Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752669Ab1CJJqS (ORCPT ); Thu, 10 Mar 2011 04:46:18 -0500 Received: from mailhub.sw.ru ([195.214.232.25]:25616 "EHLO relay.sw.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752049Ab1CJJqQ (ORCPT ); Thu, 10 Mar 2011 04:46:16 -0500 Message-ID: <4D789B64.9000603@parallels.com> Date: Thu, 10 Mar 2011 12:35:32 +0300 From: Pavel Emelyanov User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.11) Gecko/20100720 Fedora/3.0.6-1.fc12 Thunderbird/3.0.6 MIME-Version: 1.0 To: Andrew Morton CC: "Paul E. McKenney" , Tejun Heo , Oleg Nesterov , Linux Kernel Mailing List Subject: Re: [PATCH] pidns: Make pid_max per namespace References: <4D6F53B5.5090105@parallels.com> <20110307155823.22e47d73.akpm@linux-foundation.org> In-Reply-To: <20110307155823.22e47d73.akpm@linux-foundation.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1443 Lines: 37 On 03/08/2011 02:58 AM, Andrew Morton wrote: > On Thu, 03 Mar 2011 11:39:17 +0300 > Pavel Emelyanov wrote: > >> Rationale: >> >> On x86_64 with big ram people running containers set pid_max on host to >> large values to be able to launch more containers. At the same time >> containers running 32-bit software experience problems with large pids - ps >> calls readdir/stat on proc entries and inode's i_ino happen to be too big >> for the 32-bit API. >> >> Thus, the ability to limit the pid value inside container is required. >> > > This is a behavioural change, isn't it? In current kernels a write to > /proc/sys/kernel/pid_max will change the max pid on all processes. > After this change, that write will only affect processes in the current > namespace. Anyone who was depending on the old behaviour might run > into problems? Hardly. If the behavior of some two apps depends on its synchronous change, these two might want to run in the same pid namespace. > Also: documentation. Documentation/sysctl/kernel.txt would like an > update. And perhaps also the pidns documentation which we forgot to > create :( OK, I'll fix the existing docs. Thanks, Pavel -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/