From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753819Ab0EUD0W (ORCPT ); Thu, 20 May 2010 23:26:22 -0400 Received: from mail-wy0-f174.google.com ([74.125.82.174]:47742 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752889Ab0EUD0V (ORCPT ); Thu, 20 May 2010 23:26:21 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:cc:in-reply-to:references:content-type:date :message-id:mime-version:x-mailer:content-transfer-encoding; b=oWMiw4uSBAIKlBhzSdn+dH39Xy34oX0Mjrz58lFN6zK0nuaf/VsS5t1nxVqFdIPonW rTqlOgMkrLEvPH/etE4zjsh2QGTUb8oCs3JFBrWCLUh7UILRWOBYLSoDRpucBnYMlCUY f5NZR/MgxsgLUXpNCbWTrXh9L6zhwwmhkmIs4= Subject: Re: Transparent Hugepage Support #25 From: Eric Dumazet To: Andrea Arcangeli Cc: linux-mm@kvack.org, Andrew Morton , linux-kernel@vger.kernel.org, Marcelo Tosatti , Adam Litke , Avi Kivity , Izik Eidus , Hugh Dickins , Nick Piggin , Rik van Riel , Mel Gorman , Dave Hansen , Benjamin Herrenschmidt , Ingo Molnar , Mike Travis , KAMEZAWA Hiroyuki , Christoph Lameter , Chris Wright , bpicco@redhat.com, KOSAKI Motohiro , Balbir Singh , "Michael S. Tsirkin" , Peter Zijlstra , Johannes Weiner , Daisuke Nishimura , Chris Mason , Borislav Petkov In-Reply-To: <20100521000539.GA5733@random.random> References: <20100521000539.GA5733@random.random> Content-Type: text/plain; charset="UTF-8" Date: Fri, 21 May 2010 05:26:13 +0200 Message-ID: <1274412373.4977.8.camel@edumazet-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Le vendredi 21 mai 2010 à 02:05 +0200, Andrea Arcangeli a écrit : > If you're running scientific applications, JVM or large gcc builds > (see attached patch for gcc), and you want to run from 2.5% faster for > kernel build (on bare metal), or 8% faster in translate.o of qemu (on > bare metal), 15% faster or more with virt and Intel EPT/ AMD NPT > (depending on the workload), you should apply and run the transparent > hugepage support on your systems. > > Awesome results have already been posted on lkml, if you test and > benchmark it, please provide any positive/negative real-life result on > lkml (or privately to me if you prefer). The more testing the better. > Interesting ! Did you tried to change alloc_large_system_hash() to use hugepages for very large allocations ? We currently use vmalloc() on NUMA machines... Dentry cache hash table entries: 2097152 (order: 12, 16777216 bytes) Inode-cache hash table entries: 1048576 (order: 11, 8388608 bytes) IP route cache hash table entries: 524288 (order: 10, 4194304 bytes) TCP established hash table entries: 524288 (order: 11, 8388608 bytes) 0xffffc90000003000-0xffffc90001004000 16781312 alloc_large_system_hash+0x1d8/0x280 pages=4096 vmalloc vpages N0=2048 N1=2048 0xffffc9000100f000-0xffffc90001810000 8392704 alloc_large_system_hash+0x1d8/0x280 pages=2048 vmalloc vpages N0=1024 N1=1024 0xffffc90005882000-0xffffc90005c83000 4198400 alloc_large_system_hash+0x1d8/0x280 pages=1024 vmalloc vpages N0=512 N1=512 0xffffc90005c84000-0xffffc90006485000 8392704 alloc_large_system_hash+0x1d8/0x280 pages=2048 vmalloc vpages N0=1024 N1=1024