From mboxrd@z Thu Jan 1 00:00:00 1970 From: KAMEZAWA Hiroyuki Subject: Re: [PATCH 3/9] bio-cgroup controller Date: Fri, 17 Apr 2009 17:00:16 +0900 Message-ID: <20090417170016.5c7268f1.kamezawa.hiroyu__22560.9269728468$1239955635$gmane$org@jp.fujitsu.com> References: <1239740480-28125-4-git-send-email-righi.andrea@gmail.com> <49E7E037.9080004@oss.ntt.co.jp> <20090417112433.085ed604.kamezawa.hiroyu@jp.fujitsu.com> <20090417.162201.183038478.ryov@valinux.co.jp> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20090417.162201.183038478.ryov-jCdQPDEk3idL9jVzuh4AOg@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org Errors-To: containers-bounces-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org To: Ryo Tsuruta Cc: randy.dunlap-QHcLZuEGTsvQT0dZR+AlfA@public.gmane.org, menage-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, chlunde-om2ZC0WAoZIXWF+eFR7m5Q@public.gmane.org, eric.rannaud-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, balbir-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org, fernando-gVGce1chcLdL9jVzuh4AOg@public.gmane.org, righi.andrea-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org, dradford-cT2on/YLNlBWk0Htik3J/w@public.gmane.org, agk-9JcytcrH/bA+uJoB2kUjGw@public.gmane.org, subrata-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org, axboe-tSWWG44O7X1aa/9Udqfwiw@public.gmane.org, akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, dave-23VcF4HTsmIX0ybBhKVfKdBPR1lH4CV8@public.gmane.org, matt-cT2on/YLNlBWk0Htik3J/w@public.gmane.org, roberto-5KDOxZqKugI@public.gmane.org, ngupta-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org List-Id: containers.vger.kernel.org On Fri, 17 Apr 2009 16:22:01 +0900 (JST) Ryo Tsuruta wrote: > In the case where the bio-cgroup data is allocated dynamically, > - Sometimes quite a large amount of memory get marked dirty. > In this case it requires more kernel memory than that of the > current implementation. > - The operation is expansive due to memory allocations and exclusive > controls by such as spinlocks. > > In the case where the bio-cgroup data is allocated by delayed allocation, > - It makes the operation complicated and expensive, because > sometimes a bio has to be created in the context of other > processes, such as aio and swap-out operation. > > I'd prefer a simple and lightweight implementation. bio-cgroup only > needs 4bytes unlike memory controller. The reason why bio-cgroup chose > this approach is to minimize the overhead. > My point is, plz do your best to reduce memory usage here. You increase size of page_cgroup just because you cannot increase size of struct page. It's not be sane reason to increase size of this object. It's a cheat in my point of view. Thanks, -Kame