From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail137.messagelabs.com (mail137.messagelabs.com [216.82.249.19]) by kanga.kvack.org (Postfix) with SMTP id 088FF8D0039 for ; Mon, 28 Feb 2011 00:48:57 -0500 (EST) Date: Mon, 28 Feb 2011 06:48:18 +0100 From: Andrea Arcangeli Subject: Re: [PATCH 2/2] mm: compaction: Minimise the time IRQs are disabled while isolating pages for migration Message-ID: <20110228054818.GF22700@random.random> References: <1298664299-10270-1-git-send-email-mel@csn.ul.ie> <1298664299-10270-3-git-send-email-mel@csn.ul.ie> <20110228111746.34f3f3e0.kamezawa.hiroyu@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110228111746.34f3f3e0.kamezawa.hiroyu@jp.fujitsu.com> Sender: owner-linux-mm@kvack.org List-ID: To: KAMEZAWA Hiroyuki Cc: Mel Gorman , Andrew Morton , Arthur Marsh , Clemens Ladisch , Linux-MM , Linux Kernel Mailing List On Mon, Feb 28, 2011 at 11:17:46AM +0900, KAMEZAWA Hiroyuki wrote: > BTW, I forget why we always take zone->lru_lock with IRQ disabled.... To decrease lock contention in SMP to deliver overall better performance (not sure how much it helps though). It was supposed to be hold for a very short time (PAGEVEC_SIZE) to avoid giving irq latency problems. -- 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