From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760081AbZEKVoa (ORCPT ); Mon, 11 May 2009 17:44:30 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756510AbZEKVoT (ORCPT ); Mon, 11 May 2009 17:44:19 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:55731 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759395AbZEKVoS (ORCPT ); Mon, 11 May 2009 17:44:18 -0400 Date: Mon, 11 May 2009 14:39:06 -0700 From: Andrew Morton To: David Rientjes Cc: gregkh@suse.de, npiggin@suse.de, mel@csn.ul.ie, a.p.ziljstra@chello.nl, cl@linux-foundation.org, dave@linux.vnet.ibm.com, san@android.com, arve@android.com, linux-kernel@vger.kernel.org Subject: Re: [patch 10/11 -mmotm] oom: avoid oom kill if no interruptible tasks Message-Id: <20090511143906.1cde5f6e.akpm@linux-foundation.org> In-Reply-To: References: X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.20; i486-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 10 May 2009 15:07:25 -0700 (PDT) David Rientjes wrote: > If there are no interruptible system tasks other than kthreads, It's unclear what the term "system task" means. Just "task"? > no task > should be chosen for oom kill since they won't respond to the SIGKILL > anyway. Instead, we choose to simply fail page allocations if reclaim > cannot free memory and hope for the best. But plain old user processes enter and leave D state all the time. The task may well just be sitting there waiting for a disk read to complete. It will respond to the SIGKILL shortly after the IO completes, so an appropriate action here is to just wait for that to happen.