public HashMap<MessageGid, LogRecord> constructComputationSet()
	{
		HashMap<MessageGid, LogRecord> comp = new HashMap<>();

        LogRecord log_record = null;
        UpdateMessage update_msg = null;
        MultipartTimestamp prev = null;

        for(Map.Entry<MessageGid, LogRecord> umid_logrecord_entry : (Replica.INSTANCE.getLogs().get_log_map().entrySet()))
        {
        	log_record = umid_logrecord_entry.getValue();
        	update_msg = log_record.getUpdateMessage();
        	prev = update_msg.getPrev();

        	// prev <= rep_ts
        	if(prev.compareTo(Replica.INSTANCE.getRepTs()) <= 0)
        		comp.put(umid_logrecord_entry.getKey(), log_record);
        }

        return comp;
	}