@Override
    public MemoryComputeKey<MutableMetrics> getMemoryComputeKey() {
        return MemoryComputeKey.of(this.getId(), ProfileBiOperator.instance(), false, true);
    }
Returns {@code Optional.empty()} if traversal is not iterated or if not locked after strategy application.
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/process/traversal/step/util/ProfileStep.java