From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754038Ab0CWT7v (ORCPT ); Tue, 23 Mar 2010 15:59:51 -0400 Received: from smtp1.linux-foundation.org ([140.211.169.13]:52284 "EHLO smtp1.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753815Ab0CWT7t (ORCPT ); Tue, 23 Mar 2010 15:59:49 -0400 Date: Tue, 23 Mar 2010 12:54:47 -0700 (PDT) From: Linus Torvalds To: Anton Starikov cc: Ingo Molnar , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, bugzilla-daemon@bugzilla.kernel.org, bugme-daemon@bugzilla.kernel.org, Peter Zijlstra Subject: Re: [Bugme-new] [Bug 15618] New: 2.6.18->2.6.32->2.6.33 huge regression in performance In-Reply-To: <9D040E9A-80F2-468F-A6CD-A4912615CD3F@gmail.com> Message-ID: References: <20100323102208.512c16cc.akpm@linux-foundation.org> <20100323173409.GA24845@elte.hu> <9D040E9A-80F2-468F-A6CD-A4912615CD3F@gmail.com> User-Agent: Alpine 2.00 (LFD 1167 2008-08-23) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 23 Mar 2010, Anton Starikov wrote: > > On Mar 23, 2010, at 6:45 PM, Linus Torvalds wrote: > > > > > > > On Tue, 23 Mar 2010, Ingo Molnar wrote: > >> > >> It shows a very brutal amount of page fault invoked mmap_sem spinning > >> overhead. > > > > Isn't this already fixed? It's the same old "x86-64 rwsemaphores are using > > the shit-for-brains generic version" thing, and it's fixed by > > > > 1838ef1 x86-64, rwsem: 64-bit xadd rwsem implementation > > 5d0b723 x86: clean up rwsem type system > > 59c33fa x86-32: clean up rwsem inline asm statements > > > > NOTE! None of those are in 2.6.33 - they were merged afterwards. But they > > are in 2.6.34-rc1 (and obviously current -git). So Anton would have to > > compile his own kernel to test his load. > > > Applied mentioned patches. Things didn't improve too much. Yeah, I missed at least one commit, namely bafaecd x86-64: support native xadd rwsem implementation which is the one that actually makes x86-64 able to use the xadd version. Linus From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail203.messagelabs.com (mail203.messagelabs.com [216.82.254.243]) by kanga.kvack.org (Postfix) with ESMTP id D4B4F6B01CC for ; Tue, 23 Mar 2010 15:59:53 -0400 (EDT) Date: Tue, 23 Mar 2010 12:54:47 -0700 (PDT) From: Linus Torvalds Subject: Re: [Bugme-new] [Bug 15618] New: 2.6.18->2.6.32->2.6.33 huge regression in performance In-Reply-To: <9D040E9A-80F2-468F-A6CD-A4912615CD3F@gmail.com> Message-ID: References: <20100323102208.512c16cc.akpm@linux-foundation.org> <20100323173409.GA24845@elte.hu> <9D040E9A-80F2-468F-A6CD-A4912615CD3F@gmail.com> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-linux-mm@kvack.org To: Anton Starikov Cc: Ingo Molnar , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, bugzilla-daemon@bugzilla.kernel.org, bugme-daemon@bugzilla.kernel.org, Peter Zijlstra List-ID: On Tue, 23 Mar 2010, Anton Starikov wrote: > > On Mar 23, 2010, at 6:45 PM, Linus Torvalds wrote: > > > > > > > On Tue, 23 Mar 2010, Ingo Molnar wrote: > >> > >> It shows a very brutal amount of page fault invoked mmap_sem spinning > >> overhead. > > > > Isn't this already fixed? It's the same old "x86-64 rwsemaphores are using > > the shit-for-brains generic version" thing, and it's fixed by > > > > 1838ef1 x86-64, rwsem: 64-bit xadd rwsem implementation > > 5d0b723 x86: clean up rwsem type system > > 59c33fa x86-32: clean up rwsem inline asm statements > > > > NOTE! None of those are in 2.6.33 - they were merged afterwards. But they > > are in 2.6.34-rc1 (and obviously current -git). So Anton would have to > > compile his own kernel to test his load. > > > Applied mentioned patches. Things didn't improve too much. Yeah, I missed at least one commit, namely bafaecd x86-64: support native xadd rwsem implementation which is the one that actually makes x86-64 able to use the xadd version. Linus -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org