From owner-freebsd-fs@freebsd.org Mon Aug 3 21:12:11 2020 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 A617A3A7556 for ; Mon, 3 Aug 2020 21:12:11 +0000 (UTC) (envelope-from spork@bway.net) Received: from smtp1.bway.net (smtp1.bway.net [216.220.96.27]) (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 4BL9Z30nB6z4PYM; Mon, 3 Aug 2020 21:12:10 +0000 (UTC) (envelope-from spork@bway.net) Received: from gaseousweiner.sporklab.com (pool-173-70-93-30.nwrknj.fios.verizon.net [173.70.93.30]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: spork@bway.net) by smtp1.bway.net (Postfix) with ESMTPSA id EBD5895897; Mon, 3 Aug 2020 17:12:09 -0400 (EDT) Content-Type: multipart/signed; boundary="Apple-Mail=_71218212-C9A8-468D-BD83-5DA65A9CB9FD"; protocol="application/pgp-signature"; micalg=pgp-sha256 Mime-Version: 1.0 (Mac OS X Mail 12.4 \(3445.104.15\)) Subject: Re: zfs scrub enable by default From: Charles Sprickman In-Reply-To: <24edb075-155c-439d-1ef5-541893036429@freebsd.org> Date: Mon, 3 Aug 2020 17:12:09 -0400 Cc: freebsd-fs@freebsd.org X-Mao-Original-Outgoing-Id: 618181929.277581-d530c6a94d4ae897b9d6e7e9501f221d Message-Id: <0E22A84A-DAAF-4651-865B-0AE038C7C3F4@bway.net> References: <24edb075-155c-439d-1ef5-541893036429@freebsd.org> To: Allan Jude X-Mailer: Apple Mail (2.3445.104.15) X-Rspamd-Queue-Id: 4BL9Z30nB6z4PYM X-Spamd-Bar: ---- X-Spamd-Result: default: False [-4.00 / 15.00]; ASN(0.00)[asn:8059, ipnet:216.220.96.0/19, country:US]; REPLY(-4.00)[] X-BeenThere: freebsd-fs@freebsd.org X-Mailman-Version: 2.1.33 Precedence: list List-Id: Filesystems List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 03 Aug 2020 21:12:11 -0000 --Apple-Mail=_71218212-C9A8-468D-BD83-5DA65A9CB9FD Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=utf-8 > On Aug 3, 2020, at 4:25 PM, Allan Jude wrote: >=20 > On 2020-08-03 12:10, Steve Wills wrote: >> Hi, >>=20 >> I wonder why we don't enable zfs periodic scrub by default? >>=20 >> = https://svnweb.freebsd.org/base/head/usr.sbin/periodic/periodic.conf?view=3D= markup#l162 >>=20 >>=20 >> Anyone happen to know? >>=20 >> Thanks, >> Steve >>=20 >> _______________________________________________ >> freebsd-fs@freebsd.org mailing list >> https://lists.freebsd.org/mailman/listinfo/freebsd-fs >> To unsubscribe, send any mail to "freebsd-fs-unsubscribe@freebsd.org" >=20 > I think switching this to on-by-default is a good thing. >=20 > To be clear, which the check is part of 'periodic daily', it only > triggers a scrub if it has been more than 35 days since the last = scrub. >=20 > FreeNAS already has does this, and that accounts for a large number of > FreeBSD ZFS deployments. >=20 > There is tuning you can do in ZFS to try to lessen the impact of a = scrub > on your production workloads. >=20 >=20 > The periodic script lets you select which pools to include (defaults = to > all), so you can tune it to only scrub your root pool every 35 days, = and > not the large pool that might take too long to scrub or whatever. It > also lets you set a different threshold for each pool. >=20 > So I don't see any reason not to enable it by default, and just = document > how to adjust it if people really need to disable it. Honestly, I = think > those who are disabling it are doing themselves a disservice. I 100% agree. I think often FreeBSD defaults tend to favor the = experienced user and throw the newbies under the bus. In this case there = were arguments against that amounted to =E2=80=9CWhat about people = running large production systems=E2=80=9D, to which my answer would be, = =E2=80=9CWhat about them? They are experienced, read all the mailing = lists, would know right away what was happening when they saw a scrub = running, and already know how to disable it and could make the case for = disabling or swapping in their own solution=E2=80=9D. Contrast with the random home user, noob, casual user who would likely = benefit from whatever data protection, pre-emptive failure notification, = etc. this would provide (for example I=E2=80=99ve had a scrub show me a = failing drive before SMART did). Charles >=20 > -- > Allan Jude >=20 --Apple-Mail=_71218212-C9A8-468D-BD83-5DA65A9CB9FD Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename=signature.asc Content-Type: application/pgp-signature; name=signature.asc Content-Description: Message signed with OpenPGP -----BEGIN PGP SIGNATURE----- Comment: GPGTools - http://gpgtools.org iQEzBAEBCAAdFiEECbwhUg0jlYPK5QaKiZUhnP6GpPYFAl8ofakACgkQiZUhnP6G pPbhfwgAsVMetrmx5pgpt4V0oRElZffcMtUdvSYh5gWEW6vESu+rBdScR2tqEXwG pjlmhg9rZBnRdHKWe4NZQ3S7GHTSnr4jK60tkpoVzy4zdPNiFOkl1MKOsyZzQPfC 6fGT1bfEfcMPKA5QrwGU6hJ4PoB7XnLPeFwZ91Ilp+tnj9odfSo0tbAAjHCWe+rR mgN1Ey5MGOnhNw3ey+cn6YKqffGYsns32dwTaLnV77yRFkQS1Tj+DMnkpFfTQf43 CocG1ooPnr7+1LrtR26qzy8yWF1fyxxwDbP/MGXsfvIv/cHKJuD30KxXT1Q2qDND xOno5tnFtlNLBLIs9EakWFXv0uHTfQ== =yjDH -----END PGP SIGNATURE----- --Apple-Mail=_71218212-C9A8-468D-BD83-5DA65A9CB9FD--