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Date: Sat, 14 Mar 2009 03:20:59 +0300
From: Alexey Dobriyan <adobriyan@gmail.com>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>,
       Ying Han <yinghan@google.com>, "Serge E. Hallyn" <serue@us.ibm.com>,
       linux-api@vger.kernel.org, containers@lists.linux-foundation.org,
       hpa@zytor.com, linux-kernel@vger.kernel.org,
       Dave Hansen <dave@linux.vnet.ibm.com>, linux-mm@kvack.org,
       viro@zeniv.linux.org.uk, mingo@elte.hu, mpm@selenic.com,
       Andrew Morton <akpm@linux-foundation.org>, xemul@openvz.org,
       tglx@linutronix.de
Subject: Re: How much of a mess does OpenVZ make? ;) Was: What can OpenVZ
	do?
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On Fri, Mar 13, 2009 at 02:01:50PM -0700, Linus Torvalds wrote:
> 
> 
> On Fri, 13 Mar 2009, Alexey Dobriyan wrote:
> > > 
> > > Let's face it, we're not going to _ever_ checkpoint any kind of general 
> > > case process. Just TCP makes that fundamentally impossible in the general 
> > > case, and there are lots and lots of other cases too (just something as 
> > > totally _trivial_ as all the files in the filesystem that don't get rolled 
> > > back).
> > 
> > What do you mean here? Unlinked files?
> 
> Or modified files, or anything else. "External state" is a pretty damn 
> wide net. It's not just TCP sequence numbers and another machine.

I think (I think) you're seriously underestimating what's doable with
kernel C/R and what's already done.

I was told (haven't seen it myself) that Oracle installations and
Counter Strike servers were moved between boxes just fine.

They were run in specially prepared environment of course, but still.