From owner-freebsd-hackers@FreeBSD.ORG Thu Oct 11 22:02:54 2012 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [69.147.83.52]) by hub.freebsd.org (Postfix) with ESMTP id 2DAD2D35; Thu, 11 Oct 2012 22:02:54 +0000 (UTC) (envelope-from rmacklem@uoguelph.ca) Received: from esa-annu.mail.uoguelph.ca (esa-annu.mail.uoguelph.ca [131.104.91.36]) by mx1.freebsd.org (Postfix) with ESMTP id BC0AF8FC17; Thu, 11 Oct 2012 22:02:53 +0000 (UTC) X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: Ap0EAJ+LclCDaFvO/2dsb2JhbABFhhG6GYJKVhsODAINGQJfiBimVJF1gSGPLIESA5VrkC6DCYF7 X-IronPort-AV: E=Sophos;i="4.80,574,1344225600"; d="scan'208";a="186031155" Received: from erie.cs.uoguelph.ca (HELO zcs3.mail.uoguelph.ca) ([131.104.91.206]) by esa-annu-pri.mail.uoguelph.ca with ESMTP; 11 Oct 2012 18:02:52 -0400 Received: from zcs3.mail.uoguelph.ca (localhost.localdomain [127.0.0.1]) by zcs3.mail.uoguelph.ca (Postfix) with ESMTP id C0136B4096; Thu, 11 Oct 2012 18:02:52 -0400 (EDT) Date: Thu, 11 Oct 2012 18:02:52 -0400 (EDT) From: Rick Macklem To: Nikolay Denev Message-ID: <608951636.2115684.1349992972756.JavaMail.root@erie.cs.uoguelph.ca> Subject: Re: NFS server bottlenecks MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Originating-IP: [172.17.91.201] X-Mailer: Zimbra 6.0.10_GA_2692 (ZimbraWebClient - IE7 (Win)/6.0.10_GA_2692) Cc: FreeBSD Hackers , Garrett Wollman X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 11 Oct 2012 22:02:54 -0000 Oops, I didn't get the "readahead" option description quite right in the last post. The default read ahead is 1, which does result in "rsize * 2", since there is the read + 1 readahead. "rsize * 16" would actually be for the option "readahead=15" and for "readahead=16" the calculation would be "rsize * 17". However, the example was otherwise ok, I think? rick