On Mon, 2003-11-03 at 10:01, Tom Lane wrote:
> Neil Conway <neilc(at)samurai(dot)com> writes:
> > POSIX_FADV_RANDOM doesn't effect the page cache, it just determines how
> > aggressive the kernel is when doing readahead (at least on Linux, but
> > I'd expect to see other kernels implement similar behavior).
> I would expect POSIX_FADV_SEQUENTIAL to reduce the chance that a page
> will be kept in buffer cache after it's been used.
I don't think that can be reasonably implied from the POSIX text, which
Specifies that the application expects to access the specified
data sequentially from lower offsets to higher offsets.
The present Linux implementation doesn't do this, AFAICS -- all it does
it increase the readahead for this file:
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