From owner-freebsd-questions@FreeBSD.ORG Sun Jun 26 05:25:41 2011 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 6A7FA106566C for ; Sun, 26 Jun 2011 05:25:41 +0000 (UTC) (envelope-from jrisom@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 2A9808FC12 for ; Sun, 26 Jun 2011 05:25:40 +0000 (UTC) Received: by iyb11 with SMTP id 11so4652880iyb.13 for ; Sat, 25 Jun 2011 22:25:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:message-id:date:from:user-agent:mime-version:to :cc:subject:references:in-reply-to:content-type :content-transfer-encoding; bh=vqLtMvAroolPtCfngqmFDQ8RjjMnuyxi+XxLzzrHp34=; b=ZSSHV7vUU9z51WOC/9r9TkBUmjav9oNZ8tyiBORw5PlKSgfgW+c1L4EeqgGJTbtrA2 xTIe2RlxRes2XAtziJ3dm3/Gc9CdiPwaNl0saII5TbK53eemvccWl/BB+M2GemdGkL1G TFWztu9s04pKBAT93zBK3/XbvU2Sg4sSNrRjg= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:cc:subject :references:in-reply-to:content-type:content-transfer-encoding; b=rfX+nqyVsq9hgzrFpZkbOe2ecnxVph+xlmFxsrECfSq+jpNzrNlObFdptQXfW7gfVA KG1uFxfxzaZw5pfgl0h6onE2bVa73LLLxpSVRnhT0imvcHObRnuDmfCpwDQmz+r+R7an 7FUy+4yMdVW98Yw/8+wVLZrl7vanhjK77x49s= Received: by 10.231.74.2 with SMTP id s2mr4686349ibj.8.1309065939578; Sat, 25 Jun 2011 22:25:39 -0700 (PDT) Received: from [192.168.1.6] (c-98-212-201-29.hsd1.il.comcast.net [98.212.201.29]) by mx.google.com with ESMTPS id in11sm2357542ibb.22.2011.06.25.22.25.38 (version=SSLv3 cipher=OTHER); Sat, 25 Jun 2011 22:25:39 -0700 (PDT) Message-ID: <4E06C2D1.4050601@gmail.com> Date: Sun, 26 Jun 2011 00:25:37 -0500 From: Joshua Isom User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.2.18) Gecko/20110616 Lightning/1.0b2 Thunderbird/3.1.11 MIME-Version: 1.0 To: Damien Fleuriot References: <4E06180F.7090409@gmail.com> <16AE025C-EA55-45F3-8419-542228CE5AA4@my.gd> In-Reply-To: <16AE025C-EA55-45F3-8419-542228CE5AA4@my.gd> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: "freebsd-questions@freebsd.org" Subject: Re: Performance of a USB ZIL for ZFS 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: Sun, 26 Jun 2011 05:25:41 -0000 On 6/25/2011 9:32 PM, Damien Fleuriot wrote: > On 25 Jun 2011, at 19:17, Joshua Isom wrote: > >> I was wondering if anyone had tried using a decent USB flash drive for the ZIL. I know it'd be hard finding one fast enough, but some from patriot seem like they might be suitable for home use. Part of the idea is to just minimize hard drive thrashing and the wear and tear associated with it. If it helps prevent the drives from going bad, and doesn't hurt performance too bad all the better. But if it's going to hurt performance too much or not help prevent thrashing there isn't a point. >> _______________________________________________ >> freebsd-questions@freebsd.org mailing list >> http://lists.freebsd.org/mailman/listinfo/freebsd-questions >> To unsubscribe, send any mail to "freebsd-questions-unsubscribe@freebsd.org" > > > I stopped reading at the title. > The answer is no. > > Grab a SSD for $80-120ish. Perhaps it would have helped to read the email. Part of the concern is making sure the drives don't fail and not just throughput. Given that Kingston sells an SATA SSD for $40 that only gets writes at 30mb/s write, and some USB drives might get up to 20mb/s. If I get two drives and put them on different controllers, mirrored, I might get acceptable performance. I may still loose performance, but if my drives last a year longer, I can probably accept it. I'm ok with loosing some performance, but I just don't want it dragging down the system. And if it won't help the drives last longer there's no point.