From owner-freebsd-scsi@FreeBSD.ORG Fri Jun 23 16:18:46 2006 Return-Path: X-Original-To: freebsd-scsi@freebsd.org Delivered-To: freebsd-scsi@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 9F9F416A47E for ; Fri, 23 Jun 2006 16:18:46 +0000 (UTC) (envelope-from gibbs@scsiguy.com) Received: from ns1.scsiguy.com (ns1.scsiguy.com [70.89.174.89]) by mx1.FreeBSD.org (Postfix) with ESMTP id 2AA0543D48 for ; Fri, 23 Jun 2006 16:18:44 +0000 (GMT) (envelope-from gibbs@scsiguy.com) Received: from [10.0.0.22] (63-138-13-146.customer.static.ip.paetec.net [63.138.13.146] (may be forged)) (authenticated bits=0) by ns1.scsiguy.com (8.13.6/8.13.6) with ESMTP id k5NGIfLI020401 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Fri, 23 Jun 2006 10:18:42 -0600 (MDT) (envelope-from gibbs@scsiguy.com) Date: Fri, 23 Jun 2006 10:18:33 -0600 From: "Justin T. Gibbs" To: Volodymyr Kostyrko Message-ID: <5272604BA34A45926DFA0D2F@[10.0.0.22]> In-Reply-To: <449C0E34.3080005@synergetica.dn.ua> References: <4499B748.6040805@synergetica.dn.ua> <90D11403BD2140875BFEB24D@[10.0.0.22]> <449C0E34.3080005@synergetica.dn.ua> X-Mailer: Mulberry/3.1.6 (Win32) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline Cc: freebsd-scsi@freebsd.org Subject: Re: ahd(4) poor performance X-BeenThere: freebsd-scsi@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: SCSI subsystem List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 23 Jun 2006 16:18:46 -0000 dd is synchronous. You'd need to aggregate the throughput of several dd operations to see the impact of overlapped commands. -- Justin --On Friday, June 23, 2006 6:52 PM +0300 Volodymyr Kostyrko wrote: > Justin T. Gibbs ?????: >> --On Thursday, June 22, 2006 12:16 AM +0300 Volodymyr Kostyrko >> wrote: >> >>> Hi all. >>> >>> I have: >>> >>> ahd0: port >>> 0xdc00-0xdcff,0xd800-0xd8ff mem 0xdfbfe000-0xdfbfffff irq 66 at device >>> 7.0 on pci3 >>> ahd0: [GIANT-LOCKED] >>> aic7902: Ultra320 Wide Channel A, SCSI Id=7, PCI-X 101-133Mhz, 512 SCBs >>> ahd1: port >>> 0xd400-0xd4ff,0xd000-0xd0ff mem 0xdfbfc000-0xdfbfdfff irq 67 at device >>> 7.1 on pci3 >>> ahd1: [GIANT-LOCKED] >>> aic7902: Ultra320 Wide Channel B, SCSI Id=7, PCI-X 101-133Mhz, 512 SCBs >>> >>> Booting machine also results in: >>> >>> ahd0: Invalid Sequencer interrupt occurred. >> >> This error is benign. >> >> There have been issues reported with some recent Seagate drives and >> large queue depths. You may get better performance if you use camcontrol >> to lower the queue depth to 63 or 32. I believe that 32 is the default >> used by Linux. >> >> -- >> Justin > > Interesting. > > By default I have the following: > > srv4# camcontrol tags 0:0 -v > (pass1:ahd0:0:1:0): dev_openings 1 > (pass1:ahd0:0:1:0): dev_active 0 > (pass1:ahd0:0:1:0): devq_openings 1 > (pass1:ahd0:0:1:0): devq_queued 0 > (pass1:ahd0:0:1:0): held 0 > (pass1:ahd0:0:1:0): mintags 2 > (pass1:ahd0:0:1:0): maxtags 255 > > Raising this to higher values provides better perfomance: > > @1: > > > dd if=/dev/zero of=somefile count=20480 > 20480+0 records in > 20480+0 records out > 10485760 bytes transferred in 1.114188 secs (9411123 bytes/sec) > > @2: > > > dd if=/dev/zero of=somefile count=20480 > 20480+0 records in > 20480+0 records out > 10485760 bytes transferred in 0.402884 secs (26026747 bytes/sec) > > Raising it further doesn't help anyway. And it still behaves not so > fast as Linux. > > -- > [WBR], Arcade. >