@Override
        public void run() {
            if (ClusterManager.isClusteringStarted() && !ClusterManager.isSeniorClusterMember()) {
                // Do nothing if we are in a cluster and this JVM is not the senior cluster member
                return;
            }
            try {
                Date cleanUpDate = getCleanupDate();
                if (cleanUpDate!=null)
                {
                    totalChatTime += localMUCRoomManager.unloadInactiveRooms(cleanUpDate).toMillis();
                }
            }
            catch (final Throwable e) {
                Log.error(LocaleUtils.getLocalizedString("admin.error"), e);
            }
        }
Removes from memory rooms that have been without activity for a period of time. A room is
considered without activity when no occupants are present in the room for a while.
xmppserver/src/main/java/org/jivesoftware/openfire/muc/spi/MultiUserChatServiceImpl.java