From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S265025AbUGGIjW (ORCPT ); Wed, 7 Jul 2004 04:39:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S264991AbUGGIh7 (ORCPT ); Wed, 7 Jul 2004 04:37:59 -0400 Received: from outmx012.isp.belgacom.be ([195.238.3.70]:4488 "EHLO outmx012.isp.belgacom.be") by vger.kernel.org with ESMTP id S265006AbUGGIcG (ORCPT ); Wed, 7 Jul 2004 04:32:06 -0400 Subject: Re: VM - is "reserved memory for root" possible (in case of a leak)? From: FabF To: Tomasz Chmielewski Cc: linux-kernel@vger.kernel.org In-Reply-To: <40EBA846.6010705@interia.pl> References: <40EBA846.6010705@interia.pl> Content-Type: text/plain Message-Id: <1089189121.3692.5.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.6 (1.4.6-2) Date: Wed, 07 Jul 2004 10:32:02 +0200 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 2004-07-07 at 09:37, Tomasz Chmielewski wrote: > Hello, > > Short nature of a problem: > > Recently I was playing with Apache2 as a proxy + mod_clamav as a virus > scanner, put some load to it, and in a short time hanged the machine > (actually, it was short of memory, and it stopped to respond - in logs I > saw VM was killing some other processes, unfortunately not Apache). > > As I could reach the machine only remotely, it was no wonder I run into > troubles... > > Sounds familiar? > > > Solution? > > I was thinking, if there is something like: > > "reserved_min_memory_for_root = 10M" > "reserved_min_memory_processes = /usr/sbin/sshd, /usr/sbin/pppd, etc.etc" > > Which would just give that memory for those processes "once and for > all", and thus, saving trouble in case of a memory leak, uncontrolled > process, or similar. > > I know it would be tricky to implement it, because the question arises, > what happens if we have no memory left, and these > "reserved_min_memory_processes" begin to grow? > > But I think it would be something like a comparison: > > ulimit vs this "reserved_min_memory_for_root", and > quota vs -m option from mke2fs. > > Is there something like it already in the kernel? > > > It would be similar to mke2fs for the filesystem: > > # man mke2fs > > -m reserved-blocks-percentage > Specify the percentage of the filesystem blocks reserved > for the > super-user. This value defaults to 5% Hi Tomasz, Maybe you would want to tune /proc/sys/vm/min_free_kbytes or renice +xx apache.Some vmstat 1 report, uname -a could be interesting as well.There's no per profile VM granularity in 2.6. Regards, FabF > > > > Regards, > > Tomasz Chmielewski > > - > 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/ >