From owner-freebsd-scsi Sat Feb 13 03:00:15 1999 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id DAA23294 for freebsd-scsi-outgoing; Sat, 13 Feb 1999 03:00:15 -0800 (PST) (envelope-from owner-freebsd-scsi@FreeBSD.ORG) Received: from picalon.gun.de (picalon.gun.de [194.77.0.18] (may be forged)) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id DAA23288 for ; Sat, 13 Feb 1999 03:00:11 -0800 (PST) (envelope-from andreas@klemm.gtn.com) Received: from klemm.gtn.com (pppak04.gtn.com [194.231.123.169]) by picalon.gun.de (8.8.6/8.8.6) with ESMTP id MAA16920; Sat, 13 Feb 1999 12:00:06 +0100 (MET) Received: (from andreas@localhost) by klemm.gtn.com (8.9.2/8.9.2) id LAA06376; Sat, 13 Feb 1999 11:46:41 +0100 (CET) (envelope-from andreas) Date: Sat, 13 Feb 1999 11:46:41 +0100 From: Andreas Klemm To: "Kenneth D. Merry" Cc: mjacob@feral.com, ANDREAS.KLEMM.AK@bayer-ag.de, scsi@FreeBSD.ORG Subject: Re: It%s not the write cache on 3.0-STABLE and not tagged comma Message-ID: <19990213114641.B6068@titan.klemm.gtn.com> References: <199902121602.JAA34641@panzer.plutotech.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.95.1i In-Reply-To: <199902121602.JAA34641@panzer.plutotech.com>; from Kenneth D. Merry on Fri, Feb 12, 1999 at 09:02:18AM -0700 X-Disclaimer: A free society is one where it is safe to be unpopular X-Operating-System: FreeBSD 3.0-STABLE SMP Sender: owner-freebsd-scsi@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org On Fri, Feb 12, 1999 at 09:02:18AM -0700, Kenneth D. Merry wrote: > > He is getting poor performance for sequential writes with a Seagate disk > under CAM. Write throughput to the disk is fairly erratic. (i.e., lots of > ups and downs) > > He has the problem under 2.2.7 with tagged queueing enabled, but not when > he disables tagged queueing. The problem occurs under 3.0 with or > without tagged queueing. > > I told him to disable write caching, since I have seen similar problems > when write caching is enabled, but that didn't seem to fix the problem. > > Any ideas? BTW, a friend of mine works for VIVA. They have lots of HP Kajak's and he told me _lots_ of problems with firmware, since HP seems to put his _own_ drivers in everything they can ;-) He ponited me to HP's support site to do a firmware upgrade, but I couldn't find something for Harddisks :-/ But if write performance is poor, but actually doesn't eat up that much CPU performance. Why is the FreeBSD machine so much "in-responsive". It means I merely can login on a second console, I have to wait 10-15 seconds for a login. And the execution of commands lags lags lags. Ok, perhaps it's a race condition of the disk .... that perhaps login, csh and other things can't be read from disk, because it's upgly hung or busy transferring things for bonnie ... BTW, when HP puts his own firmware to a disk, do they change the description of the disk ... ? Or in other words, I wrote to you the description of the disk (SEAGATE bla...), doesn somebody other have this disk and such problems ??? -- Andreas Klemm http://www.FreeBSD.ORG/~andreas What gives you 90% more speed, for example, in kernel compilation ? http://www.FreeBSD.ORG/~fsmp/SMP/akgraph-a/graph1.html "NT = Not Today" (Maggie Biggs) ``powered by FreeBSD SMP'' To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-scsi" in the body of the message