From owner-freebsd-fs@FreeBSD.ORG Tue Jun 23 18:50:55 2015 Return-Path: Delivered-To: freebsd-fs@nevdull.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 2430CC7A for ; Tue, 23 Jun 2015 18:50:55 +0000 (UTC) (envelope-from quartz@sneakertech.com) Received: from douhisi.pair.com (douhisi.pair.com [209.68.5.179]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id F3608FE8 for ; Tue, 23 Jun 2015 18:50:54 +0000 (UTC) (envelope-from quartz@sneakertech.com) Received: from [10.2.2.1] (pool-173-48-121-235.bstnma.fios.verizon.net [173.48.121.235]) by douhisi.pair.com (Postfix) with ESMTPSA id E79F83F6D9 for ; Tue, 23 Jun 2015 14:50:52 -0400 (EDT) Message-ID: <5589AA8C.30304@sneakertech.com> Date: Tue, 23 Jun 2015 14:50:52 -0400 From: Quartz User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.6; rv:10.0.2) Gecko/20120216 Thunderbird/10.0.2 MIME-Version: 1.0 To: freebsd-fs@freebsd.org Subject: Re: ZFS raid write performance? References: <5587C3FF.9070407@sneakertech.com> <5587C97F.2000407@delphij.net> <55887810.3080301@sneakertech.com> <20150622221422.GA71520@neutralgood.org> <55888E0D.6040704@sneakertech.com> <20150623002854.GB96928@neutralgood.org> <5588D291.4030806@sneakertech.com> <20150623042234.GA66734@neutralgood.org> <55897878.30708@kateley.com> In-Reply-To: <55897878.30708@kateley.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 23 Jun 2015 18:50:55 -0000 > Is it possible that the suggestion for the "landing pad" could be > recommending a smaller ssd pool? Then replicating back to a slower pool? It was for a single not-raid disk (then presumably rsyncing the files over to the pool, or something). The thought process seemed to be that a single disk always beat a raid-with-parity (ie; raid5, raidz2, etc) when it came to write speed. > This is another argument for Quartz to test like he(?) would use in > production. Yeah, it's just that that's not terribly convenient at the moment. I think I'll just toss another drive in there and do some limited testing when we start copying things over.