Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753169Ab0DZMrf (ORCPT ); Mon, 26 Apr 2010 08:47:35 -0400 Received: from rcsinet10.oracle.com ([148.87.113.121]:55001 "EHLO rcsinet10.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752621Ab0DZMrd convert rfc822-to-8bit (ORCPT ); Mon, 26 Apr 2010 08:47:33 -0400 MIME-Version: 1.0 Message-ID: Date: Mon, 26 Apr 2010 05:45:57 -0700 (PDT) From: Dan Magenheimer To: Avi Kivity Cc: 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: <20100422134249.GA2963@ca-server1.us.oracle.com> <4BD06B31.9050306@redhat.com> <53c81c97-b30f-4081-91a1-7cef1879c6fa@default> <4BD07594.9080905@redhat.com> <4BD16D09.2030803@redhat.com> <4BD1A74A.2050003@redhat.com> <4830bd20-77b7-46c8-994b-8b4fa9a79d27@default> <4BD1B427.9010905@redhat.com> <4BD336CF.1000103@redhat.com> <4BD43182.1040508@redhat.com> <4BD44E74.2020506@redhat.com> <7264e3c0-15fe-4b70-a3d8-2c36a2b934df@default 4BD52C4F.40505@redhat.com> In-Reply-To: <4BD52C4F.40505@redhat.com> X-Priority: 3 X-Mailer: Oracle Beehive Extensions for Outlook 1.5.1.5.2 (401224) [OL 12.0.6514.5000] Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT X-Auth-Type: Internal IP X-Source-IP: acsinet15.oracle.com [141.146.126.227] X-CT-RefId: str=0001.0A090201.4BD58B4A.00C0:SCFMA922111,ss=1,fgs=0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 739 Lines: 18 > dma engines are present on commodity hardware now: > > http://en.wikipedia.org/wiki/I/O_Acceleration_Technology > > I don't know if consumer machines have them, but servers certainly do. > modprobe ioatdma. They don't seem to have gained much ground in the FIVE YEARS since the patch was first posted to Linux, have they? Maybe it's because memory-to-memory copy using a CPU is so fast (especially for page-ish quantities of data) and is a small percentage of CPU utilization these days? -- 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/