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Subject: Re: madvise() vs posix_fadvise()
From: Dmitry Sivachenko <trtrmitya@gmail.com>
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Date: Thu, 3 Apr 2014 23:10:49 +0400
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To: John Baldwin <jhb@FreeBSD.org>
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On 03 =C1=D0=D2. 2014 =C7., at 20:30, John Baldwin <jhb@FreeBSD.org> =
wrote:

>=20
> The latter.  It's sort of like a lazy O_DIRECT.  Each time you call =
write(2),
> it tries to move any clean pages from your current sequentially =
written
> stream from inactive to cache, so the pages won't move until a =
subsequent
> write(2) after bufdaemon or the syncer actually forces them to be =
written.
> Unfortunately, it is currently implemented by doing an internal
> FADV_DONTNEED after each read() or write().  It would be better if it =
was
> implemented as a callback when buffers are completed.



Sounds like FADV_NOREUSE should be befeficial for any log-writing =
program? (syslogd, apache, nginx, .....)=