From mboxrd@z Thu Jan 1 00:00:00 1970 Date: Thu, 8 Feb 2007 14:03:38 -0800 From: Andrew Morton Subject: Re: Drop PageReclaim() Message-Id: <20070208140338.971b3f53.akpm@linux-foundation.org> In-Reply-To: References: Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Christoph Lameter Cc: Hugh Dickins , linux-mm@kvack.org List-ID: On Thu, 8 Feb 2007 13:55:22 -0800 (PST) Christoph Lameter wrote: > Oh gosh. I hope I finally got my head around this. The page is taken off > the LRU for writeback then PageReclaim is set and its put back to the > inactive list when writeback ends. This is different from regular file > writeback where we leave the page on the LRU. > No, the page remains on the LRU while it's under writeback. It goes like this: During the vmscan we encounter a page at the tail of the inactive list which we want to reclaim, but it's dirty. So we start writeout and then move it to the head of the inactive list and keep scanning. When writeback completes, we take a look at the page to see if it still seems to be reclaimable and if so, move it to the tail of the inactive list so that it will be reclaimed very soon. PG_reclaim is used to indicate pages which need this treatment. -- 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