On Sun, Mar 6, 2016 at 9:59 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: > Perhaps it was intentional when written, but if Robert's advice is correct > that the new upper-planner path nodes should copy up parallel_degree from > their children, then it cannot be the case that parallel_degree>0 in a > node above the scan level implies that that node type has any special > behavior for parallelism. > > I continue to bemoan the lack of documentation about what these fields > mean. As far as I can find, the sum total of the documentation about > this field is > > int parallel_degree; /* desired parallel degree; 0 = not parallel > */
While it doesn't particularly relate to parallel joins, I've expressed a general concern about the max_parallel_degree GUC that I think is worth considering again: http://www.postgresql.org/message-id/cam3swzrs1mtvrkkasy1xbshgzxkd6-hnxx3gq7x-p-dz0zt...@mail.gmail.com In summary, I think it's surprising that a max_parallel_degree of 1 doesn't disable parallel workers entirely. -- Peter Geoghegan -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
