code: @Override
  	public void run() {
  		long now = System.currentTimeMillis();
  		final long stamp = lock.readLock();
  		try {
  			for (MemoryPartition partition : partitions.values()) {
  				partition.removeOldEntries(now);
  			}
  		} finally {
  			lock.unlockRead(stamp);
  		}
  	}
docs: --- REMOVE OLD ENTRIES ---