From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail6.bemta12.messagelabs.com (mail6.bemta12.messagelabs.com [216.82.250.247]) by kanga.kvack.org (Postfix) with ESMTP id E78D790016F for ; Wed, 22 Jun 2011 06:47:16 -0400 (EDT) Message-ID: <4E01C80F.8070605@redhat.com> Date: Wed, 22 Jun 2011 18:46:39 +0800 From: Cong Wang MIME-Version: 1.0 Subject: Re: [PATCH 2/3] mm: make the threshold of enabling THP configurable References: <1308587683-2555-1-git-send-email-amwang@redhat.com> <1308587683-2555-2-git-send-email-amwang@redhat.com> <20110620165955.GB9396@suse.de> <4DFF8050.9070201@redhat.com> <20110621093640.GD9396@suse.de> <4E015672.2020407@redhat.com> <20110622091611.GB7585@csn.ul.ie> In-Reply-To: <20110622091611.GB7585@csn.ul.ie> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: Mel Gorman Cc: Mel Gorman , linux-kernel@vger.kernel.org, akpm@linux-foundation.org, Andrea Arcangeli , Benjamin Herrenschmidt , Rik van Riel , Johannes Weiner , KAMEZAWA Hiroyuki , linux-mm@kvack.org ao? 2011a1'06ae??22ae?JPY 17:16, Mel Gorman a??e??: > > What I meant was that there is a rational reason why 512M is the > default for enabling THP by default. Tuning it lower than that by any > means makes very little sense. Tuning it higher might make some sense > but it is more likely that THP would simply be disabled via sysctl. I > see very little advantage to introducing this Kconfig option other > than as a source of confusion when running make oldconfig. > The tunable range is (512, 8192), so 512M is the minimum. Sure, I knew it can be disabled via /sys, actually we can do even more in user-space, that is totally move the 512M check out of kernel, why we didn't? In short, I think we should either remove the 512M from kernel, or make 512M to be tunable. Thanks. -- 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