Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751244AbWIKIN6 (ORCPT ); Mon, 11 Sep 2006 04:13:58 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751247AbWIKIN6 (ORCPT ); Mon, 11 Sep 2006 04:13:58 -0400 Received: from mailhub.sw.ru ([195.214.233.200]:25198 "EHLO relay.sw.ru") by vger.kernel.org with ESMTP id S1751244AbWIKIN5 (ORCPT ); Mon, 11 Sep 2006 04:13:57 -0400 Message-ID: <45051AC7.2000607@openvz.org> Date: Mon, 11 Sep 2006 12:13:59 +0400 From: Pavel Emelianov User-Agent: Thunderbird 1.5 (X11/20060317) MIME-Version: 1.0 To: balbir@in.ibm.com CC: Dave Hansen , Rik van Riel , Srivatsa , sekharan@us.ibm.com, Alan Cox , CKRM-Tech , Andi Kleen , Linux Kernel Mailing List , Christoph Hellwig , Andrey Savochkin , Matt Helsley , Hugh Dickins , Alexey Dobriyan , Kirill Korotaev , Oleg Nesterov , devel@openvz.org Subject: Re: [ckrm-tech] [PATCH] BC: resource beancounters (v4) (added user memory) References: <44FD918A.7050501@sw.ru> <44FDAB81.5050608@in.ibm.com> <44FEC7E4.7030708@sw.ru> <44FF1EE4.3060005@in.ibm.com> <1157580371.31893.36.camel@linuxchandra> <45011CAC.2040502@openvz.org> <1157730221.26324.52.camel@localhost.localdomain> <4501B5F0.9050802@in.ibm.com> <450508BB.7020609@openvz.org> <4505161E.1040401@in.ibm.com> In-Reply-To: <4505161E.1040401@in.ibm.com> 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: 2323 Lines: 57 Balbir Singh wrote: > Pavel Emelianov wrote: >> Balbir Singh wrote: >>> Dave Hansen wrote: >>>> On Fri, 2006-09-08 at 11:33 +0400, Pavel Emelianov wrote: >>>>> I'm afraid we have different understandings of what a "guarantee" is. >>>> It appears so. >>>> >>>>> Don't we? >>>>> Guarantee may be one of >>>>> >>>>> 1. container will be able to touch that number of pages >>>>> 2. container will be able to sys_mmap() that number of pages >>>>> 3. container will not be killed unless it touches that number of >>>>> pages >>>> A "death sentence" guarantee? I like it. :) >>>> >>>>> 4. anything else >>>>> >>>>> Let's decide what kind of a guarantee we want. >>> I think of guarantees w.r.t resources as the lower limit on the >>> resource. >>> Guarantees and limits can be thought of as the range (guarantee, limit] >>> for the usage of the resource. >>> >>>> I think of it as: "I will be allowed to use this many total pages, and >>>> they are guaranteed not to fail." (1), I think. The sum of all of >>>> the >>>> system's guarantees must be less than or equal to the amount of free >>>> memory on the machine. >>> Yes, totally agree. >> >> Such a guarantee is really a limit and this limit is even harder than >> BC's one :) >> >> E.g. I have a node with 1Gb of ram and 10 containers with 100Mb >> guarantee each. >> I want to start one more. What shall I do not to break guarantees? > > Don't start the new container or change the guarantees of the existing > ones > to accommodate this one :) The QoS design (done by the administrator) > should > take care of such use-cases. It would be perfectly ok to have a container > that does not care about guarantees to set their guarantee to 0 and set > their limit to the desired value. As Chandra has been stating we need two > parameters (guarantee, limit), either can be optional, but not both. If I set up 9 groups to have 100Mb limit then I have 100Mb assured (on 1Gb node) for the 10th one exactly. And I do not have to set up any guarantee as it won't affect anything. So what a guarantee parameter is needed for? - 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/