From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754261AbZCNINo (ORCPT ); Sat, 14 Mar 2009 04:13:44 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752557AbZCNINZ (ORCPT ); Sat, 14 Mar 2009 04:13:25 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:45503 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751624AbZCNINV (ORCPT ); Sat, 14 Mar 2009 04:13:21 -0400 Date: Sat, 14 Mar 2009 09:12:07 +0100 From: Ingo Molnar To: "Eric W. Biederman" Cc: Oren Laadan , Dave Hansen , linux-api@vger.kernel.org, containers@lists.linux-foundation.org, hpa@zytor.com, linux-kernel@vger.kernel.org, Alexey Dobriyan , linux-mm@kvack.org, viro@zeniv.linux.org.uk, mpm@selenic.com, Andrew Morton , Sukadev Bhattiprolu , Linus Torvalds , tglx@linutronix.de, xemul@openvz.org Subject: Re: How much of a mess does OpenVZ make? ;) Was: What can OpenVZ do? Message-ID: <20090314081207.GA16436@elte.hu> References: <1236891719.32630.14.camel@bahia> <20090312212124.GA25019@us.ibm.com> <604427e00903122129y37ad791aq5fe7ef2552415da9@mail.gmail.com> <20090313053458.GA28833@us.ibm.com> <20090313193500.GA2285@x200.localdomain> <1236981097.30142.251.camel@nimitz> <49BADAE5.8070900@cs.columbia.edu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Eric W. Biederman wrote: > >> In the OpenVZ case, they've at least demonstrated that the > >> filesystem can be moved largely with rsync. Unlinked files > >> need some in-kernel TLC (or /proc mangling) but it isn't > >> *that* bad. > > > > And in the Zap we have successfully used a log-based > > filesystem (specifically NILFS) to continuously snapshot the > > file-system atomically with taking a checkpoint, so it can > > easily branch off past checkpoints, including the file > > system. > > > > And unlinked files can be (inefficiently) handled by saving > > their full contents with the checkpoint image - it's not a > > big toll on many apps (if you exclude Wine and UML...). At > > least that's a start. > > Oren we might want to do a proof of concept implementation > like I did with network namespaces. That is done in the > community and goes far enough to show we don't have horribly > nasty code. The patches and individual changes don't need to > be quite perfect but close enough that they can be considered > for merging. > > For the network namespace that seems to have made a big > difference. > > I'm afraid in our clean start we may have focused a little too > much on merging something simple and not gone far enough on > showing that things will work. > > After I had that in the network namespace and we had a clear > vision of the direction. We started merging the individual > patches and things went well. I'm curious: what is the actual end result other than good looking code? In terms of tangible benefits to the everyday Linux distro user. [This is not meant to be sarcastic, i'm truly curious.] Ingo From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ingo Molnar Subject: Re: How much of a mess does OpenVZ make? ;) Was: What can OpenVZ do? Date: Sat, 14 Mar 2009 09:12:07 +0100 Message-ID: <20090314081207.GA16436@elte.hu> References: <1236891719.32630.14.camel@bahia> <20090312212124.GA25019@us.ibm.com> <604427e00903122129y37ad791aq5fe7ef2552415da9@mail.gmail.com> <20090313053458.GA28833@us.ibm.com> <20090313193500.GA2285@x200.localdomain> <1236981097.30142.251.camel@nimitz> <49BADAE5.8070900@cs.columbia.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Content-Disposition: inline In-Reply-To: Sender: owner-linux-mm@kvack.org To: "Eric W. Biederman" Cc: Oren Laadan , Dave Hansen , linux-api@vger.kernel.org, containers@lists.linux-foundation.org, hpa@zytor.com, linux-kernel@vger.kernel.org, Alexey Dobriyan , linux-mm@kvack.org, viro@zeniv.linux.org.uk, mpm@selenic.com, Andrew Morton , Sukadev Bhattiprolu , Linus Torvalds , tglx@linutronix.de, xemul@openvz.org List-Id: linux-api@vger.kernel.org * Eric W. Biederman wrote: > >> In the OpenVZ case, they've at least demonstrated that the > >> filesystem can be moved largely with rsync. Unlinked files > >> need some in-kernel TLC (or /proc mangling) but it isn't > >> *that* bad. > > > > And in the Zap we have successfully used a log-based > > filesystem (specifically NILFS) to continuously snapshot the > > file-system atomically with taking a checkpoint, so it can > > easily branch off past checkpoints, including the file > > system. > > > > And unlinked files can be (inefficiently) handled by saving > > their full contents with the checkpoint image - it's not a > > big toll on many apps (if you exclude Wine and UML...). At > > least that's a start. > > Oren we might want to do a proof of concept implementation > like I did with network namespaces. That is done in the > community and goes far enough to show we don't have horribly > nasty code. The patches and individual changes don't need to > be quite perfect but close enough that they can be considered > for merging. > > For the network namespace that seems to have made a big > difference. > > I'm afraid in our clean start we may have focused a little too > much on merging something simple and not gone far enough on > showing that things will work. > > After I had that in the network namespace and we had a clear > vision of the direction. We started merging the individual > patches and things went well. I'm curious: what is the actual end result other than good looking code? In terms of tangible benefits to the everyday Linux distro user. [This is not meant to be sarcastic, i'm truly curious.] Ingo -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org