From owner-freebsd-hackers Thu May 13 16:32:18 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from allegro.lemis.com (allegro.lemis.com [192.109.197.134]) by hub.freebsd.org (Postfix) with ESMTP id BBBC914EA2 for ; Thu, 13 May 1999 16:32:08 -0700 (PDT) (envelope-from grog@freebie.lemis.com) Received: from freebie.lemis.com (freebie.lemis.com [192.109.197.137]) by allegro.lemis.com (8.9.1/8.9.0) with ESMTP id JAA08488; Fri, 14 May 1999 09:02:03 +0930 (CST) Received: (from grog@localhost) by freebie.lemis.com (8.9.3/8.9.0) id JAA66550; Fri, 14 May 1999 09:02:00 +0930 (CST) Date: Fri, 14 May 1999 09:02:00 +0930 From: Greg Lehey To: Andrew Doran Cc: Chuck Youse , freebsd-hackers@FreeBSD.ORG Subject: DPT performance (was: fsck and large file system) Message-ID: <19990514090159.A89091@freebie.lemis.com> References: <373A952C.4AFAA37C@fionn.sports.gov.uk> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Mailer: Mutt 0.95.4i In-Reply-To: <373A952C.4AFAA37C@fionn.sports.gov.uk>; from Andrew Doran on Thu, May 13, 1999 at 10:02:36AM +0100 WWW-Home-Page: http://www.lemis.com/~grog X-PGP-Fingerprint: 6B 7B C3 8C 61 CD 54 AF 13 24 52 F8 6D A4 95 EF Organization: LEMIS, PO Box 460, Echunga SA 5153, Australia Phone: +61-8-8388-8286 Fax: +61-8-8388-8725 Mobile: +61-41-739-7062 Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Thursday, 13 May 1999 at 10:02:36 +0100, Andrew Doran wrote: > Chuck Youse wrote: > >> Whoa ... can anyone substantiate that this poor performance is typical >> or atypical of DPT SCSI RAID controllers? > > This is atypical, What's typical? Have you (or anybody else) done any measurements? I'd be very interested to see other results. > however DPT HBAs are *very* touchy about termination and > cabling. For instance, with two identical (old) Seagate Hawks on a > SmartCache III, I get 2MB/s reads from one and 500kB/s from the > other. Have you analysed the reasons for this discrepancy? If you can't get rid of the problem, it's not exactly an advertisement for DPT. Greg -- See complete headers for address, home page and phone numbers finger grog@lemis.com for PGP public key To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message