From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4656F625.30402@redhat.com> Date: Fri, 25 May 2007 10:43:49 -0400 From: Rik van Riel MIME-Version: 1.0 Subject: Re: [patch 1/1] vmscan: give referenced, active and unmapped pages a second trip around the LRU References: <200705242357.l4ONvw49006681@shell0.pdx.osdl.net> In-Reply-To: <200705242357.l4ONvw49006681@shell0.pdx.osdl.net> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: akpm@linux-foundation.org Cc: linux-mm@kvack.org, mbligh@mbligh.org List-ID: akpm@linux-foundation.org wrote: > From: Andrew Morton > > Martin spotted this. > > In the original rmap conversion in 2.5.32 we broke aging of pagecache pages on > the active list: we deactivate these pages even if they had PG_referenced set. IIRC this is done to make sure that we reclaim page cache pages ahead of mapped anonymous pages. > We should instead clear PG_referenced and give these pages another trip around > the active list. A side effect of this is that the page will now need TWO references to be promoted back to the active list from the inactive list. The current code leaves PG_referenced set, so that the first access to a page cache page that was demoted to the inactive list will cause that page to be moved back to the active list. -- Politics is the struggle between those who want to make their country the best in the world, and those who believe it already is. Each group calls the other unpatriotic. -- 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