Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932095Ab0HaDqz (ORCPT ); Mon, 30 Aug 2010 23:46:55 -0400 Received: from mail-iw0-f174.google.com ([209.85.214.174]:48421 "EHLO mail-iw0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932073Ab0HaDqy (ORCPT ); Mon, 30 Aug 2010 23:46:54 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; b=T8UUQpk1ZZngFP2inHHEpL6eBAOoZMs2Mlth8hGZzJZAQm0LvRLugNT/EAbR0fvKBR hQpnfq/UpFALbVoyxVtqS165O5nfTDlgdTVpeV0lQXHk+PVoUSAv2keewuYBtkqB4hlH qNKfhSK4KavqIPMhNbv/BCXyhHRevhU9Bsu+w= MIME-Version: 1.0 In-Reply-To: <4C7C6959.3030801@redhat.com> References: <20100831095140.87C7.A69D9226@jp.fujitsu.com> <4C7C6959.3030801@redhat.com> Date: Tue, 31 Aug 2010 12:46:53 +0900 Message-ID: Subject: Re: [PATCH] vmscan: prevent background aging of anon page in no swap system From: Minchan Kim To: Rik van Riel Cc: KOSAKI Motohiro , Ying Han , Andrew Morton , linux-mm , LKML , Venkatesh Pallipadi , Johannes Weiner Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1524 Lines: 39 On Tue, Aug 31, 2010 at 11:30 AM, Rik van Riel wrote: > On 08/30/2010 09:23 PM, Minchan Kim wrote: > >> Ying's one and mine both has a same effect. >> Only difference happens swap is full. My version maintains old >> behavior but Ying's one changes the behavior. I admit swap full is >> rare event but I hoped not changed old behavior if we doesn't find any >> problem. >> If kswapd does aging when swap full happens, is it a problem? > > It may be a good thing, since swap will often be freed again > (when something is swapped in, or exits). > > Having some more anonymous pages sit on the inactive list > gives them a chance to get used again, potentially giving > us a better chance of preserving the working set when swap > is full or near full a lot of the time. Do you mean we would be better to do background aging when swap is full? I wanted it. So I used total_swap_pages to protect working set when swap is full. But Ying and KOSAKI's don't like it since it makes code inconsistent or not simply. And I agree it's rare event as KOSAKI mentioned. Hmm... What do you think about it? If you don't mind, I will resend latest version(use nr_swap_page usage and compile out inactive_anon_is_low in case of !CONFIG_SWAP). -- Kind regards, Minchan Kim -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/