From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail144.messagelabs.com (mail144.messagelabs.com [216.82.254.51]) by kanga.kvack.org (Postfix) with SMTP id 0E4136B012F for ; Mon, 20 Jun 2011 23:15:15 -0400 (EDT) Message-ID: <4E000CB5.3050201@redhat.com> Date: Tue, 21 Jun 2011 11:15:01 +0800 From: Cong Wang MIME-Version: 1.0 Subject: Re: [PATCH 1/3] mm: completely disable THP by transparent_hugepage=never References: <1308587683-2555-1-git-send-email-amwang@redhat.com> <20110620165035.GE20843@redhat.com> <4DFF7CDD.308@redhat.com> <20110620194321.GI20843@redhat.com> In-Reply-To: <20110620194321.GI20843@redhat.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Sender: owner-linux-mm@kvack.org List-ID: To: Andrea Arcangeli Cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org, Rik van Riel , Johannes Weiner , KAMEZAWA Hiroyuki , linux-mm@kvack.org ao? 2011a1'06ae??21ae?JPY 03:43, Andrea Arcangeli a??e??: > On Tue, Jun 21, 2011 at 01:01:17AM +0800, Cong Wang wrote: >> Without this patch, THP is still initialized (although khugepaged is not started), >> that is what I don't want to see when I pass "transparent_hugepage=never", >> because "never" for me means THP is totally unseen, even not initialized. > > The ram saving by not registering in sysfs is not worth the loss of > generic functionality. You can try to make the hash and slab > khugepaged allocations more dynamic if you want to microoptimize for > RAM usage, that I wouldn't be against if you find a way to do it > simply and without much complexity (and .text) added. But likely there > are other places to optimize that may introduce less tricks and would > give you a bigger saving than ~8kbytes, it's up to you. But the THP functionality is not going to be used. Yeah, sounds reasonable, I will try to check if I can make it. Thanks for pointing this out! -- 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