That explains a lot.
I have the default of 2 max_parallel_maintenance_workers set, should I set this to 0?
I realize this is of course an improvement, but working with docker containers, I'd like to avoid taking /dev/shm away from regular queries.
I assume setting max_parallel_maintenance_workers to 0 is the fix here, is there perhaps something else I should know about, if I want to have control over this?
Regards,
Koen De Groote
On Wed, Nov 20, 2024 at 12:38 AM Thomas Munro <thomas.munro@xxxxxxxxx> wrote:
On Wed, Nov 20, 2024 at 11:22 AM Koen De Groote <kdg.dev@xxxxxxxxx> wrote:
> Why would that be? It's the exact same data. The install is about 50GB in size. Is there something wrong with postgres 16, or did some settings significantly change, that I need to know about? I went over all the changelogs, nothing stood out as relevant to this, but that might be a lack of experience on my end.
Parallel vacuum arrived in PostgreSQL 13, and that uses "dynamic
shared memory" to share state between workers, and assuming
dynamic_shared_memory_type=posix, that means shm_open(), which opens
files under /dev/shm on Linux.
