From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Jacobowitz Subject: Re: [RFC v7][PATCH 2/9] General infrastructure for checkpoint restart Date: Wed, 22 Oct 2008 10:29:07 -0400 Message-ID: <20081022142907.GA13574@caradoc.them.org> 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 Return-path: Content-Disposition: inline In-Reply-To: <1224644563.1848.232.camel@nimitz> Sender: linux-api-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Dave Hansen Cc: Oren Laadan , linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org, mingo-X9Un+BFzKDI@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, viro-RmSDqhL/yNMiFSDQTTA3OLVCufUGDwFn@public.gmane.org, hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org, Andrew Morton , torvalds-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org List-Id: linux-api@vger.kernel.org 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-api" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html