@Setup(Level.Trial)
    public void setup() {
        // Ensure there are enough racks and brokers for the replication factor = 3.
        if (NUMBER_OF_RACKS < 3) {
            throw new IllegalArgumentException("Number of broker racks must be at least equal to 3.");
        }

        populateTopicMetadata();

        addMemberSubscriptions();

        assignor = assignorType.assignor();

        if (assignmentType == AssignmentType.INCREMENTAL) {
            simulateIncrementalRebalance();
        }
    }
The assignment type is decided based on whether all the members are assigned partitions
for the first time (full), or incrementally when a rebalance is triggered.
jmh-benchmarks/src/main/java/org/apache/kafka/jmh/assignor/ClientSideAssignorBenchmark.java