Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030312AbWISACe (ORCPT ); Mon, 18 Sep 2006 20:02:34 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030316AbWISACd (ORCPT ); Mon, 18 Sep 2006 20:02:33 -0400 Received: from e31.co.us.ibm.com ([32.97.110.149]:20161 "EHLO e31.co.us.ibm.com") by vger.kernel.org with ESMTP id S1030312AbWISACc (ORCPT ); Mon, 18 Sep 2006 20:02:32 -0400 Subject: Re: [ckrm-tech] [Devel] Re: [PATCH] BC: resource beancounters (v4) (added user memory) From: Chandra Seetharaman Reply-To: sekharan@us.ibm.com To: Kir Kolyshkin Cc: rohitseth@google.com, devel@openvz.org, Rik van Riel , vatsa@in.ibm.com, CKRM-Tech , balbir@in.ibm.com, Linux Kernel Mailing List , Kirill Korotaev , Christoph Hellwig , Andrey Savochkin , Matt Helsley , Hugh Dickins , Alexey Dobriyan , Oleg Nesterov , Alan Cox , Andi Kleen In-Reply-To: <450B1958.3020309@openvz.org> 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> <1157743424.19884.65.camel@linuxchandra> <1157751834.1214.112.camel@galaxy.corp.google.com> <1157999107.6029.7.camel@linuxchandra> <1158001831.12947.16.camel@galaxy.corp.google.com> <20060912104410.GA28444@in.ibm.com> <1158081752.20211.12.camel@galaxy.corp.google.com> <1158105732.4800.26.camel@linuxchandra> <1158108203.20211.52.camel@galaxy.corp.google.com> <1158109991.4800.43.camel@linuxchandra> <1158111218.20211.69.camel@galaxy.corp.google.com> <1158186247.18927.11.camel@linuxchandra> <450A71B1.8020009@sw.ru> <1158339160.12311.35.camel@galaxy.corp.google.com> <450B1958.3020309@openvz.org> Content-Type: text/plain Organization: IBM Date: Mon, 18 Sep 2006 17:02:27 -0700 Message-Id: <1158624147.6536.13.camel@linuxchandra> Mime-Version: 1.0 X-Mailer: Evolution 2.0.4 (2.0.4-7) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3388 Lines: 71 On Sat, 2006-09-16 at 01:21 +0400, Kir Kolyshkin wrote: > Rohit Seth wrote: > > On Fri, 2006-09-15 at 13:26 +0400, Kirill Korotaev wrote: > > > > <...skipped...> > > > >> for VMware which can reserve required amount of RAM for VM. > >> > > > > It is much easier to provide guarantees in complete virtual > > environments. But then you pay the cost in terms of performance. > > > "Complete virtual environments" vs. "contaners" is not [only] about > performance! In the end, given a proper set of dirty and no-so-dirty > hacks in software and hardware, their performance will be close to native. > > Containers vs. other virtualization types is more about utilization, > density, scalability, portability. > > Speaking of guarantees, yes, guarantees is easy, you just reserve such > amount of RAM for your VM and that is all. But the fact is usually some > part of that RAM will not be utilized by this particular VM. But since > it is reserved, it can not be utilized by other VMs -- and we end up > just wasting some resources. Containers, given a proper resource > management and configuration, can have some guarantees and still be able > to utilize all the RAM available in the system. This difference can be > metaphorically expressed as a house divided into rooms. Dividing walls > can either be hard or flexible. With flexible walls, room (container) > owner have a guarantee of minimal space in your room, but if a few > guests come for a moment, the walls can move to make more space (up to > the limit). So the flexibility is measured as the delta between a > guarantee and a limit. > > This flexibility leads to higher utilization, and this flexibility is > one of the reasons for better density (a few times higher than that of a > paravirtualization solution). > > I will not touch scalability and portability topics here to make things > simpler. > > I think we should punt on hard guarantees and fractions for the first > > draft. Keep the implementation simple. > > > Do I understand it right that with hard guarantees we loose the > flexibility I have just described? If this is the case, I do not like it. > If I understand your description correctly (describing flexibility to be the ability to move the resource usage between guarantee and limit), then NO, you will not loose that flexibility. > ------------------------------------------------------------------------- > Using Tomcat but need to do more? Need to support web services, security? > Get stuff done quickly with pre-integrated technology to make your job easier > Download IBM WebSphere Application Server v.1.0.1 based on Apache Geronimo > http://sel.as-us.falkag.net/sel?cmd=lnk&kid=120709&bid=263057&dat=121642 > _______________________________________________ > ckrm-tech mailing list > https://lists.sourceforge.net/lists/listinfo/ckrm-tech -- ---------------------------------------------------------------------- Chandra Seetharaman | Be careful what you choose.... - sekharan@us.ibm.com | .......you may get it. ---------------------------------------------------------------------- - 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/