Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933792Ab0D3SXv (ORCPT ); Fri, 30 Apr 2010 14:23:51 -0400 Received: from mx1.redhat.com ([209.132.183.28]:45305 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933191Ab0D3RWb (ORCPT ); Fri, 30 Apr 2010 13:22:31 -0400 Message-ID: <4BD9D7A5.1070003@redhat.com> Date: Thu, 29 Apr 2010 22:01:57 +0300 From: Avi Kivity User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.9) Gecko/20100330 Fedora/3.0.4-1.fc12 Thunderbird/3.0.4 MIME-Version: 1.0 To: Dan Magenheimer CC: Pavel Machek , linux-kernel@vger.kernel.org, linux-mm@kvack.org, jeremy@goop.org, hugh.dickins@tiscali.co.uk, ngupta@vflare.org, JBeulich@novell.com, chris.mason@oracle.com, kurt.hackel@oracle.com, dave.mccracken@oracle.com, npiggin@suse.de, akpm@linux-foundation.org, riel@redhat.com Subject: Re: Frontswap [PATCH 0/4] (was Transcendent Memory): overview References: <4BD16D09.2030803@redhat.com> <4BD1A74A.2050003@redhat.com> <4830bd20-77b7-46c8-994b-8b4fa9a79d27@default> <4BD1B427.9010905@redhat.com> <4BD1B626.7020702@redhat.com> <5fa93086-b0d7-4603-bdeb-1d6bfca0cd08@default> <4BD3377E.6010303@redhat.com> <1c02a94a-a6aa-4cbb-a2e6-9d4647760e91@default4BD43033.7090706@redhat.com> <4BD9D702.90209@redhat.com> In-Reply-To: <4BD9D702.90209@redhat.com> 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: 878 Lines: 21 On 04/29/2010 09:59 PM, Avi Kivity wrote: > > I'm convinced it's useful. The API is so close to a block device > (read/write with key/value vs read/write with sector/value) that we > should make the effort not to introduce a new API. > Plus of course the asynchronity and batching of the block layer. Even if you don't use a dma engine, you improve performance by exiting one per several dozen pages instead of for every page, perhaps enough to allow the hypervisor to justify copying the memory with non-temporal moves. -- I have a truly marvellous patch that fixes the bug which this signature is too narrow to contain. -- 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/