From owner-freebsd-stable@FreeBSD.ORG Tue Feb 8 12:43:21 2011 Return-Path: Delivered-To: freebsd-stable@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id C23B4106564A for ; Tue, 8 Feb 2011 12:43:21 +0000 (UTC) (envelope-from jyavenard@gmail.com) Received: from mail-iy0-f182.google.com (mail-iy0-f182.google.com [209.85.210.182]) by mx1.freebsd.org (Postfix) with ESMTP id 7543C8FC08 for ; Tue, 8 Feb 2011 12:43:21 +0000 (UTC) Received: by iyb26 with SMTP id 26so5753503iyb.13 for ; Tue, 08 Feb 2011 04:43:20 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:in-reply-to:references:date :message-id:subject:from:to:cc:content-type :content-transfer-encoding; bh=FKv/yb72F5R5iE344dvqqFsTHVJSy21QZMmalmBXt9M=; b=aoJ+tu/fkZC2XKPYYzoC+YU7bMHrn1/PieaBjhdO64Jc3FPIJXU+fj6L3AZcBw2fF+ rf+2mejINoEunGp/Zn9HepWmWgHU6OPeeU+3x/FhneKLYumbxy+HkUmtIEz0GA/oRhGK WYmsqatlgcWLLSvD8+MXqVNViP+8v7PThhxu8= 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:content-transfer-encoding; b=RIm/oVIkKcXktQoXrqJEZCL66PkIeeT+ct/5vr7crC5SGe4xqGxQaG+XgqB6sVfl3d OZPH+67Kg25v1nIeF3nQCzl8uuvyRhmiJK5pxDEY95BeqdkYEDppUZsnzOkrlCfODRDv 7uxYrhPQupqyrJcJVQXQFN+VMzehWKwZhZphE= MIME-Version: 1.0 Received: by 10.42.176.134 with SMTP id be6mr1113777icb.82.1297169000216; Tue, 08 Feb 2011 04:43:20 -0800 (PST) Received: by 10.42.165.66 with HTTP; Tue, 8 Feb 2011 04:43:20 -0800 (PST) In-Reply-To: <20110207090347.GB20545@icarus.home.lan> References: <1297026074.23922.8.camel@ubuntu> <20110207045501.GA15568@icarus.home.lan> <20110207090347.GB20545@icarus.home.lan> Date: Tue, 8 Feb 2011 23:43:20 +1100 Message-ID: From: Jean-Yves Avenard To: Jeremy Chadwick Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Cc: Greg Bonett , Zaphod Beeblebrox , freebsd-stable Subject: Re: 8.1 amd64 lockup (maybe zfs or disk related) X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 08 Feb 2011 12:43:21 -0000 On 7 February 2011 20:03, Jeremy Chadwick wrote: > They're discussed practically on a monthly basis on the mailing lists > (either freebsd-fs or freebsd-stable). =A0Keeping track of them is almost > impossible at this point, which is also probably why the Wiki is > outdated. I like Sun's take on the matter: http://www.solarisinternals.com/wiki/index.php/ZFS_Evil_Tuning_Guide#Tuning= _is_Evil "Tuning is often evil and should rarely be done. First, consider that the default values are set by the people who know the most about the effects of the tuning on the software that they supply. If a better value exists, it should be the default. While alternative values might help a given workload, it could quite possibly degrade some other aspects of performance. Occasionally, catastrophically so. " Which I thing summarise perfectly ZFS "tuning". If you want to know 20 differents opinions on how zfs needs to be tuned; talk to 20 different people. Everyone has their own ideas on how it should be done ; believe a particular setting made things better. I tried them all I could read here, none of them make much significant difference, and and when they do, usually it's just for the worse.