From owner-freebsd-stable@freebsd.org Fri May 10 00:57:22 2019 Return-Path: Delivered-To: freebsd-stable@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id E05711592ADC for ; Fri, 10 May 2019 00:57:21 +0000 (UTC) (envelope-from michelle@sorbs.net) Received: from hades.sorbs.net (hades.sorbs.net [72.12.213.40]) by mx1.freebsd.org (Postfix) with ESMTP id 5BD068959B; Fri, 10 May 2019 00:57:19 +0000 (UTC) (envelope-from michelle@sorbs.net) MIME-version: 1.0 Content-type: text/plain; charset=utf-8 Received: from [10.10.0.230] (gate.mhix.org [203.206.128.220]) by hades.sorbs.net (Oracle Communications Messaging Server 7.0.5.29.0 64bit (built Jul 9 2013)) with ESMTPSA id <0PR900J7IKMR1100@hades.sorbs.net>; Thu, 09 May 2019 18:11:18 -0700 (PDT) Sun-Java-System-SMTP-Warning: Lines longer than SMTP allows found and truncated. Subject: Re: ZFS... From: Michelle Sullivan X-Mailer: iPad Mail (16A404) In-reply-to: Date: Fri, 10 May 2019 10:57:13 +1000 Cc: Miroslav Lachman <000.fbsd@quip.cz>, FreeBSD-STABLE Mailing List , Dimitry Andric Content-transfer-encoding: quoted-printable Message-id: <40021BE2-965B-4B37-969F-5391D5B931F7@sorbs.net> References: <30506b3d-64fb-b327-94ae-d9da522f3a48@sorbs.net> <5ED8BADE-7B2C-4B73-93BC-70739911C5E3@sorbs.net> <2e4941bf-999a-7f16-f4fe-1a520f2187c0@sorbs.net> <20190430102024.E84286@mulder.mintsol.com> <41FA461B-40AE-4D34-B280-214B5C5868B5@punkt.de> <20190506080804.Y87441@mulder.mintsol.com> <08E46EBF-154F-4670-B411-482DCE6F395D@sorbs.net> <33D7EFC4-5C15-4FE0-970B-E6034EF80BEF@gromit.dlib.vt.edu> <7D18A234-E7BF-4855-BD51-4AE2253DB1E4@sorbs.net> <805ee7f1-83f6-c59e-8107-4851ca9fce6e@quip.cz> <5de7f3d3-b34c-0382-b7d4-b7e38339649b@quip> To: Alan Somers X-Rspamd-Queue-Id: 5BD068959B X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org; spf=pass (mx1.freebsd.org: domain of michelle@sorbs.net designates 72.12.213.40 as permitted sender) smtp.mailfrom=michelle@sorbs.net X-Spamd-Result: default: False [-2.03 / 15.00]; ARC_NA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; NEURAL_HAM_MEDIUM(-0.68)[-0.677,0]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_THREE(0.00)[4]; R_SPF_ALLOW(-0.20)[+a:hades.sorbs.net]; NEURAL_HAM_LONG(-1.00)[-0.996,0]; MIME_GOOD(-0.10)[text/plain]; DMARC_NA(0.00)[sorbs.net]; TO_MATCH_ENVRCPT_SOME(0.00)[]; TO_DN_ALL(0.00)[]; MX_GOOD(-0.01)[cached: battlestar.sorbs.net]; NEURAL_HAM_SHORT(-0.29)[-0.288,0]; RCVD_IN_DNSWL_NONE(0.00)[40.213.12.72.list.dnswl.org : 127.0.10.0]; SUBJ_ALL_CAPS(0.45)[6]; IP_SCORE(-0.31)[ip: (-0.76), ipnet: 72.12.192.0/19(-0.40), asn: 11114(-0.31), country: US(-0.06)]; RCVD_NO_TLS_LAST(0.10)[]; FROM_EQ_ENVFROM(0.00)[]; R_DKIM_NA(0.00)[]; MIME_TRACE(0.00)[0:+]; ASN(0.00)[asn:11114, ipnet:72.12.192.0/19, country:US]; MID_RHS_MATCH_FROM(0.00)[]; RCVD_COUNT_TWO(0.00)[2] X-BeenThere: freebsd-stable@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Production branch of FreeBSD source code List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 10 May 2019 00:57:22 -0000 Michelle Sullivan http://www.mhix.org/ Sent from my iPad > On 09 May 2019, at 22:50, Alan Somers wrote: >=20 >> On Thu, May 9, 2019 at 5:37 AM Miroslav Lachman <000.fbsd@quip.cz> wrote:= >>=20 >> Dimitry Andric wrote on 2019/05/09 13:02: >>> On 9 May 2019, at 10:32, Miroslav Lachman <000.fbsd@quip.cz> wrote: >>=20 >> [...] >>=20 >>>> Disks are OK, monitored by smartmontools. There is nothing odd, just th= e long long scrubs. This machine was started with 4x 1TB (now 4x 4TB) and sc= rub was slow with 1TB disks too. This machine - HP ML110 G8) was my first ma= chine with ZFS. If I remember it well it was FreeBSD 7.0, now running 11.2. S= crub was / is always about one week. (I tried some sysctl tuning without muc= h gain) >>>=20 >>> Unfortunately https://svnweb.freebsd.org/changeset/base/339034, which >>> greatly speeds up scrubs and resilvers, was not in 11.2 (since it was >>> cut at r334458). >>>=20 >>> If you could update to a more recent snapshot, or try the upcoming 11.3 >>> prereleases, you will hopefully see much shorter scrub times. >>=20 >> Thank you. I will try 11-STABLE / 11.3-PRERELEASE soon and let you know >> about the difference. >>=20 >> Kind regards >> Miroslav Lachman >=20 > On 11.3 and even much older releases, you can greatly speed up scrub > and resilver by tweaking some sysctls. If you have spinning rust, > raise vfs.zfs.top_maxinflight so they'll do fewer seeks. I used to > set it to 8192 on machines with 32GB of RAM. Raising > vfs.zfs.resilver_min_time_ms to 5000 helps a little, too. I tried this, but I found that whilst it could speed up the resilver (and sc= rubs) by as much as 25% it also had a performance hit were reads (particular= ly streaming video - which is what my server mostly did) would =E2=80=9Cpaus= e=E2=80=9D and =E2=80=9Cstutter=E2=80=9D .. the balance came when I brought i= t back to around 200 * 15) . It would still stutter when running multiple streams (to the point of heavy l= oad) but that was kinda expected... I tried to keep the load distributed off= it and let the other front end servers stream and it seemed to result in a h= ealthy balance. >=20 > -Alan > _______________________________________________ > freebsd-stable@freebsd.org mailing list > https://lists.freebsd.org/mailman/listinfo/freebsd-stable > To unsubscribe, send any mail to "freebsd-stable-unsubscribe@freebsd.org"