Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752385AbbFZJMB (ORCPT ); Fri, 26 Jun 2015 05:12:01 -0400 Received: from mail-wi0-f179.google.com ([209.85.212.179]:37163 "EHLO mail-wi0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751790AbbFZJLy (ORCPT ); Fri, 26 Jun 2015 05:11:54 -0400 Message-ID: <1435309910.4110.74.camel@edumazet-glaptop2.roam.corp.google.com> Subject: Re: [GIT PULL] Locking changes for v4.2 From: Eric Dumazet To: Ingo Molnar Cc: Linus Torvalds , linux-kernel@vger.kernel.org, Peter Zijlstra , Thomas Gleixner , "Paul E. McKenney" , Andrew Morton Date: Fri, 26 Jun 2015 11:11:50 +0200 In-Reply-To: <20150622073015.GA1986@gmail.com> References: <20150622073015.GA1986@gmail.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.10.4-0ubuntu2 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1669 Lines: 69 On Mon, 2015-06-22 at 09:30 +0200, Ingo Molnar wrote: > Linus, > > Please pull the latest locking-core-for-linus git tree from: > > git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git locking-core-for-linus > > # HEAD: 68722101ec3a0e179408a13708dd020e04f54aab locking/lockdep: Remove hard coded array size dependency > > The main changes are: > > - 'qspinlock' support, enabled on x86: queued spinlocks - these are now the > spinlock variant used by x86 as they outperform ticket spinlocks in every > category. (Waiman Long) Very interesting. While rebasing http://www.kernelhub.org/?msg=737214&p=2 I found that indeed qspinlock improved the scalability issue by a big factor. linux-4.1 lpaa23:~# pipebench -n 16 threads:16 sleep:30 pinned:1 total operations: 6977349, ops/sec 232578 6977349 lpaa23:~# pipebench -n 16 threads:16 sleep:30 pinned:1 total operations: 7326280, ops/sec 244209 7326280 Current Linus tree : lpaa23:~# pipebench -n 16 threads:16 sleep:30 pinned:1 total operations: 15640802, ops/sec 521360 15640802 lpaa23:~# pipebench -n 16 threads:16 sleep:30 pinned:1 total operations: 15045022, ops/sec 501500 15045022 Adding fd_install() patch then : lpaa23:~# pipebench -n 16 threads:16 sleep:30 pinned:1 total operations: 21471043, ops/sec 715701 21471043 lpaa23:~# pipebench -n 16 threads:16 sleep:30 pinned:1 total operations: 21068501, ops/sec 702283 21068501 -- 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/