From owner-freebsd-questions@freebsd.org Wed Oct 21 13:22:01 2015 Return-Path: Delivered-To: freebsd-questions@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 9ED06A1BC22 for ; Wed, 21 Oct 2015 13:22:01 +0000 (UTC) (envelope-from wam@hiwaay.net) Received: from fly.hiwaay.net (fly.hiwaay.net [216.180.54.1]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 6862D11D1 for ; Wed, 21 Oct 2015 13:22:00 +0000 (UTC) (envelope-from wam@hiwaay.net) Received: from kabini1.local (dynamic-216-186-213-32.knology.net [216.186.213.32] (may be forged)) (authenticated bits=0) by fly.hiwaay.net (8.13.8/8.13.8/fly) with ESMTP id t9LDLvGT023881 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO) for ; Wed, 21 Oct 2015 08:21:58 -0500 Subject: Re: Post install FWIW References: <56265636.4050208@hiwaay.net> <562685CE.5050309@sneakertech.com> <5626BAB6.4070304@hiwaay.net> <20151021105210.GA31309@neutralgood.org> Cc: freebsd-questions@freebsd.org From: "William A. Mahaffey III" Message-ID: <56279175.6000006@hiwaay.net> Date: Wed, 21 Oct 2015 08:27:27 -0453.75 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 MIME-Version: 1.0 In-Reply-To: <20151021105210.GA31309@neutralgood.org> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 21 Oct 2015 13:22:01 -0000 On 10/21/15 05:58, kpneal@pobox.com wrote: > On Tue, Oct 20, 2015 at 05:11:12PM -0453, William A. Mahaffey III wrote: >> On 10/20/15 13:26, Quartz wrote: >>>> When I dd'ed /dev/zero to (re-) initialize the individual >>>> drives during install, I saw 125-ish MB/s per drive, so this is 90-ish % >>>> efficient for this write. >>> Do remember that using dd to estimate disk speeds is tricky since its >>> write pattern is somewhat non-standard. You should try a more 'real >>> world' test like rsyncing a bunch of random crap with differing sizes. >>> _______________________________________________ >>> freebsd-questions@freebsd.org mailing list >>> https://lists.freebsd.org/mailman/listinfo/freebsd-questions >>> To unsubscribe, send any mail to >>> "freebsd-questions-unsubscribe@freebsd.org" >>> >> >> *Agreed*, that's why I called it 'light benchmarking'. I will be alert >> to more data as time goes on, but this looked so promising I decided to >> spread the love, so to speak .... > Does this system have the optimization turned on where writes of all > zeros get detected and turned into just a single block on disk? > > Maybe I'm thinking of a dedup option in which case you can ignore me. Very good question, I wouldn't know, I made very few changes from the wiki page during the install. How would I check on that ? TIA & have a good one. -- William A. Mahaffey III ---------------------------------------------------------------------- "The M1 Garand is without doubt the finest implement of war ever devised by man." -- Gen. George S. Patton Jr.