Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755583AbcC3REY (ORCPT ); Wed, 30 Mar 2016 13:04:24 -0400 Received: from mail-yw0-f195.google.com ([209.85.161.195]:33634 "EHLO mail-yw0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755403AbcC3REW (ORCPT ); Wed, 30 Mar 2016 13:04:22 -0400 Date: Wed, 30 Mar 2016 13:04:19 -0400 From: Tejun Heo To: Michael Rapoport Cc: Bandan Das , linux-kernel@vger.kernel.org, kvm@vger.kernel.org, mst@redhat.com, jiangshanlai@gmail.com Subject: Re: [RFC PATCH 0/4] cgroup aware workqueues Message-ID: <20160330170419.GG7822@mtj.duckdns.org> References: <1458339291-4093-1-git-send-email-bsd@redhat.com> <201603210758.u2L7wiY9003907@d06av07.portsmouth.uk.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <201603210758.u2L7wiY9003907@d06av07.portsmouth.uk.ibm.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 Content-Length: 676 Lines: 20 Hello, On Mon, Mar 21, 2016 at 09:58:39AM +0200, Michael Rapoport wrote: > I did some performance evaluation of different threading models in vhost, > and in most tests replacing vhost kthread's with workqueues degrades the > performance. Moreover, having thread management inside the vhost provides There really shouldn't be any difference when using unbound workqueues. workqueue becomes a convenience thing which manages worker pools and there shouldn't be any difference between workqueue workers and kthreads in terms of behavior. > opportunity for optimization, at least for some workloads... What sort of optimizations are we talking about? Thanks. -- tejun