Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760983Ab2FHDDc (ORCPT ); Thu, 7 Jun 2012 23:03:32 -0400 Received: from e35.co.us.ibm.com ([32.97.110.153]:41955 "EHLO e35.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752883Ab2FHDD2 (ORCPT ); Thu, 7 Jun 2012 23:03:28 -0400 Message-ID: <4FD16B6E.8000307@linaro.org> Date: Thu, 07 Jun 2012 20:03:10 -0700 From: John Stultz User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:12.0) Gecko/20120430 Thunderbird/12.0.1 MIME-Version: 1.0 To: Dave Hansen CC: Dmitry Adamushko , KOSAKI Motohiro , LKML , Andrew Morton , Android Kernel Team , Robert Love , Mel Gorman , Hugh Dickins , Rik van Riel , Dave Chinner , Neil Brown , Andrea Righi , "Aneesh Kumar K.V" , Taras Glek , Mike Hommey , Jan Kara Subject: Re: [PATCH 3/3] [RFC] tmpfs: Add FALLOC_FL_MARK_VOLATILE/UNMARK_VOLATILE handlers References: <1338575387-26972-1-git-send-email-john.stultz@linaro.org> <1338575387-26972-4-git-send-email-john.stultz@linaro.org> <4FC9235F.5000402@gmail.com> <4FC92E30.4000906@linaro.org> <4FC9360B.4020401@gmail.com> <4FC937AD.8040201@linaro.org> <4FC9438B.1000403@gmail.com> <4FC94F61.20305@linaro.org> <4FCFB4F6.6070308@gmail.com> <4FCFEE36.3010902@linaro.org> <4FD13C30.2030401@linux.vnet.ibm.com> In-Reply-To: <4FD13C30.2030401@linux.vnet.ibm.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-Content-Scanned: Fidelis XPS MAILER x-cbid: 12060803-6148-0000-0000-00000685654B Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1375 Lines: 34 On 06/07/2012 04:41 PM, Dave Hansen wrote: > On 06/07/2012 03:55 AM, Dmitry Adamushko wrote: >> but maybe we should also purge them before we swap out some non-tmpfs >> pages or drop some file-backed pages? > > Sure... I guess we could kick that from either direct reclaim or from > kswapd. But, then we're basically back to the places where > shrink_slab() is called. > > I think that means that we think it's preferable to integrate this more > directly in the VM instead of sticking it off in the corner of tmpfs > only, or pretending it's a slab. > > Dunno... The slab shrinker one isn't looking _so_ bad at the moment. Dave also pointed out to me on irc that on a system without swap, shmem_writepage doesn't even get called, which kills the utility of triggering volatile purging from writepage. So I'm falling back to using a shrinker for now, but I think Dmitry's point is an interesting one, and am interested in finding a better place to trigger purging volatile ranges from the mm code. If anyone has any suggestions, let me know, otherwise I'll go back to trying to better grok the mm code. thanks -john -- 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/