From owner-freebsd-fs@freebsd.org Sat Oct 3 23:49:25 2015 Return-Path: Delivered-To: freebsd-fs@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 23060A0EF03 for ; Sat, 3 Oct 2015 23:49:25 +0000 (UTC) (envelope-from thomasrcurry@gmail.com) Received: from mail-ig0-x229.google.com (mail-ig0-x229.google.com [IPv6:2607:f8b0:4001:c05::229]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id E1F5B1D4B for ; Sat, 3 Oct 2015 23:49:24 +0000 (UTC) (envelope-from thomasrcurry@gmail.com) Received: by igcrk20 with SMTP id rk20so39679138igc.1 for ; Sat, 03 Oct 2015 16:49:23 -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=EnPeJjIqapDULhg3XJYkFOv0VInaqE2lGms1VKw3eXg=; b=0vPH9FoN0OPRdiP/BYeGqotdclFmuILoMHiRc/6RRwEuU5KUGpdofyhjfTpyANt5fy 28zNQk7TH2oQ1Fs5povx2Q0kkcYKfrx/JUtQMqAxOa7S6DyJJilg5/CdgdWAQzMEAUMO +VAJSBbLqMVc7uPU5Y13BUwa1ZN89LxN6BjrujRxPebLNRubOedoEMKrxYOaIL8++hxg m50vm0VPPTyFPYbeZaK5zknj0Yxby81VDFTMO1KI9KrTqPVREd7hJbg0xKmoA/znqpk8 ztM/eL3406LaBHM/b3B14vN6olgtiWiuoVSvJZUI+vvXonclFvpvg9qOPJIO4k8KGXYs 9Dxw== MIME-Version: 1.0 X-Received: by 10.50.62.46 with SMTP id v14mr3761202igr.79.1443916163687; Sat, 03 Oct 2015 16:49:23 -0700 (PDT) Received: by 10.107.4.72 with HTTP; Sat, 3 Oct 2015 16:49:23 -0700 (PDT) In-Reply-To: <560E3F32.5060600@digiware.nl> References: <56050EFC.1000303@digiware.nl> <1443179614.5271.42.camel@data-b104.adm.slu.se> <5606EBEA.2090103@digiware.nl> <560E3F32.5060600@digiware.nl> Date: Sat, 3 Oct 2015 19:49:23 -0400 Message-ID: Subject: Re: ZFS, Zvol, iSCSI and windows From: Tom Curry To: Willem Jan Withagen Cc: "freebsd-fs@freebsd.org" Content-Type: text/plain; charset=UTF-8 X-Content-Filtered-By: Mailman/MimeDel 2.1.20 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: Sat, 03 Oct 2015 23:49:25 -0000 On Fri, Oct 2, 2015 at 4:24 AM, Willem Jan Withagen wrote: > > So the moral of the story: > It is not always wise to match NTFS blocksize with the ZVOL blocksize. > > As for possible performance penalties on the Windows side.... > It is hard to find a niche and sensible disk tester. > > Using the error scanner from HDtune, performance has dropped a tiny bit. > I'm seeing a 1000 IOPS and 30Mbyte/sec of throuput. > This is on a 2* vdev 6* disk raidz2 volume. > > --WjW > Well if space efficiency is the goal then the moral of the story should be when using a fixed block/stripe size (as is the case with a zvol) make sure the size is at least as large as the sum of all non parity/mirror disks in a vdev. I think this holds true for any vdev configuration, be it a stripe, mirror or parity. As for the NTFS cluster size, in my travels I haven't been able to notice any real performance or efficiency difference when changing the cluster size. Perhaps a little variance at extremes, but nothing worth getting excited over.