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Date: Thu, 22 Jun 2006 11:35:08 -0700 (PDT)
From: Christoph Lameter <clameter@sgi.com>
To: Pavel Machek <pavel@suse.cz>
cc: "Randy.Dunlap" <rdunlap@xenotime.net>,
       KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>, ntl@pobox.com,
       akpm@osdl.org, linux-kernel@vger.kernel.org, ashok.raj@intel.com,
       ak@suse.de, nickpiggin@yahoo.com.au, mingo@elte.hu
Subject: Re: [PATCH] stop on cpu lost
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On Thu, 22 Jun 2006, Pavel Machek wrote:

> > > Hm..
> > > Then, there is several ways to manage this sitation.
> > > 
> > > 1. migrate all even if it's not allowed by users
> 
> That's what I'd prefer... as swsusp uses cpu hotplug. All the other
> options are bad... admin will probably not realize suspend involves
> cpu unplugs..

You probably first suspend a process? If a process was suspended by 
swsusp then we can just ignore the restriction because it will be 
returned later.

The admin wants the system to behave in a consistent way. If he suddenly 
finds a process running on a cpu that was forbidden then that is weird 
and surprising to say the least and may go undetected for a long time.
If the process gets killed when he disables the cpu then he will have to 
fix up his cpu restrictions.