Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752748Ab3JHCvW (ORCPT ); Mon, 7 Oct 2013 22:51:22 -0400 Received: from mail-qc0-f181.google.com ([209.85.216.181]:49622 "EHLO mail-qc0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751806Ab3JHCvU (ORCPT ); Mon, 7 Oct 2013 22:51:20 -0400 Message-ID: <52537326.7000505@gmail.com> Date: Mon, 07 Oct 2013 22:51:18 -0400 From: KOSAKI Motohiro User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:17.0) Gecko/20130801 Thunderbird/17.0.8 MIME-Version: 1.0 To: Minchan Kim CC: "H. Peter Anvin" , John Stultz , LKML , Andrew Morton , Android Kernel Team , Robert Love , Mel Gorman , Hugh Dickins , Dave Hansen , Rik van Riel , Dmitry Adamushko , Dave Chinner , Neil Brown , Andrea Righi , Andrea Arcangeli , "Aneesh Kumar K.V" , Mike Hommey , Taras Glek , Dhaval Giani , Jan Kara , KOSAKI Motohiro , Michel Lespinasse , Rob Clark , "linux-mm@kvack.org" Subject: Re: [PATCH 05/14] vrange: Add new vrange(2) system call References: <1380761503-14509-6-git-send-email-john.stultz@linaro.org> <52533C12.9090007@zytor.com> <5253404D.2030503@linaro.org> <52534331.2060402@zytor.com> <52534692.7010400@linaro.org> <525347BE.7040606@zytor.com> <525349AE.1070904@linaro.org> <52534AEC.5040403@zytor.com> <20131008001306.GD25780@bbox> <52535EE1.3060700@zytor.com> <20131008020847.GH25780@bbox> In-Reply-To: <20131008020847.GH25780@bbox> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 933 Lines: 19 > Maybe, int madvise5(addr, length, MADV_DONTNEED|MADV_LAZY|MADV_SIGBUS, > &purged, &ret); > > Another reason to make it hard is that madvise(2) is tight coupled with > with vmas split/merge. It needs mmap_sem's write-side lock and it hurt > anon-vrange test performance much heavily and userland might want to > make volatile range with small unit like "page size" so it's undesireable > to make it with vma. Then, we should filter out to avoid vma split/merge > in implementation if only MADV_LAZY case? Doable but it could make code > complicated and lost consistency with other variant of madvise. I haven't seen your performance test result. Could please point out URLs? -- 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/