From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail143.messagelabs.com (mail143.messagelabs.com [216.82.254.35]) by kanga.kvack.org (Postfix) with SMTP id 5F4156B01B9 for ; Tue, 23 Mar 2010 16:44:00 -0400 (EDT) Received: by bwz19 with SMTP id 19so5584807bwz.6 for ; Tue, 23 Mar 2010 13:43:58 -0700 (PDT) Subject: Re: [Bugme-new] [Bug 15618] New: 2.6.18->2.6.32->2.6.33 huge regression in performance Mime-Version: 1.0 (Apple Message framework v1077) Content-Type: text/plain; charset=us-ascii From: Anton Starikov In-Reply-To: Date: Tue, 23 Mar 2010 21:43:54 +0100 Content-Transfer-Encoding: quoted-printable Message-Id: <9FC34DA1-D6DD-41E5-8B76-0712A813C549@gmail.com> References: <20100323102208.512c16cc.akpm@linux-foundation.org> <20100323173409.GA24845@elte.hu> <9D040E9A-80F2-468F-A6CD-A4912615CD3F@gmail.com> Sender: owner-linux-mm@kvack.org To: Linus Torvalds 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: I think we got a winner! Problem seems to be fixed. Just for record, I used next patches: 59c33fa7791e9948ba467c2b83e307a0d087ab49 5d0b7235d83eefdafda300656e97d368afcafc9a 1838ef1d782f7527e6defe87e180598622d2d071 4126faf0ab7417fbc6eb99fb0fd407e01e9e9dfe bafaecd11df15ad5b1e598adc7736afcd38ee13d 0d1622d7f526311d87d7da2ee7dd14b73e45d3fc Thanks, Anton. On Mar 23, 2010, at 8:54 PM, Linus Torvalds wrote: >=20 >=20 > On Tue, 23 Mar 2010, Anton Starikov wrote: >=20 >>=20 >> On Mar 23, 2010, at 6:45 PM, Linus Torvalds wrote: >>=20 >>>=20 >>>=20 >>> On Tue, 23 Mar 2010, Ingo Molnar wrote: >>>>=20 >>>> It shows a very brutal amount of page fault invoked mmap_sem = spinning=20 >>>> overhead. >>>=20 >>> Isn't this already fixed? It's the same old "x86-64 rwsemaphores are = using=20 >>> the shit-for-brains generic version" thing, and it's fixed by >>>=20 >>> 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 >>>=20 >>> NOTE! None of those are in 2.6.33 - they were merged afterwards. But = they=20 >>> are in 2.6.34-rc1 (and obviously current -git). So Anton would have = to=20 >>> compile his own kernel to test his load. >>=20 >>=20 >> Applied mentioned patches. Things didn't improve too much. >=20 > Yeah, I missed at least one commit, namely >=20 > bafaecd x86-64: support native xadd rwsem implementation >=20 > which is the one that actually makes x86-64 able to use the xadd = version. >=20 > 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