Function ExecEagerFreeAgg

src/backend/executor/nodeAgg.c:5141–5205

}

static void
ExecEagerFreeAgg(AggState *node)
{
	int			transno;
	int         numGroupingSets = Max(node->maxsets, 1);
	int			setno;

	/*
	 * When ending a parallel worker, copy the statistics gathered by the
	 * worker back into shared memory so that it can be picked up by the main
	 * process to report in EXPLAIN ANALYZE.
	 */
	if (node->shared_info && IsParallelWorker())
	{
		AggregateInstrumentation *si;

		Assert(ParallelWorkerNumber <= node->shared_info->num_workers);
		si = &node->shared_info->sinstrument[ParallelWorkerNumber];
		si->hash_batches_used = node->hash_batches_used;
		si->hash_disk_used = node->hash_disk_used;
		si->hash_mem_peak = node->hash_mem_peak;
	}

	/* Make sure we have closed any open tuplesorts */
	if (node->sort_in)
	{
		tuplesort_end(node->sort_in);
		node->sort_in = NULL;
	}
	if (node->sort_out)
	{
		tuplesort_end(node->sort_out);
		node->sort_out = NULL;
	}

	hashagg_reset_spill_state(node);

	if (node->hash_metacxt != NULL)
	{
		MemoryContextDelete(node->hash_metacxt);
		node->hash_metacxt = NULL;
	}

	for (transno = 0; transno < node->numtrans; transno++)
	{
		if (!bms_is_member(transno, node->aggs_used))
			continue;
		for (setno = 0; setno < numGroupingSets; setno++)
		{
			AggStatePerTrans pertrans = &node->pertrans[transno];

			if (pertrans->sortstates[setno])
			{
				tuplesort_end(pertrans->sortstates[setno]);
				pertrans->sortstates[setno] = NULL;
			}
		}
	}