From owner-freebsd-fs@FreeBSD.ORG Mon Jun 22 22:37:07 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 25E522AE for ; Mon, 22 Jun 2015 22:37:07 +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 03DF7C8 for ; Mon, 22 Jun 2015 22:37:06 +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 F08D83F760; Mon, 22 Jun 2015 18:37:05 -0400 (EDT) Message-ID: <55888E0D.6040704@sneakertech.com> Date: Mon, 22 Jun 2015 18:37:01 -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: kpneal@pobox.com CC: FreeBSD FS Subject: Re: ZFS raid write performance? References: <5587C3FF.9070407@sneakertech.com> <5587C97F.2000407@delphij.net> <55887810.3080301@sneakertech.com> <20150622221422.GA71520@neutralgood.org> In-Reply-To: <20150622221422.GA71520@neutralgood.org> 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: Mon, 22 Jun 2015 22:37:07 -0000 >>> a single hard drive won't do much beyond 100MB/s (maybe >>> 120MB/s max) for sequential 128kB blocks, so that "landing pad" would >>> probably not very helpful assuming you can saturate your GigE network >> >> Wait, I'm confused. A single GigE has a theoretical max of like >> 100mb/sec. That would imply the drive is probably about the same speed? > > You won't get the theoretical max what with the overhead of Ethernet > packets, TCP/IP overhead, and SMB protocol overhead. Right, I know that, that's why I don't understand what Xin Li was trying to say. I guess a better way to word the question is: would a raidzX using generic drives, samba, and 500mb-4gb files be notably slower at writing than ~70mb/sec. I have a feeling not, but I wanted to double check.