Hi, On Thu, Mar 12, 2026 at 07:59:43PM +0100, Tomas Vondra wrote: > Hi, > > While hacking on something I happened to notice a couple asserts on > ParallelWorkerNumber when collecting shared instrumentation: > > Assert(ParallelWorkerNumber <= node->shared_info->num_workers); > > This is not quire right, because num_workers is used to size arrays > indexed by ParallelWorkerNumber. And the comment in parallel.c also > claims (ParallelWorkerNumber < num_workers). > > So AFAICS the assert(s) should be > > Assert(ParallelWorkerNumber < node->shared_info->num_workers);
I think that you're right. It looks like the first one has been introduced by bf11e7ee2e3 and then the others are probably copy/paste. > I don't think we had issues with this not catching a bug. But it may be > a bit misleading, so worth fixing and (probably) backpatching. I do agree. With that patch applied, the remaining one: $ git grep "<=.*num_workers" src/backend/executor/nodeGatherMerge.c: Assert(nreaders <= castNode(GatherMerge, gm_state->ps.plan)->num_workers); does not need to be fixed, so I think that your patch does not miss any and LGTM. Regards, -- Bertrand Drouvot PostgreSQL Contributors Team RDS Open Source Databases Amazon Web Services: https://aws.amazon.com
