@SuppressWarnings("unchecked")
  public void init(Context context) {
    this.store = (KeyValueStore<String, String>) context.getTaskContext().getStore("mystore");
  }
A simple performance test that just reads in messages and writes them to a state store as quickly as possible and periodically prints out throughput numbers
samza-test/src/main/java/org/apache/samza/test/integration/StatePerfTestTask.java