From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S261186AbVFDC3G (ORCPT ); Fri, 3 Jun 2005 22:29:06 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S261226AbVFDC3G (ORCPT ); Fri, 3 Jun 2005 22:29:06 -0400 Received: from smtp205.mail.sc5.yahoo.com ([216.136.129.95]:52142 "HELO smtp205.mail.sc5.yahoo.com") by vger.kernel.org with SMTP id S261186AbVFDC3C (ORCPT ); Fri, 3 Jun 2005 22:29:02 -0400 Message-ID: <42A111DF.8070806@yahoo.com.au> Date: Sat, 04 Jun 2005 12:28:47 +1000 From: Nick Piggin User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.7.6) Gecko/20050324 Debian/1.7.6-1 X-Accept-Language: en MIME-Version: 1.0 To: Subrahmanyam Ongole CC: William Lee Irwin III , linux-kernel@vger.kernel.org Subject: Re: x86-64: Kernel with large page size References: <20050604005930.GA31508@holomorphy.com> In-Reply-To: <20050604005930.GA31508@holomorphy.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org William Lee Irwin III wrote: > On Fri, Jun 03, 2005 at 05:50:55PM -0700, Subrahmanyam Ongole wrote: > >>When we run our application on AMD Opteron processors, we are seeing a >>large number of L1_AND_L2_DTLB_MISSES. We used oprofile to measure >>these numbers. [...] > > > PAGE_SIZE at the moment is intimately tied to the MMU's notions of > address translation, which are determined by hardware. > And even if we were able to increase the PAGE_SIZE that the kernel uses, this wouldn't really help your TLB misses. You may be able to use "huge pages" for your workload, which can use the 2/4MB pages. There is some good documentation for it in Documentation/vm/ (and probably on the web). -- SUSE Labs, Novell Inc. Send instant messages to your online friends http://au.messenger.yahoo.com