From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail172.messagelabs.com (mail172.messagelabs.com [216.82.254.3]) by kanga.kvack.org (Postfix) with ESMTP id 51EE86B0071 for ; Tue, 23 Nov 2010 00:05:53 -0500 (EST) Date: Mon, 22 Nov 2010 21:01:32 -0800 From: Andrew Morton Subject: Re: [RFC 1/2] deactive invalidated pages Message-Id: <20101122210132.be9962c7.akpm@linux-foundation.org> In-Reply-To: References: <20101122141449.9de58a2c.akpm@linux-foundation.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org To: Minchan Kim Cc: linux-mm , LKML , Peter Zijlstra , Rik van Riel , KOSAKI Motohiro , Johannes Weiner , Nick Piggin List-ID: On Tue, 23 Nov 2010 13:52:05 +0900 Minchan Kim wrote: > >> +/* > >> + * Function used to forecefully demote a page to the head of the inactive > >> + * list. > >> + */ > > > > This comment is wrong? __The page gets moved to the _tail_ of the > > inactive list? > > No. I add it in _head_ of the inactive list intentionally. > Why I don't add it to _tail_ is that I don't want to be aggressive. > The page might be real working set. So I want to give a chance to > activate it again. Well.. why? The user just tried to toss the page away altogether. If the kernel wasn't able to do that immediately, the best it can do is to toss the page away asap? > If it's not working set, it can be reclaimed easily and it can prevent > active page demotion since inactive list size would be big enough for > not calling shrink_active_list. What is "working set"? Mapped and unmapped pagecache, or are you referring solely to mapped pagecache? If it's mapped pagecache then the user was being a bit silly (or didn't know that some other process had mapped the file). In which case we need to decide what to do - leave the page alone, deactivate it, or half-deactivate it as this patch does. -- 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 policy in Canada: sign http://dissolvethecrtc.ca/ Don't email: email@kvack.org