From: Alan Cox <alan-qBU/x9rampVanCEyBjwyrvXRex20P6io@public.gmane.org>
To: Howard Chu <hyc-aQkYFu9vm6AAvxtiuMwx3w@public.gmane.org>
Cc: General Discussion of SQLite Database
<sqlite-users-CzDROfG0BjIdnm+yROfE0A@public.gmane.org>,
Theodore Ts'o <tytso-3s7WtUTddSA@public.gmane.org>,
drh-X1OJI8nnyKUAvxtiuMwx3w@public.gmane.org,
linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org,
Vladislav Bolkhovitin <vst-d+Crzxg7Rs0@public.gmane.org>
Subject: Re: light weight write barriers
Date: Fri, 2 Nov 2012 12:33:59 +0000 [thread overview]
Message-ID: <20121102123359.2479a7dc@pyramind.ukuu.org.uk> (raw)
In-Reply-To: <50931601.4060102-aQkYFu9vm6AAvxtiuMwx3w@public.gmane.org>
> Isn't any type of kernel-side ordering an exercise in futility, since
> a) the kernel has no knowledge of the disk's actual geometry
> b) most drives will internally re-order requests anyway
They will but only as permitted by the commands queued, so you have some
control depending upon the interface capabilities.
> c) cheap drives won't support barriers
Barriers are pretty much universal as you need them for power off !
> Even assuming the drives honored all your requests without lying, how would
> you really want this behavior exposed? From the userland perspective, there
> are very few apps that care. Probably only transactional databases, really.
And file systems internally sometimes. A file system is after all a
transactional database of sorts.
Alan
next prev parent reply other threads:[~2012-11-02 12:33 UTC|newest]
Thread overview: 108+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <415E76CC-A53D-4643-88AB-3D7D7DC56F98@dubeyko.com>
2012-10-06 13:54 ` [PATCH 00/16] f2fs: introduce flash-friendly file system Vyacheslav Dubeyko
2012-10-06 20:06 ` Jaegeuk Kim
2012-10-07 7:09 ` Marco Stornelli
2012-10-07 9:31 ` Jaegeuk Kim
2012-10-07 12:08 ` Vyacheslav Dubeyko
2012-10-08 8:25 ` Jaegeuk Kim
2012-10-08 9:59 ` Namjae Jeon
2012-10-08 10:52 ` Jaegeuk Kim
2012-10-08 11:21 ` Namjae Jeon
2012-10-08 12:11 ` Jaegeuk Kim
2012-10-09 3:52 ` Namjae Jeon
2012-10-09 8:00 ` Jaegeuk Kim
2012-10-09 8:31 ` Lukáš Czerner
2012-10-09 10:45 ` Jaegeuk Kim
2012-10-09 11:01 ` Lukáš Czerner
2012-10-09 12:01 ` Jaegeuk Kim
2012-10-09 12:39 ` Lukáš Czerner
2012-10-09 13:10 ` Jaegeuk Kim
2012-10-09 21:20 ` Dave Chinner
2012-10-10 2:32 ` Jaegeuk Kim
2012-10-10 4:53 ` Theodore Ts'o
2012-10-12 20:55 ` Arnd Bergmann
2012-10-10 10:36 ` David Woodhouse
2012-10-12 20:58 ` Arnd Bergmann
2012-10-13 4:26 ` Namjae Jeon
2012-10-13 12:37 ` Jaegeuk Kim
2012-10-17 11:12 ` Namjae Jeon
[not found] ` <000001cdacef$b2f6eaa0$18e4bfe0$%kim@samsung.com>
2012-10-18 13:39 ` Vyacheslav Dubeyko
2012-10-18 22:14 ` Jaegeuk Kim
