Re: subscription/015_stream sometimes breaks

On 2023-Aug-23, Zhijie Hou (Fujitsu) wrote:

> [1]--
> 		LWLockAcquire(LogicalRepWorkerLock, LW_SHARED);
> 
> 		workers = logicalrep_workers_find(MyLogicalRepWorker->subid, true);
> 		foreach(lc, workers)
> 		{
> 			LogicalRepWorker *w = (LogicalRepWorker *) lfirst(lc);
> 
> **			if (isParallelApplyWorker(w))
> 				logicalrep_worker_stop_internal(w, SIGTERM);
> 		}

Hmm, I think if worker->in_use is false, we shouldn't consult the rest
of the struct at all, so I propose to add the attached 0001 as a minimal
fix.

In fact, I'd go further and propose that if we do take that stance, then
we don't need clear out the contents of this struct at all, so let's
not.  That's 0002.

And the reason 0002 does not remove the zeroing of ->proc is that the
tests gets stuck when I do that, and the reason for that looks to be
some shoddy coding in WaitForReplicationWorkerAttach, so I propose we
change that too, as in 0003.

Thoughts?

-- 
Álvaro Herrera         PostgreSQL Developer  —  https://www.EnterpriseDB.com/