private void stopProcedureExecutor() {
    if (procedureExecutor != null) {
      configurationManager.deregisterObserver(procedureExecutor.getEnvironment());
      procedureExecutor.getEnvironment().getRemoteDispatcher().stop();
      procedureExecutor.stop();
      procedureExecutor.join();
      procedureExecutor = null;
    }

    if (procedureStore != null) {
      procedureStore.stop(isAborted());
      procedureStore = null;
    }
  }
Turn on/off Snapshot Cleanup Chore
@param on indicates whether Snapshot Cleanup Chore is to be run
hbase-server/src/main/java/org/apache/hadoop/hbase/master/HMaster.java