From owner-freebsd-fs@FreeBSD.ORG Wed Jun 12 14:52:44 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 D4E0E8DE for ; Wed, 12 Jun 2013 14:52:44 +0000 (UTC) (envelope-from amvandemore@gmail.com) Received: from mail-pa0-x235.google.com (mail-pa0-x235.google.com [IPv6:2607:f8b0:400e:c03::235]) by mx1.freebsd.org (Postfix) with ESMTP id B397F117F for ; Wed, 12 Jun 2013 14:52:44 +0000 (UTC) Received: by mail-pa0-f53.google.com with SMTP id tj12so4953867pac.40 for ; Wed, 12 Jun 2013 07:52:43 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; bh=M2sQqeX5UwmfBtYtkhEwPwU8b2dVxUJm0BCuAvYFtz0=; b=OaswgK0E744eT/uWgAQIGtBy9EzaHoz8LBS0j067xfOAviYZy9JKc9IINhyhrBNK1v Lh3Ggl+r4tk7/t9ohtAAzKfkxfVFLy2ma5Onj+VBsBTmWwCkUCirx4WmjYbdLJ59VOvJ mEtgKGep89z2Sgioc1zokwHGLk+rXxDUGtttLgOlYsC/yxSW1/ZpmBZBMZumV8PriS4/ zZ5fhWbz9PNJ9n6zj9sQWCdEv5WvBB624MRAR4e5tk/12IJxLnNjxEzzX5XvkeNFgnXb FdkMWN3+Yf+bSYdCRgoZmUBehUtW9hkl49iS7T8jQEMIKG2BznIiO3W03nF6/vJyiE6j bRaw== MIME-Version: 1.0 X-Received: by 10.68.203.161 with SMTP id kr1mr19688590pbc.192.1371048763895; Wed, 12 Jun 2013 07:52:43 -0700 (PDT) Received: by 10.70.31.195 with HTTP; Wed, 12 Jun 2013 07:52:43 -0700 (PDT) In-Reply-To: <20130612114937.GA13688@icarus.home.lan> References: <51B79023.5020109@fsn.hu> <20130612114937.GA13688@icarus.home.lan> Date: Wed, 12 Jun 2013 09:52:43 -0500 Message-ID: Subject: Re: An order of magnitude higher IOPS needed with ZFS than UFS From: Adam Vande More To: Jeremy Chadwick Content-Type: text/plain; charset=ISO-8859-1 X-Content-Filtered-By: Mailman/MimeDel 2.1.14 Cc: freebsd-fs 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 14:52:44 -0000 On Wed, Jun 12, 2013 at 6:49 AM, Jeremy Chadwick wrote: > Mark, do you have any references for this? I'd love to learn/read more > about this engineering/design aspect (I won't say flaw, I'll just say > aspect) to ZFS, as it's the first I've heard of it. Recently, I dd'ed out the free space on a ZFS volume. The last few MB's took like an hour and io seemed to drop exponentially once past 80% or so. Nothing to do with SSD's -- Adam Vande More