From: Cyril Hrubis <chrubis@suse.cz>
To: Andrea Cervesato <andrea.cervesato@suse.de>
Cc: Linux Test Project <ltp@lists.linux.it>
Subject: Re: [LTP] [PATCH v2] io: fix really slow dio_sparse on certain systems
Date: Mon, 26 Jan 2026 12:44:32 +0100 [thread overview]
Message-ID: <aXdToM9WIDy-39Ng@yuki.lan> (raw)
In-Reply-To: <aXdTEreda0-s6WID@yuki.lan>
Hi!
> I guess it's not about slow buffering. What I suppose happens is that
> every time the writer thread writes with O_DIRECT it invalidates the
> page cache and we have to re-read everything from disk. Which measn that
> the data are often removed from the cache between the reads and the
> reader processes are often forced to re-read the data from the disk. If
> there was no O_DIRECT reader thread the first child that happens to read
^
writer
--
Cyril Hrubis
chrubis@suse.cz
--
Mailing list info: https://lists.linux.it/listinfo/ltp
next prev parent reply other threads:[~2026-01-26 11:43 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-01-26 8:41 [LTP] [PATCH v2] io: fix really slow dio_sparse on certain systems Andrea Cervesato
2026-01-26 11:16 ` Petr Vorel
2026-01-26 11:42 ` Cyril Hrubis
2026-01-26 11:44 ` Cyril Hrubis [this message]
2026-01-26 15:07 ` Andrea Cervesato via ltp
2026-01-26 15:47 ` Cyril Hrubis
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