code: public void flushContainerPages(boolean online) {
  
          try {
              m_lock.writeLock().lock();
              if (online) {
                  m_containerPagesOnline.clear();
              } else {
                  m_containerPagesOffline.clear();
              }
          } finally {
              m_lock.writeLock().unlock();
          }
      }
docs: Flushes the container pages cache.<p>
  
  @param online if to flush the online or offline cache