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Date: Wed, 31 Aug 2011 08:45:33 +0200
From: Jiri Slaby <jslaby@suse.cz>
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To: Andrew Morton <akpm@linux-foundation.org>
CC: Andi Kleen <ak@linux.intel.com>, Andi Kleen <andi@firstfloor.org>,
        linux-kernel@vger.kernel.org, eric.dumazet@gmail.com
Subject: Re: [PATCH 2/4] posix-timers: limit the number of posix timers per
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On 08/31/2011 01:02 AM, Andrew Morton wrote:
> On Tue, 30 Aug 2011 15:47:47 -0700
> Andi Kleen<ak@linux.intel.com>  wrote:
>
>>
>>> Yes, deployment for new rlimits is a big PITA.  It would be sensible to
>>> modify the shells to take some anonymous numeric argument, so you could
>>> do
>>>
>>> 	ulimit 42 1000
>>>
>>> to set rlimit number 42 if your shell version doesn't understand the
>>> symbolic representation of more recent additions.  Who do I call?
>>
>> I guess sending a patch to the bash maintainers?
>>
>
> That would help ;)  And all the other shells :(
>
> It would be worth going back and taking another look at the writable
> /proc/<pid>/limits patches (http://lwn.net/Articles/365732/).  Why
> didn't that work get merged?

This turned out to be too heavy-weight. We ended up having prlimit64 
syscall. I.e. most of the pull request was merged. But not the 2 patches 
for writable /proc/.../limits.

With that syscall we might augment coreutils (or better kernel/tools to 
be updated properly) by a tool such as `prlimit', I think. Actually 
something I had when I was testing the syscall:
https://github.com/jirislaby/collected_sources/blob/master/lim/lim.c#L1

regards,
-- 
js
suse labs