On Sun, 3 Oct 2010 23:57:57 -0700 Greg Thelen <gthelen@xxxxxxxxxx> wrote: > Document cgroup dirty memory interfaces and statistics. > > Signed-off-by: Andrea Righi <arighi@xxxxxxxxxxx> > Signed-off-by: Greg Thelen <gthelen@xxxxxxxxxx> Nice. Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@xxxxxxxxxxxxxx> > --- > Documentation/cgroups/memory.txt | 37 +++++++++++++++++++++++++++++++++++++ > 1 files changed, 37 insertions(+), 0 deletions(-) > > diff --git a/Documentation/cgroups/memory.txt b/Documentation/cgroups/memory.txt > index 7781857..eab65e2 100644 > --- a/Documentation/cgroups/memory.txt > +++ b/Documentation/cgroups/memory.txt > @@ -385,6 +385,10 @@ mapped_file - # of bytes of mapped file (includes tmpfs/shmem) > pgpgin - # of pages paged in (equivalent to # of charging events). > pgpgout - # of pages paged out (equivalent to # of uncharging events). > swap - # of bytes of swap usage > +dirty - # of bytes that are waiting to get written back to the disk. > +writeback - # of bytes that are actively being written back to the disk. > +nfs - # of bytes sent to the NFS server, but not yet committed to > + the actual storage. > inactive_anon - # of bytes of anonymous memory and swap cache memory on > LRU list. > active_anon - # of bytes of anonymous and swap cache memory on active > @@ -453,6 +457,39 @@ memory under it will be reclaimed. > You can reset failcnt by writing 0 to failcnt file. > # echo 0 > .../memory.failcnt > > +5.5 dirty memory > + > +Control the maximum amount of dirty pages a cgroup can have at any given time. > + > +Limiting dirty memory is like fixing the max amount of dirty (hard to reclaim) > +page cache used by a cgroup. So, in case of multiple cgroup writers, they will > +not be able to consume more than their designated share of dirty pages and will > +be forced to perform write-out if they cross that limit. > + > +The interface is equivalent to the procfs interface: /proc/sys/vm/dirty_*. It > +is possible to configure a limit to trigger both a direct writeback or a > +background writeback performed by per-bdi flusher threads. The root cgroup > +memory.dirty_* control files are read-only and match the contents of > +the /proc/sys/vm/dirty_* files. > + > +Per-cgroup dirty limits can be set using the following files in the cgroupfs: > + > +- memory.dirty_ratio: the amount of dirty memory (expressed as a percentage of > + cgroup memory) at which a process generating dirty pages will itself start > + writing out dirty data. > + > +- memory.dirty_bytes: the amount of dirty memory (expressed in bytes) in the > + cgroup at which a process generating dirty pages will start itself writing out > + dirty data. > + > +- memory.dirty_background_ratio: the amount of dirty memory of the cgroup > + (expressed as a percentage of cgroup memory) at which background writeback > + kernel threads will start writing out dirty data. > + > +- memory.dirty_background_bytes: the amount of dirty memory (expressed in bytes) > + in the cgroup at which background writeback kernel threads will start writing > + out dirty data. > + > 6. Hierarchy support > > The memory controller supports a deep hierarchy and hierarchical accounting. > -- > 1.7.1 > > -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxxx For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>