Re: asynchronous execution

Thank you for looking this.

At Wed, 28 Jun 2017 10:23:54 +0200, Antonin Houska <ah(at)cybertec(dot)at> wrote in <4579(dot)1498638234(at)localhost>
> Kyotaro HORIGUCHI <horiguchi(dot)kyotaro(at)lab(dot)ntt(dot)co(dot)jp> wrote:
>
> > The patch got conflicted. This is a new version just rebased to
> > the current master. Furtuer amendment will be taken later.
>
> Can you please explain this part of make_append() ?
>
> /* Currently async on partitioned tables is not available */
> Assert(nasyncplans == 0 || partitioned_rels == NIL);
>
> I don't think the output of Append plan is supposed to be ordered even if the
> underlying relation is partitioned. Besides ordering, is there any other
> reason not to use the asynchronous execution?

It was just a developmental sentinel that will remind me later to
consider the declarative partitions since I didn't have an idea
of the differences (or the similarity) between appendrels and
partitioned_rels. It is never to say the condition cannot
make. I'll check it out and will support partitioned_rels sooner.
Sorry for having left it as it is.

> And even if there was some, the planner should ensure that executor does not
> fire the assertion statement above. The script attached shows an example how
> to cause the assertion failure.

regards,

--
Kyotaro Horiguchi
NTT Open Source Software Center