Re: how does PostgreSQL determine how many parallel processes to start

2021-02-19 Thread Laurenz Albe
On Fri, 2021-02-19 at 11:21 +0100, Luca Ferrari wrote: > > At execution time, PostgreSQL will use as many of the planned workers > > as are currently available (max_parallel_workers). > > Thanks, but just to make it clear, assuming I execute almost > simultanously two identical queries that can be

Re: how does PostgreSQL determine how many parallel processes to start

2021-02-19 Thread Luca Ferrari
On Fri, Feb 19, 2021 at 10:43 AM Laurenz Albe wrote: > At execution time, PostgreSQL will use as many of the planned workers > as are currently available (max_parallel_workers). Thanks, but just to make it clear, assuming I execute almost simultanously two identical queries that can be therefore

Re: how does PostgreSQL determine how many parallel processes to start

2021-02-19 Thread Laurenz Albe
On Fri, 2021-02-19 at 10:38 +0100, Luca Ferrari wrote: > I know that parallel processes can be limited by > max_parallel_workers_per_gather and max_parallel_workers, as well as > the condition to consider a parallel plan is min_table_scan_size (and > index). But I would like to understand, once a t