From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with ESMTP id C94326B0044 for ; Wed, 7 Jan 2009 13:41:15 -0500 (EST) Received: from d28relay04.in.ibm.com (d28relay04.in.ibm.com [9.184.220.61]) by e28smtp06.in.ibm.com (8.13.1/8.13.1) with ESMTP id n07If9Tp029398 for ; Thu, 8 Jan 2009 00:11:09 +0530 Received: from d28av04.in.ibm.com (d28av04.in.ibm.com [9.184.220.66]) by d28relay04.in.ibm.com (8.13.8/8.13.8/NCO v9.1) with ESMTP id n07IfD7v4362360 for ; Thu, 8 Jan 2009 00:11:13 +0530 Received: from d28av04.in.ibm.com (loopback [127.0.0.1]) by d28av04.in.ibm.com (8.13.1/8.13.3) with ESMTP id n07If8bl023185 for ; Thu, 8 Jan 2009 05:41:08 +1100 From: Balbir Singh Date: Thu, 08 Jan 2009 00:11:10 +0530 Message-Id: <20090107184110.18062.41459.sendpatchset@localhost.localdomain> Subject: [RFC][PATCH 0/4] Memory controller soft limit patches Sender: owner-linux-mm@kvack.org To: Andrew Morton Cc: Sudhir Kumar , YAMAMOTO Takashi , Paul Menage , lizf@cn.fujitsu.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, David Rientjes , Pavel Emelianov , Balbir Singh , KAMEZAWA Hiroyuki List-ID: Here is v1 of the new soft limit implementation. Soft limits is a new feature for the memory resource controller, something similar has existed in the group scheduler in the form of shares. We'll compare shares and soft limits below. I've had soft limit implementations earlier, but I've discarded those approaches in favour of this one. Soft limits are the most useful feature to have for environments where the administrator wants to overcommit the system, such that only on memory contention do the limits become active. The current soft limits implementation provides a soft_limit_in_bytes interface for the memory controller and not for memory+swap controller. The implementation maintains an RB-Tree of groups that exceed their soft limit and starts reclaiming from the group that exceeds this limit by the maximum amount. This is an RFC implementation and is not meant for inclusion TODOs 1. The shares interface is not yet implemented, the current soft limit implementation is not yet hierarchy aware. The end goal is to add a shares interface on top of soft limits and to maintain shares in a manner similar to the group scheduler 2. The current implementation maintains the delta from the soft limit and pushes back groups to their soft limits, a ratio of delta/soft_limit is more useful 3. It would be nice to have more targetted reclaim (in terms of pages to recalim) interface. So that groups are pushed back, close to their soft limits. Tests ----- I've run two memory intensive workloads with differing soft limits and seen that they are pushed back to their soft limit on contention. Their usage was their soft limit plus additional memory that they were able to grab on the system. Please review, comment. Series ------ memcg-soft-limit-documentation.patch memcg-add-soft-limit-interface.patch memcg-organize-over-soft-limit-groups.patch memcg-soft-limit-reclaim-on-contention.patch -- Balbir -- 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