From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail138.messagelabs.com (mail138.messagelabs.com [216.82.249.35]) by kanga.kvack.org (Postfix) with ESMTP id 0F4866B0173 for ; Tue, 23 Aug 2011 16:18:19 -0400 (EDT) Received: from wpaz33.hot.corp.google.com (wpaz33.hot.corp.google.com [172.24.198.97]) by smtp-out.google.com with ESMTP id p7NKIICZ013193 for ; Tue, 23 Aug 2011 13:18:18 -0700 Received: from pzk6 (pzk6.prod.google.com [10.243.19.134]) by wpaz33.hot.corp.google.com with ESMTP id p7NKHwnM024712 (version=TLSv1/SSLv3 cipher=RC4-SHA bits=128 verify=NOT) for ; Tue, 23 Aug 2011 13:18:17 -0700 Received: by pzk6 with SMTP id 6so91010pzk.8 for ; Tue, 23 Aug 2011 13:18:16 -0700 (PDT) Date: Tue, 23 Aug 2011 13:18:14 -0700 (PDT) From: David Rientjes Subject: Re: [PATCH] oom: skip frozen tasks In-Reply-To: <20110823073101.6426.77745.stgit@zurg> Message-ID: References: <20110823073101.6426.77745.stgit@zurg> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org List-ID: To: Konstantin Khlebnikov Cc: linux-mm@kvack.org, Andrew Morton , linux-kernel@vger.kernel.org, KOSAKI Motohiro , Oleg Nesterov , KAMEZAWA Hiroyuki On Tue, 23 Aug 2011, Konstantin Khlebnikov wrote: > All frozen tasks are unkillable, and if one of them has TIF_MEMDIE > we must kill something else to avoid deadlock. After this patch > select_bad_process() will skip frozen task before checking TIF_MEMDIE. > The caveat is that if the task in the refrigerator is not OOM_DISABLE and there are no other eligible tasks (system wide, in the cpuset, or in the memcg) to kill, then the machine will panic as a result of this when, in the past, we would simply issue the SIGKILL and keep looping in the page allocator until it is thawed. So you may actually be trading a stall waiting for this thread to thaw for what would now be a panic, and that's not clearly better to me. -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org