Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751681AbWIHHWs (ORCPT ); Fri, 8 Sep 2006 03:22:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751910AbWIHHWs (ORCPT ); Fri, 8 Sep 2006 03:22:48 -0400 Received: from mailhub.sw.ru ([195.214.233.200]:30884 "EHLO relay.sw.ru") by vger.kernel.org with ESMTP id S1751681AbWIHHWq (ORCPT ); Fri, 8 Sep 2006 03:22:46 -0400 Message-ID: <45011A47.1020407@openvz.org> Date: Fri, 08 Sep 2006 11:22:47 +0400 From: Pavel Emelianov User-Agent: Thunderbird 1.5 (X11/20060317) MIME-Version: 1.0 To: sekharan@us.ibm.com CC: Kirill Korotaev , Dave Hansen , Rik van Riel , CKRM-Tech , Linux Kernel Mailing List , Andi Kleen , Christoph Hellwig , Andrey Savochkin , devel@openvz.org, Hugh Dickins , Matt Helsley , Alexey Dobriyan , Oleg Nesterov , Alan Cox Subject: Re: [ckrm-tech] [PATCH] BC: resource beancounters (v4) (added user memory) References: <44FD918A.7050501@sw.ru> <1157478392.3186.26.camel@localhost.localdomain> <44FED3CA.7000005@sw.ru> <1157579641.31893.26.camel@linuxchandra> <44FFCA4D.9090202@openvz.org> <1157656616.19884.34.camel@linuxchandra> In-Reply-To: <1157656616.19884.34.camel@linuxchandra> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1754 Lines: 43 Chandra Seetharaman wrote: [snip] >>>> The question is - whether web server is multithreaded or not... >>>> If it is not - then no problem here, you can change current >>>> context and new resources will be charged accordingly. >>>> >>>> And current BC code is _able_ to handle it with _minor_ changes. >>>> (One just need to save bc not on mm struct, but rather on vma struct >>>> and change mm->bc on set_bc_id()). >>>> >>>> However, no one (can some one from CKRM team please?) explained so far >>>> what to do with threads. Consider the following example. >>>> >>>> 1. Threaded web server spawns a child to serve a client. >>>> 2. child thread touches some pages and they are charged to child BC >>>> (which differs from parent's one) >>>> 3. child exits, but since its mm is shared with parent, these pages >>>> stay mapped and charged to child BC. >>>> >>>> So the question is: what to do with these pages? >>>> - should we recharge them to another BC? >>>> - leave them charged? >>>> >>>> >>> Leave them charged. It will be charged to the appropriate UBC when they >>> touch it again. >>> >>> >> Do you mean that page must be re-charged each time someone touches it? >> > > What I meant is that to leave them charged, and if when they are > ummapped and mapped later, charge it to the appropriate BC. > In this case multithreaded apache that tries to serve each domain in separate BC will fill the memory with BC-s, held by pages allocated and mapped in threads. - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/