From owner-freebsd-questions Sun Aug 12 1:37: 7 2001 Delivered-To: freebsd-questions@freebsd.org Received: from elvis.mu.org (elvis.mu.org [216.33.66.196]) by hub.freebsd.org (Postfix) with ESMTP id E72F337B406; Sun, 12 Aug 2001 01:37:05 -0700 (PDT) (envelope-from bright@elvis.mu.org) Received: by elvis.mu.org (Postfix, from userid 1192) id D201A81D05; Sun, 12 Aug 2001 03:37:05 -0500 (CDT) Date: Sun, 12 Aug 2001 03:37:05 -0500 From: Alfred Perlstein To: Greg Lehey Cc: Kevin Hui , freebsd-questions@freebsd.org Subject: Re: Experiencing very slow raw write speeds on /dev/ad1 Message-ID: <20010812033705.V85642@elvis.mu.org> References: <20010810025156.N85642@elvis.mu.org> <20010812180014.D48115@wantadilla.lemis.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <20010812180014.D48115@wantadilla.lemis.com>; from grog@FreeBSD.org on Sun, Aug 12, 2001 at 06:00:14PM +0930 Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG * Greg Lehey [010812 03:29] wrote: > > Linux and rawio are not really compatible. In Linux you have no > choice, you must go via buffer cache; this can give you results which > look much better. Also, sequential I/O is not very informative, > especially if you only have one process. It would be much more > interesting to look at random I/O and not change the default rawio > parameters (in particular, let 8 concurrent processes run). I was going to say that (linux cheats because it doesn't really have raw io), but I wasn't sure I was up to date enough. Thanks for taking the time to explain it. -- -Alfred Perlstein [alfred@freebsd.org] Ok, who wrote this damn function called '??'? And why do my programs keep crashing in it? To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message