From mboxrd@z Thu Jan 1 00:00:00 1970 From: KAMEZAWA Hiroyuki Subject: Re: [PATCH 09/23] kmem slab accounting basic infrastructure Date: Wed, 25 Apr 2012 10:32:32 +0900 Message-ID: <4F975430.4090107@jp.fujitsu.com> References: <1334959051-18203-1-git-send-email-glommer@parallels.com> <1334959051-18203-10-git-send-email-glommer@parallels.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1334959051-18203-10-git-send-email-glommer-bzQdu9zFT3WakBO8gow8eQ@public.gmane.org> Sender: cgroups-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-ID: Content-Type: text/plain; charset="us-ascii" To: Glauber Costa Cc: cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devel-GEFAQzZX7r8dnm+yROfE0A@public.gmane.org, Michal Hocko , Johannes Weiner , Frederic Weisbecker , Greg Thelen , Suleiman Souhlal (2012/04/21 6:57), Glauber Costa wrote: > This patch adds the basic infrastructure for the accounting of the slab > caches. To control that, the following files are created: > > * memory.kmem.usage_in_bytes > * memory.kmem.limit_in_bytes > * memory.kmem.failcnt > * memory.kmem.max_usage_in_bytes > > They have the same meaning of their user memory counterparts. They reflect > the state of the "kmem" res_counter. > > The code is not enabled until a limit is set. This can be tested by the flag > "kmem_accounted". This means that after the patch is applied, no behavioral > changes exists for whoever is still using memcg to control their memory usage. > Hmm, res_counter never goes naeative ? > We always account to both user and kernel resource_counters. This effectively > means that an independent kernel limit is in place when the limit is set > to a lower value than the user memory. A equal or higher value means that the > user limit will always hit first, meaning that kmem is effectively unlimited. > > People who want to track kernel memory but not limit it, can set this limit > to a very high number (like RESOURCE_MAX - 1page - that no one will ever hit, > or equal to the user memory) > > Signed-off-by: Glauber Costa > CC: Michal Hocko > CC: Kamezawa Hiroyuki > CC: Johannes Weiner The code itself seems fine. Reviewed-by: KAMEZAWA Hiroyuki