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authorLinus Torvalds <torvalds@linux-foundation.org>2014-12-10 18:34:42 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2014-12-10 18:34:42 -0800
commitb6da0076bab5a12afb19312ffee41c95490af2a0 (patch)
tree52a5675b9c2ff95d88b981d5b9a3822f6073c112 /Documentation/cgroups/memory.txt
parentcbfe0de303a55ed96d8831c2d5f56f8131cd6612 (diff)
parenta53b831549141aa060a8b54b76e3a42870d74cc0 (diff)
downloadlinux-b6da0076bab5a12afb19312ffee41c95490af2a0.tar.bz2
Merge branch 'akpm' (patchbomb from Andrew)
Merge first patchbomb from Andrew Morton: - a few minor cifs fixes - dma-debug upadtes - ocfs2 - slab - about half of MM - procfs - kernel/exit.c - panic.c tweaks - printk upates - lib/ updates - checkpatch updates - fs/binfmt updates - the drivers/rtc tree - nilfs - kmod fixes - more kernel/exit.c - various other misc tweaks and fixes * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (190 commits) exit: pidns: fix/update the comments in zap_pid_ns_processes() exit: pidns: alloc_pid() leaks pid_namespace if child_reaper is exiting exit: exit_notify: re-use "dead" list to autoreap current exit: reparent: call forget_original_parent() under tasklist_lock exit: reparent: avoid find_new_reaper() if no children exit: reparent: introduce find_alive_thread() exit: reparent: introduce find_child_reaper() exit: reparent: document the ->has_child_subreaper checks exit: reparent: s/while_each_thread/for_each_thread/ in find_new_reaper() exit: reparent: fix the cross-namespace PR_SET_CHILD_SUBREAPER reparenting exit: reparent: fix the dead-parent PR_SET_CHILD_SUBREAPER reparenting exit: proc: don't try to flush /proc/tgid/task/tgid exit: release_task: fix the comment about group leader accounting exit: wait: drop tasklist_lock before psig->c* accounting exit: wait: don't use zombie->real_parent exit: wait: cleanup the ptrace_reparented() checks usermodehelper: kill the kmod_thread_locker logic usermodehelper: don't use CLONE_VFORK for ____call_usermodehelper() fs/hfs/catalog.c: fix comparison bug in hfs_cat_keycmp nilfs2: fix the nilfs_iget() vs. nilfs_new_inode() races ...
Diffstat (limited to 'Documentation/cgroups/memory.txt')
-rw-r--r--Documentation/cgroups/memory.txt26
1 files changed, 15 insertions, 11 deletions
diff --git a/Documentation/cgroups/memory.txt b/Documentation/cgroups/memory.txt
index 02ab997a1ed2..46b2b5080317 100644
--- a/Documentation/cgroups/memory.txt
+++ b/Documentation/cgroups/memory.txt
@@ -1,5 +1,10 @@
Memory Resource Controller
+NOTE: 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: 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.
@@ -52,9 +57,9 @@ Brief summary of control files.
tasks # attach a task(thread) and show list of threads
cgroup.procs # show list of processes
cgroup.event_control # an interface for event_fd()
- memory.usage_in_bytes # show current res_counter usage for memory
+ memory.usage_in_bytes # show current usage for memory
(See 5.5 for details)
- memory.memsw.usage_in_bytes # show current res_counter usage for memory+Swap
+ memory.memsw.usage_in_bytes # show current usage for memory+Swap
(See 5.5 for details)
memory.limit_in_bytes # set/show limit of memory usage
memory.memsw.limit_in_bytes # set/show limit of memory+Swap usage
@@ -116,16 +121,16 @@ The memory controller is the first controller developed.
2.1. Design
-The core of the design is a counter called the res_counter. The res_counter
-tracks the current memory usage and limit of the group of processes associated
-with the controller. Each cgroup has a memory controller specific data
-structure (mem_cgroup) associated with it.
+The core of the design is a counter called the page_counter. The
+page_counter tracks the current memory usage and limit of the group of
+processes associated with the controller. Each cgroup has a memory controller
+specific data structure (mem_cgroup) associated with it.
2.2. Accounting
+--------------------+
- | mem_cgroup |
- | (res_counter) |
+ | mem_cgroup |
+ | (page_counter) |
+--------------------+
/ ^ \
/ | \
@@ -352,9 +357,8 @@ set:
0. Configuration
a. Enable CONFIG_CGROUPS
-b. Enable CONFIG_RESOURCE_COUNTERS
-c. Enable CONFIG_MEMCG
-d. Enable CONFIG_MEMCG_SWAP (to use swap extension)
+b. Enable CONFIG_MEMCG
+c. Enable CONFIG_MEMCG_SWAP (to use swap extension)
d. Enable CONFIG_MEMCG_KMEM (to use kmem extension)
1. Prepare the cgroups (see cgroups.txt, Why are cgroups needed?)