Hello, On Sun, Oct 13, 2024 at 08:16:04AM +1300, Thomas Munro wrote: > > template1=> SELECT COUNT(*) FROM pg_class a, pg_class b, pg_class c; > > > > I see only one 100% CPU PostgreSQL process. > > If you set set min_parallel_table_scan_size = 0 then it uses Without it, it uses one CPU and takes about 8.5 s (count is 57512456). With it, it is indeed parallel (multiple CPU used) and it takes about 6s. As this is on a machine with slow disks, it is perfectly ok, I just wanted to see the CPU parallelism in action. Thank you!
