Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932874AbaLDRos (ORCPT ); Thu, 4 Dec 2014 12:44:48 -0500 Received: from userp1040.oracle.com ([156.151.31.81]:28905 "EHLO userp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932632AbaLDRoq (ORCPT ); Thu, 4 Dec 2014 12:44:46 -0500 Message-ID: <54809D7F.4020901@oracle.com> Date: Thu, 04 Dec 2014 09:44:31 -0800 From: Shirley Ma User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.7.0 MIME-Version: 1.0 To: Jeff Layton CC: Trond Myklebust , Tejun Heo , NeilBrown , Linux NFS Mailing List , Linux Kernel mailing list , Al Viro Subject: Re: [RFC PATCH 00/14] nfsd/sunrpc: add support for a workqueue-based nfsd References: <1417544663-13299-1-git-send-email-jlayton@primarydata.com> <20141203121118.21a32fe1@notabene.brown> <20141202202946.1e0f399b@tlielax.poochiereds.net> <20141203155649.GB5013@htj.dyndns.org> <20141203110405.5ecc85df@tlielax.poochiereds.net> <20141203140202.7865bedb@tlielax.poochiereds.net> <20141203142034.5c14529d@tlielax.poochiereds.net> <20141203152147.2ca6c6fd@tlielax.poochiereds.net> <20141204064711.72d48317@tlielax.poochiereds.net> <5480971D.9010102@oracle.com> <20141204122845.3f9e3a04@tlielax.poochiereds.net> In-Reply-To: <20141204122845.3f9e3a04@tlielax.poochiereds.net> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Source-IP: acsinet22.oracle.com [141.146.126.238] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/04/2014 09:28 AM, Jeff Layton wrote: > On Thu, 04 Dec 2014 09:17:17 -0800 > Shirley Ma wrote: > >> > I am looking at how to reduce total RPC execution time in NFS/RDMA. mountstats output shows that RPC backlog wait is too long, but increasing the credit limit doesn't seem help. Would this patchset help reducing total RPC execution time? >> > >> > Shirley >> > > I'm not sure. It depends on why you're seeing a backlog. What's the major factors contributing RPC backlog wait time? I guess I need to probe the backlog wait path to display fine-grained latency cost. > So far, my testing still shows this to be slightly (~2%) slower than the > same setup running a threaded nfsd, but that could be different with a > NUMA server or faster disks. > > Probably there is some more tuning to do here before this is quite > ready for prime-time. It may be worth testing in your environment > though if you have the time and ability to do so. > >> > On 12/04/2014 03:47 AM, Jeff Layton wrote: >>> > > I was using ftrace with the sunrpc:* and workqueue:* tracepoints, and >>> > > had a simple perl script to postprocess the trace info to figure out >>> > > average/min/max latency. -- 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/