From owner-freebsd-fs@freebsd.org Wed Apr 27 12:05:16 2016 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 8D03EB1D45E for ; Wed, 27 Apr 2016 12:05:16 +0000 (UTC) (envelope-from 000.fbsd@quip.cz) Received: from elsa.codelab.cz (elsa.codelab.cz [94.124.105.4]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 3170311D7 for ; Wed, 27 Apr 2016 12:05:15 +0000 (UTC) (envelope-from 000.fbsd@quip.cz) Received: from elsa.codelab.cz (localhost [127.0.0.1]) by elsa.codelab.cz (Postfix) with ESMTP id 2740F28416; Wed, 27 Apr 2016 14:05:14 +0200 (CEST) Received: from illbsd.quip.test (ip-86-49-16-209.net.upcbroadband.cz [86.49.16.209]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by elsa.codelab.cz (Postfix) with ESMTPSA id 40E6028412; Wed, 27 Apr 2016 14:05:12 +0200 (CEST) Message-ID: <5720AAF8.4090900@quip.cz> Date: Wed, 27 Apr 2016 14:05:12 +0200 From: Miroslav Lachman <000.fbsd@quip.cz> User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:35.0) Gecko/20100101 Firefox/35.0 SeaMonkey/2.32 MIME-Version: 1.0 To: Andy Farkas , 'PK1048' CC: freebsd-fs@freebsd.org Subject: Re: How to speed up slow zpool scrub? References: <698816653.2698619.1461685653634.JavaMail.yahoo.ref@mail.yahoo.com> <698816653.2698619.1461685653634.JavaMail.yahoo@mail.yahoo.com> <571F9897.2070008@quip.cz> <571FEB34.7040305@andyit.com.au> <56C0A956-F134-4A8D-A8B6-B93DCA045BE4@pk1048.com> <084201d1a03e$d2158fe0$7640afa0$@andyit.com.au> In-Reply-To: <084201d1a03e$d2158fe0$7640afa0$@andyit.com.au> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 27 Apr 2016 12:05:16 -0000 Andy Farkas wrote on 04/27/2016 06:39: >> -----Original Message----- >> From: PK1048 [mailto:paul@pk1048.com] >> Sent: Wednesday, 27 April 2016 12:34 PM >> To: Andy Farkas >> Cc: freebsd-fs@freebsd.org >> Subject: Re: How to speed up slow zpool scrub? >> >> ... >> Scrubs (and resilver) operations are essentially all random I/O. Those >> drives are low end, low performance, desktop drives. > > Yes, the system is an old low end, low performance desktop. That was > my point, that it took 25 hours to scrub 7.52T and not 4 days like the > OP is saying. Thank you for output of your zpool scrub. It is definitely faster than mine. To: Paul pk1048 Mine scrub does not repair anything. Drives are OK (in SMART). CPU is about 70%-90% idle during scrub + rsync backup and drives are about 60%-70% busy according to iostat: root@kiwi ~/# iostat -x -w 10 ada0 ada1 ada2 ada3 extended device statistics device r/s w/s kr/s kw/s qlen svc_t %b ada0 70.1 17.9 1747.0 802.4 0 7.0 24 ada1 70.1 17.9 1747.1 802.4 0 7.0 25 ada2 66.9 17.1 1686.4 791.3 4 6.5 23 ada3 66.9 16.9 1686.3 790.1 2 6.6 23 extended device statistics device r/s w/s kr/s kw/s qlen svc_t %b ada0 93.6 13.0 576.4 244.0 0 21.6 70 ada1 98.6 12.9 587.2 246.4 2 20.5 71 ada2 87.9 15.3 566.0 242.4 3 20.5 67 ada3 84.9 14.5 549.2 237.2 3 20.4 66 extended device statistics device r/s w/s kr/s kw/s qlen svc_t %b ada0 98.7 42.5 1924.7 2536.3 1 26.3 86 ada1 99.1 45.5 1931.5 2671.5 1 23.8 87 ada2 94.2 44.9 1840.7 2720.3 0 20.1 76 ada3 93.6 42.7 1807.9 2607.1 0 18.7 75 extended device statistics device r/s w/s kr/s kw/s qlen svc_t %b ada0 108.2 28.2 1092.6 1316.6 2 17.3 68 ada1 101.6 26.3 1053.8 1183.4 3 15.5 67 ada2 98.6 26.0 1000.2 1126.2 2 12.2 57 ada3 104.0 24.0 1015.8 1080.6 3 14.1 60 extended device statistics device r/s w/s kr/s kw/s qlen svc_t %b ada0 116.0 18.5 821.8 807.8 0 12.9 62 ada1 117.2 18.5 822.2 807.0 0 13.5 63 ada2 110.8 20.9 743.0 803.8 0 11.1 58 ada3 108.2 20.0 688.2 755.0 2 11.3 55 extended device statistics device r/s w/s kr/s kw/s qlen svc_t %b ada0 121.8 16.6 602.1 526.9 3 9.2 52 ada1 122.2 16.5 606.9 528.5 4 9.8 54 ada2 117.0 14.6 601.7 524.9 2 11.3 60 ada3 120.6 13.5 610.1 491.3 0 11.4 61 I really don't know why it cannot go faster if nothing is loaded for 100%. Miroslav Lachman