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Subject: Re: +
 prctl-add-pr_setget_child_reaper-to-allow-simple-process-supervision .patch
 added to -mm tree
From: Kay Sievers <kay.sievers@vrfy.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>, Lennart Poettering <mzxreary@0pointer.de>,
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Date: Fri, 19 Aug 2011 02:48:31 +0200
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On Thu, 2011-08-18 at 15:22 -0700, Linus Torvalds wrote:
> On Thu, Aug 18, 2011 at 2:55 PM, Kay Sievers <kay.sievers@vrfy.org> wrote:
> >
> > It will be used for all new service managers. UNIX is a pain if you want
> > to watch your children regarding double-forking, if you are not init.
> 
> I'll believe that "all new service managers" when I see it. Until
> then, a new feature is just that - a new feature. Which nobody uses.

That feature will be used in Fedora 17 if we get that properly working.
Promised!

So far we have a pretty good track record in immediately using the stuff
we add to the kernel. People working on the other side usually complain
that we always require such new kernels. :)

> > If you want, we can make the forked processes inherit a flag if the
> > 'subreaper' should be looked up at all. Then we have almost zero
> > overhead if the feature isn't used. You think that's needed?
> 
> Yes, I do. Because with any current system, that "almost zero
> overhead" is just totally wasted effort entirely for zero gain. Which
> just makes me go "Eww".

Yeah, understood. I'll change it with the next round, and we can see how
to go from there.

Thanks,
Kay