2012-10-19 9:20 ` NeilBrown
2012-10-08 19:22 ` Vyacheslav Dubeyko
2012-10-09 7:08 ` Jaegeuk Kim
2012-10-09 19:53 ` Jooyoung Hwang
2012-10-10 8:05 ` Vyacheslav Dubeyko
2012-10-10 9:02 ` Theodore Ts'o
2012-10-10 11:52 ` SQLite on flash (was: [PATCH 00/16] f2fs: introduce flash-friendly file system) Clemens Ladisch
[not found] ` <50756199.1090103-P6GI/4k7KOmELgA04lAiVw@public.gmane.org>
2012-10-10 12:47 ` Richard Hipp
2012-10-10 17:17 ` light weight write barriers Andi Kleen
[not found] ` <m2fw5mtffg.fsf_-_-Vw/NltI1exuRpAAqCnN02g@public.gmane.org>
2012-10-10 17:48 ` Richard Hipp
[not found] ` <CALwJ=MyR+nU3zqi3V3JMuEGNwd8FUsw9xLACJvd0HoBv3kRi0w-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2012-10-11 16:38 ` Nico Williams
[not found] ` <CAK3OfOi3E1ePfzWjq1epFaXsjtn8V_=r3h+PG6ankWW2fOr6GA-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2012-10-11 16:48 ` Nico Williams
2012-10-11 16:32 ` 杨苏立 Yang Su Li
2012-10-11 17:41 ` [sqlite] " Christoph Hellwig
2012-10-23 19:53 ` Vladislav Bolkhovitin
[not found] ` <5086F5A7.9090406-d+Crzxg7Rs0@public.gmane.org>
2012-10-24 21:17 ` Nico Williams
2012-10-24 22:03 ` [sqlite] " david
[not found] ` <alpine.DEB.2.02.1210241447210.8519-Z4YwzcCRHZnr5h6Zg1Auow@public.gmane.org>
2012-10-25 0:20 ` Nico Williams
2012-10-25 1:04 ` [sqlite] " david
[not found] ` <alpine.DEB.2.02.1210241748180.8519-Z4YwzcCRHZnr5h6Zg1Auow@public.gmane.org>
2012-10-25 5:18 ` Nico Williams
2012-10-25 6:02 ` [sqlite] " Theodore Ts'o
2012-10-25 6:58 ` david
[not found] ` <alpine.DEB.2.02.1210242331060.31862-Z4YwzcCRHZnr5h6Zg1Auow@public.gmane.org>
2012-10-25 14:03 ` Theodore Ts'o
[not found] ` <20121025140327.GB13562-AKGzg7BKzIDYtjvyW6yDsg@public.gmane.org>
2012-10-25 18:03 ` david-gFPdbfVZQbY
[not found] ` <alpine.DEB.2.02.1210251048280.8519-Z4YwzcCRHZnr5h6Zg1Auow@public.gmane.org>
2012-10-25 18:29 ` Theodore Ts'o
2012-11-05 20:03 ` [sqlite] " Pavel Machek
[not found] ` <20121105200348.GB15821-5NIqAleC692hcjWhqY66xCZi+YwRKgec@public.gmane.org>
2012-11-05 22:04 ` Theodore Ts'o
[not found] ` <20121105220440.GB25378-AKGzg7BKzIDYtjvyW6yDsg@public.gmane.org>
2012-11-05 22:37 ` Richard Hipp
[not found] ` <CALwJ=Mx-uEFLXK2wywekk=0dwrwVFb68wocnH9bjXJmHRsJx3w-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2012-11-05 23:00 ` Theodore Ts'o
2012-10-30 23:49 ` [sqlite] " Nico Williams
2012-10-25 5:42 ` Theodore Ts'o
2012-10-25 7:11 ` david
2012-10-27 1:52 ` Vladislav Bolkhovitin
2012-10-25 5:14 ` Theodore Ts'o
2012-10-25 13:03 ` Alan Cox
[not found] ` <20121025140325.49cd7c79-38n7/U1jhRXW96NNrWNlrekiAK3p4hvP@public.gmane.org>
2012-10-25 13:50 ` Theodore Ts'o
2012-10-27 1:55 ` [sqlite] " Vladislav Bolkhovitin
2012-10-27 1:54 ` Vladislav Bolkhovitin
