Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758516Ab3CYOoa (ORCPT ); Mon, 25 Mar 2013 10:44:30 -0400 Received: from a192-166.smtp-out.amazonses.com ([199.255.192.166]:9855 "EHLO a192-166.smtp-out.amazonses.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758445Ab3CYOoZ (ORCPT ); Mon, 25 Mar 2013 10:44:25 -0400 X-Greylist: delayed 566 seconds by postgrey-1.27 at vger.kernel.org; Mon, 25 Mar 2013 10:44:25 EDT Date: Mon, 25 Mar 2013 14:34:58 +0000 From: Christoph Lameter X-X-Sender: cl@gentwo.org To: Steven Rostedt cc: LKML , RT , Thomas Gleixner , Clark Williams Subject: Re: [RT LATENCY] 249 microsecond latency caused by slub's unfreeze_partials() code. In-Reply-To: <1364010673.6345.156.camel@gandalf.local.home> Message-ID: <0000013da1f93be3-c3d42ae8-ff34-4c63-8094-77a83291ea19-000000@email.amazonses.com> References: <1363906545.6345.81.camel@gandalf.local.home> <0000013d92c37ff3-5fb85400-bec1-4eda-8ba1-332566884c59-000000@email.amazonses.com> <1364010673.6345.156.camel@gandalf.local.home> User-Agent: Alpine 2.02 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-SES-Outgoing: 199.255.192.166 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 655 Lines: 23 On Fri, 22 Mar 2013, Steven Rostedt wrote: > I uploaded it here: > > http://rostedt.homelinux.com/private/slab_partials > > See anything I should be worried about? Looks fine. Maybe its the spinlocks being contended that cause the long holdoff? How does RT deal with the spinlocks? Dont know too much about it. You can eliminate the whole thing by setting /sys/kernel/slab/