docs: public static MemorySize getJobManagerHeapMemory(Configuration configuration) {
  		if (configuration.containsKey(JobManagerOptions.JOB_MANAGER_HEAP_MEMORY.key())) {
  			return MemorySize.parse(configuration.getString(JobManagerOptions.JOB_MANAGER_HEAP_MEMORY));
  		} else if (configuration.containsKey(JobManagerOptions.JOB_MANAGER_HEAP_MEMORY_MB.key())) {
  			return MemorySize.parse(configuration.getInteger(JobManagerOptions.JOB_MANAGER_HEAP_MEMORY_MB) + "m");
  		} else {
  			//use default value
  			return MemorySize.parse(configuration.getString(JobManagerOptions.JOB_MANAGER_HEAP_MEMORY));
  		}
  	}