From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Jack Wang" Subject: RE: pm8001 performance degradation? Date: Tue, 12 Jul 2011 12:18:45 +0800 Message-ID: <9E591616165B4B14A80DE392145C99FC@usish.com.cn> References: <316E3E573B654596BA694678AE395999@usish.com.cn> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Return-path: Received: from sr-smtp.usish.com ([210.5.144.203]:55948 "EHLO sr-smtp.usish.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751042Ab1GLESy convert rfc822-to-8bit (ORCPT ); Tue, 12 Jul 2011 00:18:54 -0400 In-Reply-To: Sender: linux-scsi-owner@vger.kernel.org List-Id: linux-scsi@vger.kernel.org To: 'ersatz splatt' Cc: lindar_liu@usish.com, linux-scsi@vger.kernel.org Could you share your fio test scripts? disk detail and HBA firmware ver= sion are also wanted if available. Jack >=20 > I have one HBA connected directly to 4 SAS drives ... using a single = 1 > to four cable. >=20 >=20 > On Mon, Jul 11, 2011 at 6:27 PM, Jack Wang wrot= e: > >> Hello Jack Wang and Lindar Liu, > >> > >> > >> I am running the pm8001 driver (on applicable hardware including a > >> several core SMP server). > >> > >> When I run on an older kernel -- e.g. 2.6.34.7 -- I get about 73Ki= ops > >> via an fio test. > >> > >> When I run a current kernel -- e.g. 2.6.39.2 -- on the same system= and > >> same storage I get about 15Kiops running the same fio test. > >> > >> Perhaps something has changes in the kernel that is not being acco= unted > > for? > >> Are you two still maintaining this driver? > >> > >> > >> Regards, > >> David > > [Jack Wang] =A0Could you give your detailed topology, I will later = try to > > investigate the performance issue, but as I remember an Intel devel= oper > > reports in mailist some changes in block layer lead to JBOD perform= ance > > degradation. > > > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-scsi"= in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" i= n the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html