From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S967643AbWK2U5R (ORCPT ); Wed, 29 Nov 2006 15:57:17 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S967673AbWK2U5R (ORCPT ); Wed, 29 Nov 2006 15:57:17 -0500 Received: from outpipe-village-512-1.bc.nu ([81.2.110.250]:13456 "EHLO lxorguk.ukuu.org.uk") by vger.kernel.org with ESMTP id S967643AbWK2U5Q (ORCPT ); Wed, 29 Nov 2006 15:57:16 -0500 Date: Wed, 29 Nov 2006 21:04:08 +0000 From: Alan To: "Kunal Trivedi" Cc: linux-kernel@vger.kernel.org Subject: Re: Possible Bug in VM accounting (Committed_AS) on x86_64 architecture ? Message-ID: <20061129210408.3ea5800a@localhost.localdomain> In-Reply-To: <63a95c50611291129q109abeb2o7e5afb7ca94a3f2c@mail.gmail.com> References: <63a95c50611291122l27c9af6fha78db3bf32fe6c1c@mail.gmail.com> <63a95c50611291129q109abeb2o7e5afb7ca94a3f2c@mail.gmail.com> X-Mailer: Sylpheed-Claws 2.6.0 (GTK+ 2.8.20; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org > I have noticed that 64 bit machine with overcommit policy (as above) > starts giving problem within 3-4 weeks. To prove that I've written > small program. The older RHEL kernels had some cases that didn't quite account exactly but current ones ought to be right - for Centos I'd expect similar but ask there not here as it is a very old and branched away kernel. > It allocates memory of different sizes (not that it matters much due > to caching of diffeent malloc. I am using standard ptmalloc). Sizes > are 16B, 32B, 64B, 256B, 1024B, 57B, 127B and so on... . Then it > touches that memory (memset) and then free it. These operations are > being performed in while(1) loop. I would expect that, it's fragmentation. The real test is whether the values go back properly when you kill the program.