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Date: Fri, 05 Sep 2003 01:26:10 -0700
From: Terry Lambert <tlambert2@mindspring.com>
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To: Sean Chittenden <sean@chittenden.org>
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Subject: Re: Best disk caching method (and PGSQL performance)
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Sean Chittenden wrote:
> > Also, has anyone played with the other fsync options?
> 
> FreeBSD only supports the default fsync option.

And as the comments point out, it lacks the introspection to
know dirty pages from clean ones, so all pages that are in
core and associated with the object are written, not just
the dirty ones.  Avoid this, if possible.

It would be nice if there were an fcntl that would F_SYNCRANGE
or something similar, so the applicaion could hint the range it
wanted written to the kernel.

-- Terry