/**
 * This copies out the current state of resource queues.
 */
static void
BuildQueueStatusContext(QueueStatusContext *fctx)
{
……
	/* Initialize for a sequential scan of the resource queue hash. */
	hash_seq_init(&status, ResQueueHash);
	num_calls = hash_get_num_entries(ResQueueHash);
	Assert(num_calls == ResScheduler->num_queues);