From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Sun, 16 Nov 2008 16:38:56 +0900 (JST) From: KOSAKI Motohiro Subject: Re: [PATCH -mm] vmscan: bail out of page reclaim after swap_cluster_max pages In-Reply-To: <20081113171208.6985638e@bree.surriel.com> References: <20081113171208.6985638e@bree.surriel.com> Message-Id: <20081116163316.F205.KOSAKI.MOTOHIRO@jp.fujitsu.com> MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Rik van Riel , Balbir Singh Cc: kosaki.motohiro@jp.fujitsu.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org List-ID: One more point. > Sometimes the VM spends the first few priority rounds rotating back > referenced pages and submitting IO. Once we get to a lower priority, > sometimes the VM ends up freeing way too many pages. > > The fix is relatively simple: in shrink_zone() we can check how many > pages we have already freed and break out of the loop. > > However, in order to do this we do need to know how many pages we already > freed, so move nr_reclaimed into scan_control. IIRC, Balbir-san explained the implemetation of the memcgroup force cache dropping feature need non bail out at the past reclaim throttring discussion. I am not sure about this still right or not (iirc, memcgroup implemetation was largely changed). Balbir-san, Could you comment to this patch? -- 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