private void startLocalCluster() { synchronized (lock) { if (localCluster == null) { org.apache.flink.configuration.Configuration configuration = new org.apache.flink.configuration.Configuration(); configuration.setInteger( ConfigConstants.TASK_MANAGER_NUM_TASK_SLOTS, env.getParallelism() * 2); localCluster = new LocalFlinkMiniCluster(configuration, false); localCluster.start(); } localClusterUsers++; } }