Re: create index insist on 2 workers only

On Fri, Apr 24, 2020 at 7:32 AM Radoslav Nedyalkov <rnedyalkov(at)gmail(dot)com> wrote:
> We 're rebuilding a big table which has set parallel_workers = 6
> system has
> max_parallel_maintenance_workers | 6 | /var/lib/pgsql/11/data/postgresql.sumup.conf
> max_parallel_workers | 16 | /var/lib/pgsql/11/data/postgresql.sumup.conf
> max_parallel_workers_per_gather | 4 | /var/lib/pgsql/11/data/postgresql.sumup.conf
>
> Also session level on index restore there is
> set max_parallel_maintenance_workers = 6;
>
> Still we get only 2 parallel processes in a free of any other load system.
> It is postgres 11.7

Try increasing maintenance_work_mem from the default of 64MB. MWM
constrains the number of parallel workers used.

--
Peter Geoghegan