From: Giuliano Pochini <pochini@shiny.it>
To: Robert Love <rml@tech9.net>
Cc: linux-kernel@vger.kernel.org, Mark Mielke <mark@mark.mielke.cc>,
Jamie Lokier <lk@tantalophile.demon.co.uk>,
andersen@codepoet.org
Subject: Re: [PATCH] O_STREAMING - flag for optimal streaming I/O
Date: Thu, 10 Oct 2002 15:39:19 +0200 (CEST) [thread overview]
Message-ID: <XFMail.20021010153919.pochini@shiny.it> (raw)
In-Reply-To: <1034221067.794.505.camel@phantasy>
> Look, the pagecache is already smart. New stuff will replace unusued
> old stuff. On VM pressure, the pagecache will be pruned. Streaming I/O
> is a fundamentally different problem in that the data is so large it
> _continually_ thrashes the pagecache. Such I/O is sequential and
> use-once. You end up with a permanent waste of memory (the cached
> I/O).
When a process opens a file with O_STREAMING, it tells the kernel
it will use the data only once, but it tells nothing about other
tasks. If that process reads something which is already cached,
then it must not drop it because someone other used it recently
and IMHO pagecache only should be allowed to drop it.
> Let's prove we have a solution to this problem before going after
> tangent ones.
If "solution" means "code", sorry, I can't help :(
Bye.
next prev parent reply other threads:[~2002-10-10 13:33 UTC|newest]
Thread overview: 68+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-10-08 2:38 Robert Love
2002-10-08 10:42 ` J.A. Magallon
2002-10-08 18:08 ` Robert Love
2002-10-08 18:38 ` Chris Wedgwood
2002-10-08 18:49 ` Robert Love
2002-10-08 19:05 ` Chris Wedgwood
2002-10-08 19:17 ` Robert Love
2002-10-08 19:30 ` Andrew Morton
2002-10-09 14:14 ` Marco Colombo
2002-10-09 16:30 ` kernel
2002-10-08 19:52 ` Chris Wedgwood
2002-10-08 19:59 ` Robert Love
2002-10-08 20:01 ` Chris Wedgwood
2002-10-09 8:33 ` Giuliano Pochini
2002-10-09 8:43 ` Andrew Morton
2002-10-09 10:55 ` Giuliano Pochini
2002-10-09 17:05 ` Mark Mielke
2002-10-09 19:36 ` Giuliano Pochini
2002-10-09 22:24 ` Mark Mielke
2002-10-09 23:20 ` Jamie Lokier
2002-10-10 3:07 ` Mark Mielke
2002-10-10 10:55 ` Helge Hafting
2002-10-10 17:50 ` Mark Mielke
2002-10-10 3:29 ` Erik Andersen
2002-10-10 3:37 ` Robert Love
2002-10-10 13:39 ` Giuliano Pochini [this message]
2002-10-10 22:50 ` Mike Fedyk
2002-10-10 22:58 ` Erik Andersen
2002-10-11 8:26 ` Giuliano Pochini
2002-10-11 8:32 ` Helge Hafting
2002-10-10 8:33 ` Giuliano Pochini
2002-10-10 9:10 ` Erik Andersen
2002-10-10 9:38 ` Giuliano Pochini
2002-10-10 10:40 ` Miquel van Smoorenburg
2002-10-10 11:01 ` Helge Hafting
2002-10-10 12:29 ` Xavier Bestel
2002-10-10 13:17 ` Giuliano Pochini
2002-10-10 22:44 ` Mike Fedyk
2002-10-11 8:13 ` Giuliano Pochini
2002-10-10 11:38 ` O_STREAMING has insufficient info - how about fadvise() ? Alan Cox
2002-10-10 11:47 ` William Lee Irwin III
2002-10-10 15:34 ` Andrew Morton
2002-10-10 16:08 ` Alan Cox
2002-10-10 16:49 ` Oliver Xymoron
2002-10-10 15:37 ` [PATCH] O_STREAMING - flag for optimal streaming I/O Gerhard Mack
2002-10-10 22:47 ` Mike Fedyk
2002-10-11 2:14 ` Gerhard Mack
2002-10-11 8:10 ` Chris Wedgwood
2002-10-10 9:14 ` David Lang
2002-10-10 14:51 ` Denis Vlasenko
2002-10-08 19:53 ` Matthias Schniedermeyer
2002-10-08 19:59 ` Chris Wedgwood
2002-10-08 20:03 ` Andrew Morton
2002-10-08 20:34 ` Matthias Schniedermeyer
2002-10-08 20:42 ` Andrew Morton
2002-10-08 20:37 ` Larry McVoy
2002-10-09 11:53 ` Roy Sigurd Karlsbakk
2002-10-09 14:10 ` Marco Colombo
2002-10-09 14:14 ` Robert Love
2002-10-09 14:33 ` Richard B. Johnson
2002-10-09 15:27 ` Andreas Dilger
2002-10-09 23:17 ` Jamie Lokier
2002-10-09 23:46 ` Rik van Riel
2002-10-10 0:16 ` Jamie Lokier
2002-10-10 2:39 ` Erik Andersen
2002-10-10 10:33 ` Marco Colombo
2002-10-10 20:00 ` Erik Andersen
2002-10-11 4:16 Hank Leininger
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