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Date: Mon, 14 Apr 2003 22:30:52 -0700
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Jamie Lokier <jamie@shareable.org>
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Subject: Re: Memory mapped files question
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Jamie Lokier wrote:
> 
> It's a quality of implementation issue if data can remain dirty in RAM
> forever without ever being flushed.
> 
> Can this really happen with normal open/mmap/munmap/close usage, or
> does it only occur with long-lived processes like innd which mmap a
> file, dirty the pages but never munmap them?
> 
> If the former case does happen, I'd say we're failing on quality of
> implementation.  If it's only the latter case, though, fair enough: the
> application writer will have to use msync().
> 

The latter, I'm pretty sure.  After all, that's what pgflush/bdflush is 
all about.