From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755837Ab3GYLGH (ORCPT ); Thu, 25 Jul 2013 07:06:07 -0400 Received: from mail-vb0-f48.google.com ([209.85.212.48]:52785 "EHLO mail-vb0-f48.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755574Ab3GYLGE (ORCPT ); Thu, 25 Jul 2013 07:06:04 -0400 Message-ID: <1374750359.23313.17.camel@edumazet-glaptop> Subject: Re: Hack bench regression with CONFIG_SLUB_CPU_PARTIAL disabled (info only) From: Eric Dumazet To: Raghavendra K T Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "David S. Miller" , "Eric W. Biederman" , Eric Dumazet , Al Viro , Gao feng Date: Thu, 25 Jul 2013 04:05:59 -0700 In-Reply-To: <51F0DB11.2080508@linux.vnet.ibm.com> References: <51F0DB11.2080508@linux.vnet.ibm.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2013-07-25 at 13:30 +0530, Raghavendra K T wrote: > Hi, > > While testing hackbench with 3.11-rc1 I observed hackbench testcase > took too long to complete (32 vcpu kvm guest on 32 core HT off machine). > > hackbench 1x degraded by 3 time (40sec vs 112sec) > hackbench 2x degraded by around 20time (90sec vs 1800 sec) > > When I bisected, I found that I had CONFIG_SLUB_CPU_PARTIAL > accidentally disabled. > I understand that CONFIG_SLUB_CPU_PARTIAL=y by default and the config > option is to provide determinism for RT kernels and thus it is not a > problem. > But thought of sharing this here so that if somebody runs into same > issue accidently, it would save their time. Incidentally, what difference do you currently get with SLUB and SLAB ?