On 2018-01-12 07:51:34 -0500, Robert Haas wrote:
> On Thu, Jan 11, 2018 at 11:01 PM, Thomas Munro
> <thomas.munro@enterprisedb.com> wrote:
> > Are you saying we should do the work now to create a per-transaction
> > DSM segment + DSA area + thing that every backend attaches to?
>
> No, I was just thinking you could stuff it into the per-parallel-query
> DSM/DSA. But...
>
> > I didn't think creating backend local hash tables would be a problem
> > because it's a vanishingly rare occurrence for the hash table to be
> > created at all (ie when you've altered an enum), and if created, to
> > have more than a couple of entries in it.
>
> ...this is also a fair point.
OTOH, it seems quite likely that we'll add more transaction-lifetime
shared data (e.g. combocid), so building per-xact infrastructure
actually seems like a good idea.
Greetings,
Andres Freund