From mboxrd@z Thu Jan 1 00:00:00 1970 From: Greg Thelen Subject: [PATCH 02/10] memcg: document cgroup dirty memory interfaces Date: Sun, 3 Oct 2010 23:57:57 -0700 Message-ID: <1286175485-30643-3-git-send-email-gthelen@google.com> References: <1286175485-30643-1-git-send-email-gthelen@google.com> Return-path: In-Reply-To: <1286175485-30643-1-git-send-email-gthelen@google.com> Sender: owner-linux-mm@kvack.org To: Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, containers@lists.osdl.org, Andrea Righi , Balbir Singh , KAMEZAWA Hiroyuki , Daisuke Nishimura , Greg Thelen List-Id: containers.vger.kernel.org Document cgroup dirty memory interfaces and statistics. Signed-off-by: Andrea Righi Signed-off-by: Greg Thelen --- 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@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752826Ab0JDHCD (ORCPT ); Mon, 4 Oct 2010 03:02:03 -0400 Received: from smtp-out.google.com ([74.125.121.35]:32459 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752185Ab0JDHCB (ORCPT ); Mon, 4 Oct 2010 03:02:01 -0400 DomainKey-Signature: a=rsa-sha1; s=beta; d=google.com; c=nofws; q=dns; h=from:to:cc:subject:date:message-id:x-mailer:in-reply-to:references; b=u+lysIq+PZtAUsixPx5AyovMtHrKbTwh9aD/vxumnTvXBw+aWC57aQqsy0DaA+lyv xqRRYTAoWtQGACKENB7FA== From: Greg Thelen To: Andrew Morton Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, containers@lists.osdl.org, Andrea Righi , Balbir Singh , KAMEZAWA Hiroyuki , Daisuke Nishimura , Greg Thelen Subject: [PATCH 02/10] memcg: document cgroup dirty memory interfaces Date: Sun, 3 Oct 2010 23:57:57 -0700 Message-Id: <1286175485-30643-3-git-send-email-gthelen@google.com> X-Mailer: git-send-email 1.7.1 In-Reply-To: <1286175485-30643-1-git-send-email-gthelen@google.com> References: <1286175485-30643-1-git-send-email-gthelen@google.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Document cgroup dirty memory interfaces and statistics. Signed-off-by: Andrea Righi Signed-off-by: Greg Thelen --- 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