[not found] ` <508B3EED.2080003-d+Crzxg7Rs0@public.gmane.org>
2012-10-27 4:44 ` Theodore Ts'o
2012-10-30 22:22 ` [sqlite] " Vladislav Bolkhovitin
[not found] ` <5090532D.4050902-d+Crzxg7Rs0@public.gmane.org>
2012-10-31 9:54 ` Alan Cox
2012-11-01 20:18 ` [sqlite] " Vladislav Bolkhovitin
[not found] ` <5092D90F.7020105-d+Crzxg7Rs0@public.gmane.org>
2012-11-01 21:24 ` Alan Cox
2012-11-02 0:15 ` [sqlite] " Vladislav Bolkhovitin
[not found] ` <20121101212418.140e3a82-38n7/U1jhRXW96NNrWNlrekiAK3p4hvP@public.gmane.org>
2012-11-02 0:38 ` Howard Chu
[not found] ` <50931601.4060102-aQkYFu9vm6AAvxtiuMwx3w@public.gmane.org>
2012-11-02 12:24 ` Richard Hipp
2012-11-13 3:41 ` [sqlite] " Vladislav Bolkhovitin
2012-11-02 12:33 ` Alan Cox [this message]
2012-11-13 3:41 ` Vladislav Bolkhovitin
[not found] ` <50A1C15E.2080605-d+Crzxg7Rs0@public.gmane.org>
2012-11-13 17:40 ` Alan Cox
[not found] ` <20121113174000.6457a68b-38n7/U1jhRXW96NNrWNlrekiAK3p4hvP@public.gmane.org>
2012-11-13 19:13 ` Nico Williams
2012-11-15 1:17 ` [sqlite] " Vladislav Bolkhovitin
[not found] ` <50A442AF.9020407-d+Crzxg7Rs0@public.gmane.org>
2012-11-15 12:07 ` David Lang
[not found] ` <alpine.DEB.2.02.1211150353080.32408-UEhY+ZBZOcqqLGM74eQ/YA@public.gmane.org>
2012-11-15 16:14 ` 杨苏立 Yang Su Li
2012-11-17 5:02 ` [sqlite] " Vladislav Bolkhovitin
2012-11-16 15:06 ` Howard Chu
2012-11-16 15:31 ` [sqlite] " Ric Wheeler
[not found] ` <50A65C68.6080001-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>
2012-11-16 15:54 ` Howard Chu
2012-11-16 18:03 ` [sqlite] " Ric Wheeler
[not found] ` <50A65681.8000204-aQkYFu9vm6AAvxtiuMwx3w@public.gmane.org>
2012-11-16 19:14 ` David Lang
2012-11-17 5:02 ` [sqlite] " Vladislav Bolkhovitin
2012-11-15 17:06 ` Ryan Johnson
2012-11-15 22:35 ` [sqlite] " Chris Friesen
2012-11-17 5:02 ` Vladislav Bolkhovitin
2012-11-20 1:23 ` Vladislav Bolkhovitin
2012-11-26 20:05 ` Nico Williams
[not found] ` <CAK3OfOjD4XBGfu3cnMwTvCfec0Lvg3zrO16+pXtiFF4UWpFjDw-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
2012-11-29 2:15 ` Vladislav Bolkhovitin
2012-11-15 1:16 ` [sqlite] " Vladislav Bolkhovitin
2012-11-13 3:37 ` Vladislav Bolkhovitin
2012-11-11 4:25 ` 杨苏立 Yang Su Li
2012-11-13 3:42 ` [sqlite] " Vladislav Bolkhovitin
2012-10-10 7:57 ` [PATCH 00/16] f2fs: introduce flash-friendly file system Vyacheslav Dubeyko
2012-10-10 9:43 ` Jaegeuk Kim
2012-10-11 3:14 ` Namjae Jeon
[not found] ` <CAN863PuyMkSZtZCvqX+kwei9v=rnbBYVYr3TqBXF_6uxwJe2_Q@mail.gmail.com>
2012-10-17 11:13 ` Namjae Jeon
2012-10-17 23:06 ` Changman Lee
2012-10-12 12:30 ` Vyacheslav Dubeyko
2012-10-12 14:25 ` Jaegeuk Kim
2012-10-07 10:15 ` Vyacheslav Dubeyko
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