lkml.org 
[lkml]   [2008]   [Nov]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Date
    Subject[mm] [PATCH 1/4] Memory cgroup hierarchy documentation


    Documentation updates for hierarchy support

    Signed-off-by: Balbir Singh <balbir@linux.vnet.ibm.com>
    ---

    Documentation/controllers/memory.txt | 34 ++++++++++++++++++++++++++++++++++
    1 file changed, 34 insertions(+)

    diff -puN Documentation/controllers/memory.txt~memcg-hierarchy-documentation Documentation/controllers/memory.txt
    --- linux-2.6.28-rc2/Documentation/controllers/memory.txt~memcg-hierarchy-documentation 2008-11-02 00:14:54.000000000 +0530
    +++ linux-2.6.28-rc2-balbir/Documentation/controllers/memory.txt 2008-11-02 00:14:54.000000000 +0530
    @@ -245,6 +245,40 @@ cgroup might have some charge associated
    tasks have migrated away from it. Such charges are automatically dropped at
    rmdir() if there are no tasks.

    +5. Hierarchy support
    +
    +The memory controller supports a deep hierarchy and hierarchical accounting.
    +The hierarchy is created by creating the appropriate cgroups in the
    +cgroup filesystem. Consider for example, the following cgroup filesystem
    +hierarchy
    +
    + root
    + / | \
    + / | \
    + a b c
    + | \
    + | \
    + 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).
    +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.
    +
    +5.1 Enabling hierarchical accounting and reclaim
    +
    +The memory controller by default disables the hierarchy feature. Support
    +can be enabled by writing 1 to memory.features file of the root cgroup
    +
    +# echo 1 > memory.features
    +
    +The feature can be disabled by
    +
    +# echo 0 > memory.features
    +
    +NOTE: Enabling/disabling will fail if the root cgroup already has other
    +cgroups created below it.
    +
    5. TODO

    1. Add support for accounting huge pages (as a separate controller)
    _
    --
    Balbir


    \
     
     \ /
      Last update: 2008-11-01 19:51    [W:0.030 / U:91.912 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site