Re: Parallel Append implementation

On Thu, Mar 16, 2017 at 8:48 AM, Ashutosh Bapat
<ashutosh(dot)bapat(at)enterprisedb(dot)com> wrote:
> Why do we need following code in both ExecAppendInitializeWorker() and
> ExecAppendInitializeDSM()? Both of those things happen before starting the
> actual execution, so one of those should suffice?
> + /* Choose the optimal subplan to be executed. */
> + (void) parallel_append_next(node);

ExecAppendInitializeWorker runs only in workers, but
ExecAppendInitializeDSM runs only in the leader.

> BTW, sa_finished seems to be a misnomor. The plan is not finished yet, but it
> wants no more workers. So, should it be renamed as sa_no_new_workers or
> something like that?

I think that's not going to improve clarity. The comments can clarify
the exact semantics.

--
Robert Haas
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