> Could you provide SQL dump and settings to play with this case locally?
>Also, I usually force parallel workers with settings like below:
>max_parallel_workers_per_gather = 32
>min_parallel_table_scan_size = 0
>min_parallel_index_scan_size = 0
>max_worker_processes = 64
>parallel_setup_cost = 0.001
>parallel_tuple_cost = 0.0001
I tried these configuration parameters and got the same worse query plan--- the HashJoin in fifth line is still not in parallel and the following HashJoin are in parallel.
However, this is an inefficient query plan.
I changed the code to generate an efficient query plan (only the HashJoin in fifth line is in parallel), so I am wondering whether it is possible to optimize the code to enable this efficient query plan in default? I believe at least, it would improve the performance of PostgreSQL on the standard benchmark TPC-H.
If you need, I can provide my environment in docker for your analysis.
Best regards,
Jinsheng Ba
Notice: This email is generated from the account of an NUS alumnus. Contents, views, and opinions therein are solely those of the sender.
