Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755885AbYJVO3V (ORCPT ); Wed, 22 Oct 2008 10:29:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752588AbYJVO3M (ORCPT ); Wed, 22 Oct 2008 10:29:12 -0400 Received: from NaN.false.org ([208.75.86.248]:33843 "EHLO nan.false.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752553AbYJVO3K (ORCPT ); Wed, 22 Oct 2008 10:29:10 -0400 Date: Wed, 22 Oct 2008 10:29:07 -0400 From: Daniel Jacobowitz To: Dave Hansen Cc: Oren Laadan , linux-api@vger.kernel.org, containers@lists.linux-foundation.org, mingo@elte.hu, linux-kernel@vger.kernel.org, linux-mm@kvack.org, viro@zeniv.linux.org.uk, hpa@zytor.com, Andrew Morton , torvalds@linux-foundation.org, tglx@linutronix.de Subject: Re: [RFC v7][PATCH 2/9] General infrastructure for checkpoint restart Message-ID: <20081022142907.GA13574@caradoc.them.org> Mail-Followup-To: Dave Hansen , Oren Laadan , linux-api@vger.kernel.org, containers@lists.linux-foundation.org, mingo@elte.hu, linux-kernel@vger.kernel.org, linux-mm@kvack.org, viro@zeniv.linux.org.uk, hpa@zytor.com, Andrew Morton , torvalds@linux-foundation.org, tglx@linutronix.de References: <1224481237-4892-1-git-send-email-orenl@cs.columbia.edu> <1224481237-4892-3-git-send-email-orenl@cs.columbia.edu> <20081021124130.a002e838.akpm@linux-foundation.org> <20081021202410.GA10423@us.ibm.com> <48FE82DF.6030005@cs.columbia.edu> <20081022025513.GA7504@caradoc.them.org> <1224644563.1848.232.camel@nimitz> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1224644563.1848.232.camel@nimitz> User-Agent: Mutt/1.5.17 (2008-05-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 979 Lines: 22 On Tue, Oct 21, 2008 at 08:02:43PM -0700, Dave Hansen wrote: > Let's say you have a process you want to checkpoint. If it uses a > completely discrete IPC namespace, you *know* that nothing else depends > on those IPC ids. We don't even have to worry about who might have been > using them and when. > > Also think about pids. Without containers, how can you guarantee a > restarted process that it can regain the same pid? OK, that makes sense. In a lot of simple cases you can get by without regaining the same pid; there's an implementation of checkpointing in GDB that works by injecting fork calls into the child, and it is useful for a reasonable selection of single-threaded programs. -- Daniel Jacobowitz CodeSourcery -- 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/