Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752835Ab1EQHUj (ORCPT ); Tue, 17 May 2011 03:20:39 -0400 Received: from mx2.fusionio.com ([66.114.96.31]:39717 "EHLO mx2.fusionio.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752551Ab1EQHUf (ORCPT ); Tue, 17 May 2011 03:20:35 -0400 X-ASG-Debug-ID: 1305616833-01de28096b40fd0001-xx1T2L X-Barracuda-Envelope-From: JAxboe@fusionio.com Message-ID: <4DD221BE.3040406@fusionio.com> Date: Tue, 17 May 2011 09:20:30 +0200 From: Jens Axboe MIME-Version: 1.0 To: "Alex,Shi" CC: "Li, Shaohua" , "James.Bottomley@hansenpartnership.com" , "linux-kernel@vger.kernel.org" Subject: Re: Perfromance drop on SCSI hard disk References: <1305009600.21534.587.camel@debian> <4DCC4340.6000407@fusionio.com> <1305247704.2373.32.camel@sli10-conroe> <1305255717.2373.38.camel@sli10-conroe> <1305533054.2375.45.camel@sli10-conroe> <1305535071.21534.2122.camel@debian> <1305612565.21534.2177.camel@debian> X-ASG-Orig-Subj: Re: Perfromance drop on SCSI hard disk In-Reply-To: <1305612565.21534.2177.camel@debian> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Barracuda-Connect: mail1.int.fusionio.com[10.101.1.21] X-Barracuda-Start-Time: 1305616833 X-Barracuda-URL: http://10.101.1.181:8000/cgi-mod/mark.cgi X-Barracuda-Spam-Score: 0.00 X-Barracuda-Spam-Status: No, SCORE=0.00 using global scores of TAG_LEVEL=1000.0 QUARANTINE_LEVEL=1000.0 KILL_LEVEL=9.0 tests= X-Barracuda-Spam-Report: Code version 3.2, rules version 3.2.2.63976 Rule breakdown below pts rule name description ---- ---------------------- -------------------------------------------------- Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1163 Lines: 27 On 2011-05-17 08:09, Alex,Shi wrote: > On Mon, 2011-05-16 at 16:37 +0800, Alex,Shi wrote: >>>> what I mean is current sdev (other devices too) can still be added into >>>> starved list, so only does async execute for current q isn't enough, >>>> we'd better put whole __scsi_run_queue into workqueue. something like >>>> below on top of yours, untested. Not sure if there are other recursive >>>> cases. >>> verified the regression can be fully fixed by your patch (with my >>> suggested fix to avoid race). Can we put a formal patch upstream? >> >> Yes, we tested Jens patch alone and plus Shaohua's patch too. Both of >> them recovered SAS disk performance too. Now I am testing them on SSD >> disk with kbuild and fio cases, In theory, they will both work. >> > > As expected, both patches has no effect on SSD disks in JBD. I will queue up the combined patch, it looks fine from here as well. -- Jens Axboe -- 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/