Thanks for your inputs. After setting force_parallel_mode=off Execution time of same query was reduced to 1ms from 200 ms. Worked like a charm. We also increased work_mem to 80=MB. Thanks again.
On Sat, Apr 03, 2021 at 11:39:19AM -0400, Tom Lane wrote: > Bruce Momjian <bruce@momjian.us> writes: > > On Sat, Apr 3, 2021 at 08:38:18PM +0530, aditya desai wrote: > >> Yes, force_parallel_mode is on. Should we set it off? > > > Yes. I bet someone set it without reading our docs: > > > https://www.postgresql.org/docs/13/runtime-config-query.html#RUNTIME-CONFIG-QUERY-OTHER > > > --> Allows the use of parallel queries for testing purposes even in cases > > --> where no performance benefit is expected. > > > We might need to clarify this sentence to be clearer it is _only_ for > > testing. > > I wonder why it is listed under planner options at all, and not under > developer options.
Because it's there to help DBAs catch errors in functions incorrectly marked as parallel safe.
