pgsql: Avoid unnecessary shm writes in Parallel Hash Join.

Avoid unnecessary shm writes in Parallel Hash Join. Currently, Parallel Hash Join cannot be used for full/right joins, so there is no point in setting the match flag. It turns out that the cache coherence traffic generated by those writes slows down large systems running many-core joins, so let's

pgsql: Avoid unnecessary shm writes in Parallel Hash Join.

Avoid unnecessary shm writes in Parallel Hash Join. Currently, Parallel Hash Join cannot be used for full/right joins, so there is no point in setting the match flag. It turns out that the cache coherence traffic generated by those writes slows down large systems running many-core joins, so let's

pgsql: Avoid unnecessary shm writes in Parallel Hash Join.

Avoid unnecessary shm writes in Parallel Hash Join. Currently, Parallel Hash Join cannot be used for full/right joins, so there is no point in setting the match flag. It turns out that the cache coherence traffic generated by those writes slows down large systems running many-core joins, so let's