From owner-freebsd-geom@FreeBSD.ORG Thu Feb 28 17:02:09 2013 Return-Path: Delivered-To: freebsd-geom@freebsd.org Received: from mx1.freebsd.org (mx1.FreeBSD.org [8.8.178.115]) by hub.freebsd.org (Postfix) with ESMTP id 999B37B5 for ; Thu, 28 Feb 2013 17:02:09 +0000 (UTC) (envelope-from gcubfg-freebsd-geom@m.gmane.org) Received: from plane.gmane.org (plane.gmane.org [80.91.229.3]) by mx1.freebsd.org (Postfix) with ESMTP id 3C0DD1FA for ; Thu, 28 Feb 2013 17:02:09 +0000 (UTC) Received: from list by plane.gmane.org with local (Exim 4.69) (envelope-from ) id 1UB6sA-000897-9w for freebsd-geom@freebsd.org; Thu, 28 Feb 2013 18:02:22 +0100 Received: from lara.cc.fer.hr ([161.53.72.113]) by main.gmane.org with esmtp (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 28 Feb 2013 18:02:22 +0100 Received: from ivoras by lara.cc.fer.hr with local (Gmexim 0.1 (Debian)) id 1AlnuQ-0007hv-00 for ; Thu, 28 Feb 2013 18:02:22 +0100 X-Injected-Via-Gmane: http://gmane.org/ To: freebsd-geom@freebsd.org From: Ivan Voras Subject: Re: Unexpected SU+J inconsistency AGAIN -- please, don't shift topic to ZFS! Date: Thu, 28 Feb 2013 18:01:46 +0100 Lines: 54 Message-ID: References: <1796551389.20130228120630@serebryakov.spb.ru> <1238720635.20130228123325@serebryakov.spb.ru> <1158712592.20130228141323@serebryakov.spb.ru> <583012022.20130228143129@serebryakov.spb.ru> <1502041051.20130228185647@serebryakov.spb.ru> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="------------enig12065FB88A964A3B91C9C4FD" X-Complaints-To: usenet@ger.gmane.org X-Gmane-NNTP-Posting-Host: lara.cc.fer.hr User-Agent: Mozilla/5.0 (X11; FreeBSD amd64; rv:14.0) Gecko/20120812 Thunderbird/14.0 In-Reply-To: <1502041051.20130228185647@serebryakov.spb.ru> X-Enigmail-Version: 1.4.3 Cc: freebsd-fs@freebsd.org X-BeenThere: freebsd-geom@freebsd.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: GEOM-specific discussions and implementations List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 28 Feb 2013 17:02:09 -0000 This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig12065FB88A964A3B91C9C4FD Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 28/02/2013 15:56, Lev Serebryakov wrote: > One time, Kirk say, that delayed writes are Ok for SU until bottom > layer doesn't lie about operation completeness. geom_raid5 could > delay writes (in hope that next writes will combine nicely and allow > not to do read-calculate-write cycle for read alone), but it never > mark BIO complete until it is really completed (layers down to > geom_raid5 returns completion). So, every BIO in wait queue is "in > flight" from GEOM/VFS point of view. Maybe, it is fatal for journal :(= It shouldn't be - it could be a bug. > And want I really want to see is "SYNC" flag for BIO and that all > journal-related writes will be marked with it. Also all commits > originated with fsync() MUST be marked in same way, really. Alexander > Motin (ahci driver author) assured me, that he'll add support for > such flag in driver to flush drive cache too, if it will be > introduced. Hmmm, once upon a time I actually tried to add it: http://people.freebsd.org/~ivoras/diffs/fsync_flush.patch This is from 2011, and was never really reviewed. Kirk said it was a good idea (meaning the implementation could be wrong, YMMV) :) I don't know whether it's significant, but ffs_softdep.c contains 6 bawrite() calls (meaning buf async write), in softdep_process_journal(), softdep_journal_freeblocks(), softdep_fsync_mountdev(), sync_cgs(), and flush_deplist(). --------------enig12065FB88A964A3B91C9C4FD Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.19 (FreeBSD) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAlEvjXoACgkQ/QjVBj3/HSzgXQCZASkd1JTlv/mRSlZ8EdNtqVwp XNUAoI6V2WCe4D9mfizE/RTDA1g0SKrL =eK7Y -----END PGP SIGNATURE----- --------------enig12065FB88A964A3B91C9C4FD--