From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wg0-f43.google.com (mail-wg0-f43.google.com [74.125.82.43]) by kanga.kvack.org (Postfix) with ESMTP id 27FAA6B0073 for ; Fri, 6 Feb 2015 13:40:35 -0500 (EST) Received: by mail-wg0-f43.google.com with SMTP id y19so15281931wgg.2 for ; Fri, 06 Feb 2015 10:40:34 -0800 (PST) Received: from mx1.redhat.com (mx1.redhat.com. [209.132.183.28]) by mx.google.com with ESMTPS id li1si5743070wjc.90.2015.02.06.10.40.32 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 06 Feb 2015 10:40:33 -0800 (PST) Message-ID: <54D50A87.8000902@redhat.com> Date: Fri, 06 Feb 2015 13:40:07 -0500 From: Rik van Riel MIME-Version: 1.0 Subject: Re: [PATCH v17 1/7] mm: support madvise(MADV_FREE) References: <20141130235652.GA10333@bbox> <20141202100125.GD27014@dhcp22.suse.cz> <20141203000026.GA30217@bbox> <20141203101329.GB23236@dhcp22.suse.cz> <20141205070816.GB3358@bbox> <20141205083249.GA2321@dhcp22.suse.cz> <54D0F9BC.4060306@gmail.com> <20150203234722.GB3583@blaptop> <20150206003311.GA2347@kernel.org> <20150206125825.GA4498@dhcp22.suse.cz> <20150206183242.GB2290@kernel.org> In-Reply-To: <20150206183242.GB2290@kernel.org> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Shaohua Li , Michal Hocko Cc: Minchan Kim , "Michael Kerrisk (man-pages)" , Andrew Morton , linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-api@vger.kernel.org, Hugh Dickins , Johannes Weiner , KOSAKI Motohiro , Mel Gorman , Jason Evans , zhangyanfei@cn.fujitsu.com, "Kirill A. Shutemov" , "Kirill A. Shutemov" -----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 02/06/2015 01:32 PM, Shaohua Li wrote: > On Fri, Feb 06, 2015 at 01:58:25PM +0100, Michal Hocko wrote: >> On Thu 05-02-15 16:33:11, Shaohua Li wrote: [...] >>> Did you think about move the MADV_FREE pages to the head of >>> inactive LRU, so they can be reclaimed easily? >> >> Yes this makes sense for pages living on the active LRU list. I >> would preserve LRU ordering on the inactive list because there is >> no good reason to make the operation more costly for inactive >> pages. On the other hand having tons of to-be-freed pages on the >> active list clearly sucks. Care to send a patch? > > Considering anon pages are in active LRU first, it's likely > MADV_FREE pages are in active list. I'm curious why preserves the > order of inactive list. Only before the first time MADV_FREE is called on those pages. If a program repeatedly allocates and frees the same memory region, not moving the MADV_FREE pages around in the LRU several times can save some overhead. - -- All rights reversed -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQEcBAEBAgAGBQJU1QqHAAoJEM553pKExN6DTXoH/3bS+VhdIm1EpOc8OOFtBHvd T63DHObtOY1FOog48CtgvUCfo7Q+g1aG/9hz7lJNP1G26B3+LNszM9OtE/9QrYUH uzmuWvFL7l0W0qen/WsyO0RcyqN+0mEXvNVqynTmJJu8qAG0p5WsjA6L5Penzj// tnBmn5xb1h3COjDZkHsxBfkpfCpNq5dm88K6B3nApHz4QhfcviKefczsrWdZ/bBc 2uMnlIebKY1Oq9MDHsg8p/b3lIHzwAf0xGSvGLN0YfzDPzlqBMbxSbVubYEA9EaU OiS1XqRp8okeGgrxsRAb/F8wPgClpce+h0E5xpyUuew2rlD1OmciX6iIDcE5Zrk= =KUng -----END PGP SIGNATURE----- -- 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