From owner-freebsd-fs@freebsd.org Thu Mar 25 15:34:51 2021 Return-Path: Delivered-To: freebsd-fs@mailman.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.nyi.freebsd.org (Postfix) with ESMTP id D072A5C19ED for ; Thu, 25 Mar 2021 15:34:51 +0000 (UTC) (envelope-from avg@FreeBSD.org) Received: from relay6-d.mail.gandi.net (relay6-d.mail.gandi.net [217.70.183.198]) (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 4F5q0q2vXpz3lxM for ; Thu, 25 Mar 2021 15:34:50 +0000 (UTC) (envelope-from avg@FreeBSD.org) X-Originating-IP: 195.64.148.76 Received: from [192.168.0.88] (unknown [195.64.148.76]) (Authenticated sender: andriy.gapon@uabsd.com) by relay6-d.mail.gandi.net (Postfix) with ESMTPSA id 5B8CBC0006; Thu, 25 Mar 2021 15:34:48 +0000 (UTC) Subject: Re: Scrub incredibly slow with 13.0-RC3 (as well as RC1 & 2) To: Matt Churchyard , Mathieu Chouquet-Stringer Cc: "freebsd-fs@freebsd.org" References: <202103221515.12MFFHRK015188@higson.cam.lispworks.com> <202103241230.12OCUqur030001@higson.cam.lispworks.com> <33eb78e2de404a77b271880dbee4c22e@SERVER.ad.usd-group.com> From: Andriy Gapon Message-ID: <13825648-7965-8a95-67a2-262cb50c2d71@FreeBSD.org> Date: Thu, 25 Mar 2021 17:34:47 +0200 User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:78.0) Gecko/20100101 Firefox/78.0 Thunderbird/78.8.1 MIME-Version: 1.0 In-Reply-To: <33eb78e2de404a77b271880dbee4c22e@SERVER.ad.usd-group.com> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 4F5q0q2vXpz3lxM X-Spamd-Bar: / Authentication-Results: mx1.freebsd.org; none X-Spamd-Result: default: False [0.00 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; TAGGED_RCPT(0.00)[freebsd]; ASN(0.00)[asn:29169, ipnet:217.70.176.0/20, country:FR] X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 25 Mar 2021 15:34:51 -0000 On 25/03/2021 10:55, Matt Churchyard wrote: > Just an a aside, I did post a message a few weeks ago with a similar problem > on 13 (as well as snapshot issues). Scrub seemed ok for a short while, but > then ground to a halt. It would take 10+ minutes to go 0.01%, with everything > appearing fairly idle. I finally gave up and stopped it after about 20 hours. > Moving to 12.2 and > rebuilding the pool, This could make a huge difference, though. Scrub performance significantly depends on the data layout. The more sequential it is the better. So, older (and more fragmented) pools are at disadvantage. > the system scrubbed the same data in > an hour, and I've just scrubbed the same system after a month of use with > about 4 times the data in 3 hours 20. As far as I'm aware, both should be > using effectively the same "new" scrub code. > > Will be interesting if you find a cause as I didn't get any response to what > for me was a complete showstopper for moving to 13. -- Andriy Gapon -- Andriy Gapon