From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755015AbcEEODe (ORCPT ); Thu, 5 May 2016 10:03:34 -0400 Received: from mx2.suse.de ([195.135.220.15]:53259 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752471AbcEEODd (ORCPT ); Thu, 5 May 2016 10:03:33 -0400 Date: Thu, 5 May 2016 16:03:29 +0200 From: Jan Kara To: Waiman Long Cc: "Theodore Ts'o" , Andreas Dilger , Alexander Viro , Matthew Wilcox , linux-ext4@vger.kernel.org, linux-kernel@vger.kernel.org, Dave Chinner , Christoph Hellwig , Scott J Norton , Douglas Hatch , Toshimitsu Kani Subject: Re: [PATCH v5 2/2] ext4: Make cache hits/misses per-cpu counts Message-ID: <20160505140329.GI1970@quack2.suse.cz> References: <1461947276-25988-1-git-send-email-Waiman.Long@hpe.com> <1461947276-25988-3-git-send-email-Waiman.Long@hpe.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1461947276-25988-3-git-send-email-Waiman.Long@hpe.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri 29-04-16 12:27:56, Waiman Long wrote: > This patch changes the es_stats_cache_hits and es_stats_cache_misses > statistics counts to percpu counters to reduce cacheline contention > issues whem multiple threads are trying to update those counts > simultaneously. > > With a 38-threads fio I/O test with 2 shared files (on DAX-mount > NVDIMM) running on a 4-socket Haswell-EX server with 4.6-rc1 kernel, > the aggregated bandwidths before and after the patch were: > > Test W/O patch With patch % change > ---- --------- ---------- -------- > Read-only 16499MB/s 17215MB/s +4.3% > Read-write 4361MB/s 4794MB/s +9.9% > > Signed-off-by: Waiman Long The patch looks good. You can add: Reviewed-by: Jan Kara Honza -- Jan Kara SUSE Labs, CR