From owner-freebsd-bugs Fri Apr 7 6:18:27 2000 Delivered-To: freebsd-bugs@freebsd.org Received: from arjun.niksun.com (gwnew.niksun.com [206.20.52.130]) by hub.freebsd.org (Postfix) with ESMTP id 250C237BB71; Fri, 7 Apr 2000 06:18:20 -0700 (PDT) (envelope-from ath@niksun.com) Received: from celis.niksun.com (celis.niksun.com [10.1.0.48]) by arjun.niksun.com (8.9.3/8.9.3) with ESMTP id JAA15229; Fri, 7 Apr 2000 09:18:16 -0400 (EDT) (envelope-from ath@celis.niksun.com) Received: from celis (localhost [127.0.0.1]) by celis.niksun.com (8.9.3/8.9.2) with ESMTP id JAA15202; Fri, 7 Apr 2000 09:18:02 -0400 (EDT) (envelope-from ath@celis.niksun.com) Message-Id: <200004071318.JAA15202@celis.niksun.com> From: Andrew Heybey To: "Justin T. Gibbs" Cc: mjacob@feral.com, freebsd-bugs@FreeBSD.ORG, freebsd-scsi@FreeBSD.ORG Subject: Re: kern/17153 (was: newfs on IBM disks slower than Seagate disks?) In-reply-to: Your message of Wed, 05 Apr 2000 20:07:26 -0600. <200004060207.UAA24407@caspian.plutotech.com> Mime-Version: 1.0 (generated by tm-edit 7.108) Content-Type: text/plain; charset=US-ASCII Date: Fri, 07 Apr 2000 09:18:02 -0400 Sender: owner-freebsd-bugs@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org It would seem that the WCE bit is the answer. The IBM has it set to zero while the Seagates have it set to 1. Unlike Matt Jacob, I get substantially the same performance for normal IO: IBM: install8 1# dd if=/dev/rda0s1c of=/dev/null bs=1024k count=200 200+0 records in 200+0 records out 209715200 bytes transferred in 7.561781 secs (27733572 bytes/sec) Seagate: su-2.03# dd if=/dev/rda0s1c of=/dev/null bs=1024k count=200 200+0 records in 200+0 records out 209715200 bytes transferred in 7.520681 secs (27885135 bytes/sec) I don't have any partitions lying around that I can newfs to test the WCE hypothesis, but it seems the most logical answer. andrew To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-bugs" in the body of the message