From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759543AbXJDTkL (ORCPT ); Thu, 4 Oct 2007 15:40:11 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756023AbXJDTj6 (ORCPT ); Thu, 4 Oct 2007 15:39:58 -0400 Received: from mx1.redhat.com ([66.187.233.31]:45875 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755796AbXJDTj5 (ORCPT ); Thu, 4 Oct 2007 15:39:57 -0400 Date: Thu, 4 Oct 2007 15:39:40 -0400 From: Rik van Riel To: Christoph Lameter Cc: Andi Kleen , akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, travis@sgi.com Subject: Re: [13/18] x86_64: Allow fallback for the stack Message-ID: <20071004153940.49bd5afc@bree.surriel.com> In-Reply-To: References: <20071004035935.042951211@sgi.com> <20071004040004.708466159@sgi.com> <200710041356.51750.ak@suse.de> Organization: Red Hat, Inc. X-Mailer: Claws Mail 2.9.1 (GTK+ 2.10.4; 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 On Thu, 4 Oct 2007 12:20:50 -0700 (PDT) Christoph Lameter wrote: > On Thu, 4 Oct 2007, Andi Kleen wrote: > > > We've known for ages that it is possible. But it has been always so > > rare that it was ignored. > > Well we can now address the rarity. That is the whole point of the > patchset. Introducing complexity to fight a very rare problem with a good fallback (refusing to fork more tasks, as well as lumpy reclaim) somehow does not seem like a good tradeoff. > > Is there any evidence this is more common now than it used to be? > > It will be more common if the stack size is increased beyond 8k. Why would we want to do such a thing? 8kB stacks are large enough... -- "Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it." - Brian W. Kernighan From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 4 Oct 2007 15:39:40 -0400 From: Rik van Riel Subject: Re: [13/18] x86_64: Allow fallback for the stack Message-ID: <20071004153940.49bd5afc@bree.surriel.com> In-Reply-To: References: <20071004035935.042951211@sgi.com> <20071004040004.708466159@sgi.com> <200710041356.51750.ak@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: Andi Kleen , akpm@linux-foundation.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, travis@sgi.com List-ID: On Thu, 4 Oct 2007 12:20:50 -0700 (PDT) Christoph Lameter wrote: > On Thu, 4 Oct 2007, Andi Kleen wrote: > > > We've known for ages that it is possible. But it has been always so > > rare that it was ignored. > > Well we can now address the rarity. That is the whole point of the > patchset. Introducing complexity to fight a very rare problem with a good fallback (refusing to fork more tasks, as well as lumpy reclaim) somehow does not seem like a good tradeoff. > > Is there any evidence this is more common now than it used to be? > > It will be more common if the stack size is increased beyond 8k. Why would we want to do such a thing? 8kB stacks are large enough... -- "Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it." - Brian W. Kernighan -- 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/ . Don't email: email@kvack.org