From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail191.messagelabs.com (mail191.messagelabs.com [216.82.242.19]) by kanga.kvack.org (Postfix) with ESMTP id 28C958D0040 for ; Wed, 23 Mar 2011 23:09:21 -0400 (EDT) Date: Wed, 23 Mar 2011 20:04:58 -0700 From: Andrew Morton Subject: Re: [PATCH 1/5] vmscan: remove all_unreclaimable check from direct reclaim path completely Message-Id: <20110323200458.724f2af8.akpm@linux-foundation.org> In-Reply-To: <20110324114842.CC70.A69D9226@jp.fujitsu.com> References: <20110324111200.1AF4.A69D9226@jp.fujitsu.com> <20110323192150.9895afe3.akpm@linux-foundation.org> <20110324114842.CC70.A69D9226@jp.fujitsu.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: KOSAKI Motohiro Cc: Minchan Kim , linux-kernel@vger.kernel.org, David Rientjes , Linus Torvalds , Rik van Riel , Oleg Nesterov , linux-mm , Andrey Vagin , Hugh Dickins , KAMEZAWA Hiroyuki , Nick Piggin , Johannes Weiner On Thu, 24 Mar 2011 11:48:19 +0900 (JST) KOSAKI Motohiro wrote: > > On Thu, 24 Mar 2011 11:11:46 +0900 (JST) KOSAKI Motohiro wrote: > > > > > Subject: [PATCH] vmscan: remove all_unreclaimable check from direct reclaim path completely > > > > zone.all_unreclaimable is there to prevent reclaim from wasting CPU > > cycles scanning a zone which has no reclaimable pages. When originally > > implemented it did this very well. > > > > That you guys keep breaking it, or don't feel like improving it is not a > > reason to remove it! > > > > If the code is unneeded and the kernel now reliably solves this problem > > by other means then this should have been fully explained in the > > changelog, but it was not even mentioned. > > The changelog says, the logic was removed at 2008. three years ago. > even though it's unintentionally. and I and minchan tried to resurrect > the broken logic and resurrected a bug in the logic too. then, we > are discussed it should die or alive. > > Which part is hard to understand for you? > The part which isn't there: how does the kernel now address the problem which that code fixed? -- 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