From owner-freebsd-stable Tue Jul 4 4: 1:39 2000 Delivered-To: freebsd-stable@freebsd.org Received: from mass.osd.bsdi.com (adsl-63-202-177-51.dsl.snfc21.pacbell.net [63.202.177.51]) by hub.freebsd.org (Postfix) with ESMTP id 6774C37B761 for ; Tue, 4 Jul 2000 04:01:36 -0700 (PDT) (envelope-from msmith@mass.osd.bsdi.com) Received: from mass.osd.bsdi.com (localhost [127.0.0.1]) by mass.osd.bsdi.com (8.9.3/8.9.3) with ESMTP id EAA02369; Tue, 4 Jul 2000 04:08:47 -0700 (PDT) (envelope-from msmith@mass.osd.bsdi.com) Message-Id: <200007041108.EAA02369@mass.osd.bsdi.com> X-Mailer: exmh version 2.1.1 10/15/1999 To: "Kenneth D. Merry" Cc: David Gilbert , Kent Stewart , freebsd-stable@FreeBSD.ORG Subject: Re: Dump takes ages on SCSI. (several times faster on IDE) In-reply-to: Your message of "Sun, 02 Jul 2000 23:55:24 MDT." <20000702235524.A19820@panzer.kdm.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Tue, 04 Jul 2000 04:08:47 -0700 From: Mike Smith Sender: owner-freebsd-stable@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > When the da(4) driver does a dump, it uses the CAM transport layer's polled > completion/action facility, xpt_polled_action(). > > It looks like there is a substantial delay (1ms) in that routine between > poll intervals. That would still allow 4MB/sec (1 page per I/O) - I think there's more to it than just that. -- ... every activity meets with opposition, everyone who acts has his rivals and unfortunately opponents also. But not because people want to be opponents, rather because the taks and relationships force people to take different points of view. [Dr. Fritz Todt] To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message