From owner-freebsd-hardware@FreeBSD.ORG Fri Jan 9 08:46:58 2009 Return-Path: Delivered-To: freebsd-hardware@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id AD9091065675; Fri, 9 Jan 2009 08:46:58 +0000 (UTC) (envelope-from kgysmits@gmail.com) Received: from fk-out-0910.google.com (fk-out-0910.google.com [209.85.128.184]) by mx1.freebsd.org (Postfix) with ESMTP id D50B18FC0A; Fri, 9 Jan 2009 08:46:57 +0000 (UTC) (envelope-from kgysmits@gmail.com) Received: by fk-out-0910.google.com with SMTP id k31so6149717fkk.11 for ; Fri, 09 Jan 2009 00:46:56 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:message-id:date:from:to :subject:cc:in-reply-to:mime-version:content-type:references; bh=6u/k8u1Jq+vGNREoamDRInJeIkllpxF5NuOZNvGuUjM=; b=krnMLAtzUhv23MqCJ6jZsfALPwdWYGwPcREXWmjnTQXXnV79vuVzMNkrEK7cXrB/Io opxOuRAwaluVvVaLXf+BVvBMdYlFUwao0b35BE3Ek6e6qmMCzvHnXaiTYId8Ww/GDTnA szSxRvn25bFRS55XQvr1LO8o7GSAyTy5rVIaY= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:to:subject:cc:in-reply-to:mime-version :content-type:references; b=D9SCdhdrEksQQzOvGgLWtcN4fpYTaoawHA150GSZiKniFLk72rwitVYUr3ES0Ksr1p r+j7B7dYCtU+jNQYX082u3TMT6XDYe4LK8cYVqcRb/vDeDFHSxdM41xJ/YwXHELKi8YT 1ZdgNPwSGRNdLi9z9KF7DZuQSRkIfhoF8jvN0= Received: by 10.223.111.211 with SMTP id t19mr1365569fap.64.1231490816489; Fri, 09 Jan 2009 00:46:56 -0800 (PST) Received: by 10.223.108.136 with HTTP; Fri, 9 Jan 2009 00:46:56 -0800 (PST) Message-ID: Date: Fri, 9 Jan 2009 09:46:56 +0100 From: "Koen Smits" To: fbsd@dannysplace.net In-Reply-To: <4966B6B1.8020502@dannysplace.net> MIME-Version: 1.0 References: <20081031033208.GA21220@icarus.home.lan> <491C5AA7.1030004@samsco.org> <491C9535.3030504@dannysplace.net> <4920E1DD.7000101@dannysplace.net> <20081117070818.GA22231@icarus.home.lan> <496549D9.7010003@dannysplace.net> <4966B6B1.8020502@dannysplace.net> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Content-Disposition: inline X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-fs@freebsd.org, Jeremy Chadwick , freebsd-hardware@freebsd.org Subject: Re: Areca vs. ZFS performance testing. X-BeenThere: freebsd-hardware@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: General discussion of FreeBSD hardware List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 09 Jan 2009 08:46:59 -0000 Those numbers are pretty good, right? Who needs onboard XOR anyway :) On Fri, Jan 9, 2009 at 03:30, Danny Carroll wrote: > Koen Smits wrote: > > My guess is it probably has to do with the way ZFS does cache flushes: > > > http://www.solarisinternals.com/wiki/index.php/ZFS_Evil_Tuning_Guide#Cache_Flushes > > It might be worth it to disable the forced flushing and test again, if > > you feel like it. > > I've just done this and the results are on the same page: > > http://www.dannysplace.net/quickweb/filesystem%20tests.htm > The Excel version is here: > > http://www.dannysplace.net/quickweb/filesystem%20tests.xls > > It is a major improvement but I do not know 100% for sure if the disks > are protected by the write cache/battery backup when in Passthrough mode. > > When creating a passthrough disk the "Volume Cache Mode" can be set to > "Write Back" or "Write Through". This makes me feel as though the cache > is being used and that when the cache is used, so is the BBU. But I > cannot be 100% sure. I will send an email to Areca support to ask. > > -D >