, c and root),
-that has memory.use_hierarchy enabled. If one of the ancestors goes over its
-limit, the reclaim algorithm reclaims from the tasks in the ancestor and the
-children of the ancestor.
-
-6.1 Enabling hierarchical accounting and reclaim
-------------------------------------------------
+usage of e, is accounted to its ancestors up until the root (i.e, c and root).
+If one of the ancestors goes over its limit, the reclaim algorithm reclaims
+from the tasks in the ancestor and the children of the ancestor.
-A memory cgroup by default disables the hierarchy feature. Support
-can be enabled by writing 1 to memory.use_hierarchy file of the root cgroup::
+6.1 Hierarchical accounting and reclaim
+---------------------------------------
- # echo 1 > memory.use_hierarchy
-
-The feature can be disabled by::
+Hierarchical accounting is enabled by default. Disabling the hierarchical
+accounting is deprecated. An attempt to do it will result in a failure
+and a warning printed to dmesg.
- # echo 0 > memory.use_hierarchy
+For compatibility reasons writing 1 to memory.use_hierarchy will always pass::
-NOTE1:
- Enabling/disabling will fail if either the cgroup already has other
- cgroups created below it, or if the parent cgroup has use_hierarchy
- enabled.
-
-NOTE2:
- When panic_on_oom is set to "2", the whole system will panic in
- case of an OOM event in any cgroup.
+ # echo 1 > memory.use_hierarchy
7. Soft limits
==============
@@ -738,15 +719,25 @@ If we want to change this to 1G, we can at any time use::
# echo 1G > memory.soft_limit_in_bytes
-NOTE1:
+.. note::
Soft limits take effect over a long period of time, since they involve
reclaiming memory for balancing between memory cgroups
-NOTE2:
+
+.. note::
It is recommended to set the soft limit always below the hard limit,
otherwise the hard limit will take precedence.
-8. Move charges at task migration
-=================================
+.. _cgroup-v1-memory-move-charges:
+
+8. Move charges at task migration (DEPRECATED!)
+===============================================
+
+THIS IS DEPRECATED!
+
+It's expensive and unreliable! It's better practice to launch workload
+tasks directly from inside their target cgroup. Use dedicated workload
+cgroups to allow fine-grained policy adjustments without having to
+move physical pages between control domains.
Users can move charges associated with a task along with task migration, that
is, uncharge task's pages from the old cgroup and charge them to the new cgroup.
@@ -763,23 +754,29 @@ If you want to enable it::
# echo (some positive value) > memory.move_charge_at_immigrate
-Note:
+.. note::
Each bits of move_charge_at_immigrate has its own meaning about what type
- of charges should be moved. See 8.2 for details.
-Note:
+ of charges should be moved. See :ref:`section 8.2
+ <cgroup-v1-memory-movable-charges>` for details.
+
+.. note::
Charges are moved only when you move mm->owner, in other words,
a leader of a thread group.
-Note:
+
+.. note::
If we cannot find enough space for the task in the destination cgroup, we
try to make space by reclaiming memory. Task migration may fail if we
cannot make enough space.
-Note:
+
+.. note::
It can take several seconds if you move charges much.
And if you want disable it again::
# echo 0 > memory.move_charge_at_immigrate
+.. _cgroup-v1-memory-movable-charges:
+
8.2 Type of charges which can be moved
--------------------------------------
@@ -829,6 +826,8 @@ threshold in any direction.
It's applicable for root and non-root cgroup.
+.. _cgroup-v1-memory-oom-control:
+
10. OOM Control
===============
@@ -873,6 +872,9 @@ At reading, current status of OOM is shown.
(if 1, oom-killer is disabled)
- under_oom 0 or 1
(if 1, the memory cgroup is under OOM, tasks may be stopped.)
+ - oom_kill integer counter
+ The number of processes belonging to this cgroup killed by any
+ kind of OOM killer.
11. Memory Pressure
===================
@@ -981,25 +983,27 @@ commented and discussed quite extensively in the community.
References
==========
-1. Singh, Balbir. RFC: Memory Controller, http://lwn.net/Articles/206697/
-2. Singh, Balbir. Memory Controller (RSS Control),
+.. [1] Singh, Balbir. RFC: Memory Controller, http://lwn.net/Articles/206697/
+.. [2] Singh, Balbir. Memory Controller (RSS Control),
http://lwn.net/Articles/222762/
-3. Emelianov, Pavel. Resource controllers based on process cgroups
- http://lkml.org/lkml/2007/3/6/198
-4. Emelianov, Pavel. RSS controller based on process cgroups (v2)
- http://lkml.org/lkml/2007/4/9/78
-5. Emelianov, Pavel. RSS controller based on process cgroups (v3)
- http://lkml.org/lkml/2007/5/30/244
+.. [3] Emelianov, Pavel. Resource controllers based on process cgroups
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6. Menage, Paul. Control Groups v10, http://lwn.net/Articles/236032/
7. Vaidyanathan, Srinivasan, Control Groups: Pagecache accounting and control
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