From owner-freebsd-questions@FreeBSD.ORG Fri Jun 4 20:31:59 2010 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id AE326106567A for ; Fri, 4 Jun 2010 20:31:59 +0000 (UTC) (envelope-from amvandemore@gmail.com) Received: from mail-gy0-f182.google.com (mail-gy0-f182.google.com [209.85.160.182]) by mx1.freebsd.org (Postfix) with ESMTP id 5DFC48FC16 for ; Fri, 4 Jun 2010 20:31:59 +0000 (UTC) Received: by gyh20 with SMTP id 20so1626783gyh.13 for ; Fri, 04 Jun 2010 13:31:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:in-reply-to :references:date:message-id:subject:from:to:cc:content-type; bh=ke5OmX3szE4dP831mSJIUPgONSSURsB1Rqoq2+5K5SE=; b=s8SmMmkXbuJc3Ptm3rAjOug8NUIUWTRht67Gl07u/0P5Op93YI6JDPpEOrFzmGWVyw BpRXVKfXtoqmMvepoTv0dVhBGU4pDT3PI6B2xdK2bRRr8mNtJrtsmLaaYpV6fU6BTIeq Mh5gNhCrgyrfqTdxy0IHndRgUpxTDI0FNNZYI= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; b=hjhY6DMFcqIy69dBpr7syYiK9mAzvOhSDiPzzMazzzD2O3zljDYqRnFo5oosfAEgZR EIQIGqV1vHcyfTYaHqT9ap3Qoc7Gz2bJMxjcxYWN6Kb9wyLVQEnOdA5M0vxXSoq/ZtZu dtSvGcyJfDDkoLhQVimdQiZUabnHUmdMj1sDk= MIME-Version: 1.0 Received: by 10.224.60.5 with SMTP id n5mr6274244qah.288.1275683518340; Fri, 04 Jun 2010 13:31:58 -0700 (PDT) Received: by 10.229.99.67 with HTTP; Fri, 4 Jun 2010 13:31:58 -0700 (PDT) In-Reply-To: <4C093A5B.4040705@mtmary.edu> References: <4C093A5B.4040705@mtmary.edu> Date: Fri, 4 Jun 2010 15:31:58 -0500 Message-ID: From: Adam Vande More To: Peter Clark Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-questions@freebsd.org Subject: Re: Some GMirror questions. 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, 04 Jun 2010 20:31:59 -0000 I think you are making this harder than is needs to be. When in doubt defe= r to the Handbook and the man pages. This also a good page http://onlamp.com/pub/a/bsd/2005/11/10/FreeBSD_Basics.html Lastly, I know at one point the 'load' algorithm had some performance > problems and people were saying to only use 'round-robin'. It seems as > though some code was committed back in Dec 2009 to fix it's this. Is ther= e a > practical rule of thumb to using 'load' vs 'round-robin'? Use load. http://www.freebsd.org/cgi/query-pr.cgi?pr=3D113885 > Is this an accurate way to look at it? > "Round-robin because if you have two disks in a mirror, they=92re both un= der > the same 'load' constraints, and it is best to KISS." > No. round-robin is a simple algorithm which alternates drive requests. Als= o two identical HD's may be mirrored but they will not really ever be same state in terms of caching, performance, etc. --=20 Adam Vande More