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Date: Thu, 12 Feb 2009 11:42:07 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Matt Mackall <mpm@selenic.com>
Cc: dave@linux.vnet.ibm.com, mingo@elte.hu, orenl@cs.columbia.edu,
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Subject: Re: [RFC v13][PATCH 00/14] Kernel based checkpoint/restart
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On Thu, 12 Feb 2009 13:30:35 -0600
Matt Mackall <mpm@selenic.com> wrote:

> On Thu, 2009-02-12 at 10:11 -0800, Dave Hansen wrote:
> 
> > > - In bullet-point form, what features are missing, and should be added?
> > 
> >  * support for more architectures than i386
> >  * file descriptors:
> >   * sockets (network, AF_UNIX, etc...)
> >   * devices files
> >   * shmfs, hugetlbfs
> >   * epoll
> >   * unlinked files
> 
> >  * Filesystem state
> >   * contents of files
> >   * mount tree for individual processes
> >  * flock
> >  * threads and sessions
> >  * CPU and NUMA affinity
> >  * sys_remap_file_pages()
> 
> I think the real questions is: where are the dragons hiding? Some of
> these are known to be hard. And some of them are critical checkpointing
> typical applications. If you have plans or theories for implementing all
> of the above, then great. But this list doesn't really give any sense of
> whether we should be scared of what lurks behind those doors.

How close has OpenVZ come to implementing all of this?  I think the
implementatation is fairly complete?

If so, perhaps that can be used as a guide.  Will the planned feature
have a similar design?  If not, how will it differ?  To what extent can
we use that implementation as a tool for understanding what this new
implementation will look like?