From owner-freebsd-smp Wed Feb 21 10:56:16 2001 Delivered-To: freebsd-smp@freebsd.org Received: from mobile.hub.org (mobile.acadiau.ca [131.162.137.70]) by hub.freebsd.org (Postfix) with ESMTP id 75C5337B65D for ; Wed, 21 Feb 2001 10:56:07 -0800 (PST) (envelope-from scrappy@hub.org) Received: from localhost (scrappy@localhost) by mobile.hub.org (8.11.1/8.11.1) with ESMTP id f1LIu3V17809 for ; Wed, 21 Feb 2001 14:56:03 -0400 (AST) (envelope-from scrappy@hub.org) X-Authentication-Warning: mobile.hub.org: scrappy owned process doing -bs Date: Wed, 21 Feb 2001 14:56:03 -0400 (AST) From: The Hermit Hacker To: Subject: IOPs ... what exactly are they? Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-smp@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.org Searching google isn't coming up with anything that explains it ... can someone point me to some docs, or provide an explanation? For instance, Tom stated that the 170 does 4000IOPs, vs the 352 at 7000IOPs ... yet, the 352 will do twice the sustained transferof the 170 (200MB/s vs 100MB/s) ... so, IOPs don't == transfer speed ... And, I imagine (can't get to the Mylex web site right now for some reason), the 2000 has an even higher rating then both of those ... So, when evaluating what one needs, how do you determine? are there thresholds one can work with? 4000IOPs will comfortably handle n xgig drives, but if you go above n, then you really need to jump to the 7k IOP level else performance drops substantially? We're looking at this for a database server, so will most likely be going to the 64MB cache level automatically ... but beyond that, I'm virtually uneducated :( Marc G. Fournier ICQ#7615664 IRC Nick: Scrappy Systems Administrator @ hub.org primary: scrappy@hub.org secondary: scrappy@{freebsd|postgresql}.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-smp" in the body of the message