From owner-freebsd-questions@FreeBSD.ORG Fri Jun 13 14:16:17 2008 Return-Path: Delivered-To: questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id B2B0F1065683; Fri, 13 Jun 2008 14:16:17 +0000 (UTC) (envelope-from wojtek@wojtek.tensor.gdynia.pl) Received: from wojtek.tensor.gdynia.pl (wojtek.tensor.gdynia.pl [IPv6:2001:4070:101:2::1]) by mx1.freebsd.org (Postfix) with ESMTP id 9E22A8FC25; Fri, 13 Jun 2008 14:16:16 +0000 (UTC) (envelope-from wojtek@wojtek.tensor.gdynia.pl) Received: from wojtek.tensor.gdynia.pl (localhost [IPv6:::1]) by wojtek.tensor.gdynia.pl (8.14.2/8.14.2) with ESMTP id m5DEF6ru001562; Fri, 13 Jun 2008 16:15:06 +0200 (CEST) (envelope-from wojtek@wojtek.tensor.gdynia.pl) Received: from localhost (wojtek@localhost) by wojtek.tensor.gdynia.pl (8.14.2/8.14.2/Submit) with ESMTP id m5DEF6Qj001559; Fri, 13 Jun 2008 16:15:06 +0200 (CEST) (envelope-from wojtek@wojtek.tensor.gdynia.pl) Date: Fri, 13 Jun 2008 16:15:06 +0200 (CEST) From: Wojciech Puchar To: David Kelly In-Reply-To: <20080613140130.GA8616@Grumpy.DynDNS.org> Message-ID: <20080613161329.U1540@wojtek.tensor.gdynia.pl> References: <200806121521.16237.kirk@strauser.com> <20080613090714.K4713@wojtek.tensor.gdynia.pl> <20080613140130.GA8616@Grumpy.DynDNS.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Cc: FreeBSD Questions , freebsd-questions@freebsd.org Subject: Re: Stripe sizes with gstripe X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 13 Jun 2008 14:16:17 -0000 >> then single read is rarely split on 2 disks, while multiple reads have >> good chances to touch different drives > > Come to think of it I didn't try setting the stripe size larger than the > ATA max transaction size of 128k. yes it is. max transaction doesn't begin on boundary. may (usually will) start somewhere inbetween. making stripe size >>max transaction makes it inprobable. BTW you mean ATA max transaction or FreeBSD default MAXBSIZE, which i change to 1MB