From owner-freebsd-stable@FreeBSD.ORG Mon Aug 16 14:46:39 2010 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 8EB031065695; Mon, 16 Aug 2010 14:46:39 +0000 (UTC) (envelope-from oberman@es.net) Received: from mailgw.es.net (mail1.es.net [IPv6:2001:400:201:1::2]) by mx1.freebsd.org (Postfix) with ESMTP id 74E428FC1B; Mon, 16 Aug 2010 14:46:39 +0000 (UTC) Received: from ptavv.es.net (ptavv.es.net [IPv6:2001:400:910::29]) by mailgw.es.net (8.14.3/8.14.3) with ESMTP id o7GEkcDJ004241 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NOT); Mon, 16 Aug 2010 07:46:38 -0700 Received: from ptavv.es.net (localhost [127.0.0.1]) by ptavv.es.net (Tachyon Server) with ESMTP id 4ACF81CC3A; Mon, 16 Aug 2010 07:46:38 -0700 (PDT) To: Ivan Voras In-reply-to: Your message of "Mon, 16 Aug 2010 15:03:23 +0200." Date: Mon, 16 Aug 2010 07:46:38 -0700 From: "Kevin Oberman" Message-Id: <20100816144638.4ACF81CC3A@ptavv.es.net> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:5.0.10011, 1.0.148, 0.0.0000 definitions=2010-08-16_02:2010-08-16, 2010-08-16, 1970-01-01 signatures=0 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 spamscore=0 ipscore=0 phishscore=0 bulkscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx engine=5.0.0-1005130000 definitions=main-1008160092 Cc: freebsd-stable@freebsd.org Subject: Re: Inconsistent IO performance X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 16 Aug 2010 14:46:39 -0000 > From: Ivan Voras > Date: Mon, 16 Aug 2010 15:03:23 +0200 > Sender: owner-freebsd-stable@freebsd.org > > On 13.8.2010 18:01, Kevin Oberman wrote: > > For some time I have seen very odd issues with IO performance on > > 8-Stable. Going back to November of last year when 8.0 was released, I > > see variations of up to 22% in identical operations. This is not a > > degradation as the performance moves up and down. > > In 8.0-8.1 span of time there was some work on the ata driver to make it > use MAXPHYS (128 KiB) transfer sizes instead of 64 KiB. Modifying this > will involve changing and recompiling the kernel but if you want to try > something and the hardware is SATA you might try the new AHCI driver > ("ada"). > > http://ivoras.net/blog/tree/2009-11-17.trying-ahci-in-8.0.html Thanks. I appreciate the suggestion. I am running a 8-Stable kernel from August 9, so I think I should be OK on this. IS there a requirement to set some parameter in the kernel config to take advantage of this? While the ThinkPad has a SATA ICH6-M chip-set, it does not provide or any SATA connections. Both SATA ports a run to a SATA/PATA converter chip and the only 2 physical connections available are PATA. I am assuming that this is because 2.5 in. SATA drives were pretty much unavailable when this system was shipped. This was the last of the T43 series and was dropped from the product line by Lenovo about a month after I got it, to be replaced by T60 systems running Core2 chips and using SATA drives. Just lousy timing almost 4 years ago. Thanks again! -- R. Kevin Oberman, Network Engineer Energy Sciences Network (ESnet) Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab) E-mail: oberman@es.net Phone: +1 510 486-8634 Key fingerprint:059B 2DDF 031C 9BA3 14A4 EADA 927D EBB3 987B 3751