Re: pg_shmem_allocations view

On 2014-05-06 22:04:04 +0100, Simon Riggs wrote:
> On 6 May 2014 20:44, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> > Robert Haas <robertmhaas(at)gmail(dot)com> writes:
> >> On Tue, May 6, 2014 at 2:34 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> >>> FWIW, I vote for fixing (a) now but holding (b) for 9.5.
> >
> >> I guess I'll vote for applying both. I don't see a lot of risk, and I
> >> think doing one with out the other is somewhat pointless.
> >
> > The difference is that there's not consensus about the details of the
> > views ... as borne out by your next paragraph.
> >
> > Now admittedly, we could always redefine the views in 9.5, but
> > I'd rather not be doing this sort of thing in haste. Something
> > as user-visible as a system view really ought to have baked awhile
> > before we ship it. Patch (a) is merely institutionalizing the
> > expectation that DSM segments should have names, which is a much
> > lower-risk bet.
>
> As long as all the functions are exposed to allow b) to run as an
> extension, I don't see we lose anything by waiting a while.

They aren't exposed. It's touching implementation details in both
shmem.c and dsm.c. I think that's actually fine.
Imo it's not too bad if we don't get either in 9.4. It's not a critical
feature.What I *would* like to avoid is a pointless API break between
9.4 and 9.5. Because I will push for the patch in 9.5 CF1...

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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