Re: Experimental dynamic memory allocation of postgresql shared memory

On 18 June 2016 at 02:42, Robert Haas <robertmhaas(at)gmail(dot)com> wrote:

> On Fri, Jun 17, 2016 at 2:23 PM, Aleksey Demakov <ademakov(at)gmail(dot)com>
> wrote:
> > Essentially this is pessimizing for the lowest common denominator
> > among OSes.
>
> I totally agree. That's how we make the server portable.
>
> > Having a contiguous address space makes things so
> > much simpler that considering this case, IMHO, is well worth of it.
>
> I think that would be great if you could make it work, but it has to
> support Linux, Windows (all supported versions), MacOS X, all the
> various BSD flavors for which we have buildfarm animals, and other
> platforms that we currently run on like HP-UX. If you come up with a
> solution that works for this on all of those platforms, I will shake
> your hand. But I think that's probably impossible, or at least
> really, really hard.
>

Indeed. In particular, ASLR on Windows or anywhere we EXEC_BACKEND will
cause difficuties attaching to those segments.

--
Craig Ringer http://www.2ndQuadrant.com/
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