Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030286AbWBTP1f (ORCPT ); Mon, 20 Feb 2006 10:27:35 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1030291AbWBTP1f (ORCPT ); Mon, 20 Feb 2006 10:27:35 -0500 Received: from MAIL.13thfloor.at ([212.16.62.50]:3812 "EHLO mail.13thfloor.at") by vger.kernel.org with ESMTP id S1030286AbWBTP1e (ORCPT ); Mon, 20 Feb 2006 10:27:34 -0500 Date: Mon, 20 Feb 2006 16:27:33 +0100 From: Herbert Poetzl To: Kirill Korotaev Cc: "Serge E. Hallyn" , "Eric W. Biederman" , linux-kernel@vger.kernel.org, vserver@list.linux-vserver.org, Alan Cox , Dave Hansen , Arjan van de Ven , Suleiman Souhlal , Hubertus Franke , Cedric Le Goater , Kyle Moffett , Greg , Linus Torvalds , Andrew Morton , Greg KH , Rik van Riel , Alexey Kuznetsov , Andrey Savochkin , Kirill Korotaev , Andi Kleen , Benjamin Herrenschmidt , Jeff Garzik , Trond Myklebust , Jes Sorensen Subject: Re: (pspace,pid) vs true pid virtualization Message-ID: <20060220152732.GC18841@MAIL.13thfloor.at> Mail-Followup-To: Kirill Korotaev , "Serge E. Hallyn" , "Eric W. Biederman" , linux-kernel@vger.kernel.org, vserver@list.linux-vserver.org, Alan Cox , Dave Hansen , Arjan van de Ven , Suleiman Souhlal , Hubertus Franke , Cedric Le Goater , Kyle Moffett , Greg , Linus Torvalds , Andrew Morton , Greg KH , Rik van Riel , Alexey Kuznetsov , Andrey Savochkin , Kirill Korotaev , Andi Kleen , Benjamin Herrenschmidt , Jeff Garzik , Trond Myklebust , Jes Sorensen References: <20060215145942.GA9274@sergelap.austin.ibm.com> <20060216142928.GA22358@sergelap.austin.ibm.com> <43F98DD5.40107@sw.ru> <20060220124745.GC17478@MAIL.13thfloor.at> <43F9D379.5000803@sw.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <43F9D379.5000803@sw.ru> User-Agent: Mutt/1.5.6i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2468 Lines: 70 On Mon, Feb 20, 2006 at 05:34:33PM +0300, Kirill Korotaev wrote: >>> yes, acceptable. >>> once, again, believe me, this is very required feature for >>> troubleshouting and management (as Eric likes to take about >>> maintanance :) ) > >> IMHO there are certain things which _are_ required >> and others which are nice to have but not strictly >> required, just think "ptrace across pid spaces" > these "nice to have" features often make one solution more usable than > another. agreed, but do you really have to strace the OpenVZ tools so often, as I don't see any other purpose for cross space strace. usually you strace either inside or outside the space, as the transition is not that well defined anyway ... >>>> This is to support using pidspaces for vservers, and creating >>>> migrateable sub-pidspaces in each vserver. >>> this doesn't help to create migratable sub-pidspaces. >>> for example, will you share IPCs in your pid parent and child pspaces? >>> if yes, then it won't be migratable; >> well, not the child pspace, but the parent, no? > if IPC objects are shared between them, then they can only be migrated > together. not all spaces will be done fur the purpose of migration, some of them might have other purposes >>> if no, then you need to create fully isolated spaces to the end and >>> again you end up with a question, why nested pspaces are required at >>> all? >> because we are not trying to implement a VPS only >> solution for mainline, we are trying to provide >> building blocks for many different uses, including >> the VPS approach ... > nice! do you think I'm against building blocks? no :) > I'm just trying to get out from you how this can be used in real > life and how will it work. ah, I'm glad to share my experience here ... the linux-vserver.org wiki shows some of those real world usage scenarios, which include, but are not limited to: - Administrative Separation - Service Separation - Enhancing Security (better chroot) - Easy Maintenance (hardware independance) - Testing most application scenarios do not require a complete VPS or Guest to make them usable, often only a single * space would suffice to accomplish the goal ... best, Herbert > Kirill - 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/