code: public void runInvalidation() {
          ((BackedHashMap) _sessions).cleanUpCache(System.currentTimeMillis());
          if(!FrameworkState.isStopping()) {
              ((BackedHashMap) _sessions).performInvalidation();
          } else {
              if (com.ibm.websphere.ras.TraceComponent.isAnyTracingEnabled() && LoggingUtil.SESSION_LOGGER_WAS.isLoggable(Level.FINE)) {
                  LoggingUtil.SESSION_LOGGER_WAS.logp(Level.FINE, methodClassName, "runInvalidation", "Skipping background session invalidation because server is shutting down.");
              }
          }
          /*
           * if (_isApplicationSessionStore) {
           * ((BackedHashMap)_sessions).performAppSessionInvalidation();
           * } else {
           * ((BackedHashMap)_sessions).performInvalidation();
           * }
           */
      }
docs: /*
  runInvalidation - perform background invalidation of timed out sessions