From owner-freebsd-fs@FreeBSD.ORG Wed Jun 12 11:40:34 2013 Return-Path: Delivered-To: freebsd-fs@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by hub.freebsd.org (Postfix) with ESMTP id 39B6C4AC for ; Wed, 12 Jun 2013 11:40:34 +0000 (UTC) (envelope-from feld@feld.me) Received: from out3-smtp.messagingengine.com (out3-smtp.messagingengine.com [66.111.4.27]) by mx1.freebsd.org (Postfix) with ESMTP id 0FD5A1383 for ; Wed, 12 Jun 2013 11:40:33 +0000 (UTC) Received: from compute2.internal (compute2.nyi.mail.srv.osa [10.202.2.42]) by gateway1.nyi.mail.srv.osa (Postfix) with ESMTP id 1D7D6202B4 for ; Wed, 12 Jun 2013 07:40:33 -0400 (EDT) Received: from frontend1.nyi.mail.srv.osa ([10.202.2.160]) by compute2.internal (MEProxy); Wed, 12 Jun 2013 07:40:33 -0400 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d=feld.me; h= content-type:to:subject:references:date:mime-version :content-transfer-encoding:from:message-id:in-reply-to; s= mesmtp; bh=MqodeHbV4GO4rRE2iQzLLhCKKRo=; b=fJGym8QTZVVQzeTF88IeB efygSQzPvPGWgxKUyirhfujGYSTxgDXK3MKGJT60XAgbSIaqFCT5HpsURPuWo219 WW05ch1viVxTuTSHA6/3B3qMXazCiRlA72rdxrkUmahT3s53HaFVlrw2B3nKRVEe M+/MVn+wlol/3/xQzgiTtA= DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; d= messagingengine.com; h=content-type:to:subject:references:date :mime-version:content-transfer-encoding:from:message-id :in-reply-to; s=smtpout; bh=MqodeHbV4GO4rRE2iQzLLhCKKRo=; b=LSz2 iGPrzqJRGBBN/hPjlirxb9zTAkpZ/C66BY0a0+ICxBhnuwb3mEZKKIoELRC0cMtR rrtXIqCfN0MDUYTR1qdk/YkhLSxTlxyYnG6OvxBffEmYRkFCQtV4UY839buicS1q 71G3YVcyKDOx+3tKJUBbfCZRSUgPfphNUmehiCI= X-Sasl-enc: LAyeIfZX08QsWlq/ru4x6uK3D9LLy5QwEfPn9Ufsd6Bb 1371037232 Received: from markf.office.supranet.net (unknown [66.170.8.18]) by mail.messagingengine.com (Postfix) with ESMTPA id DB7B4C00E81 for ; Wed, 12 Jun 2013 07:40:32 -0400 (EDT) Content-Type: text/plain; charset=us-ascii; format=flowed; delsp=yes To: freebsd-fs@freebsd.org Subject: Re: An order of magnitude higher IOPS needed with ZFS than UFS References: <51B79023.5020109@fsn.hu> Date: Wed, 12 Jun 2013 06:40:32 -0500 MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: "Mark Felder" Message-ID: In-Reply-To: <51B79023.5020109@fsn.hu> User-Agent: Opera Mail/12.15 (FreeBSD) X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 12 Jun 2013 11:40:34 -0000 On Tue, 11 Jun 2013 16:01:23 -0500, Attila Nagy wrote: > BTW, the file systems are 77-78% full according to df (so ZFS holds > more, because UFS is -m 8). ZFS write performance can begin to drop pretty badly when you get around 80% full. I've not seen any benchmarks showing an improvement with a very fast and large ZIL or tons of memory, but I'd expect that would help significantly. Just note that you're right at the edge where performance gets impacted.