Re: Buffer Management

Tom Lane wrote:
> Curt Sampson <cjs@cynic.net> writes:
> > Note that your proposal of using mmap to replace sysv shared memory
> > relies on the behaviour I've described too.
> 
> True, but I was not envisioning mapping an actual file --- at least
> on HPUX, the only way to generate an arbitrary-sized shared memory
> region is to use MAP_ANONYMOUS and not have the mmap'd area connected
> to any file at all.  It's not farfetched to think that this aspect
> of mmap might work differently from mapping pieces of actual files.
> 
> In practice of course we'd have to restrict use of any such
> implementation to platforms where mmap behaves reasonably ... according
> to our definition of "reasonably".

Yes, I am told mapping /dev/zero is the same as the anon map.

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