@Override
    public AgentInfo getAgentInfo(final String agentId, final long timestamp) {
        return getAgentInfo0(agentId, timestamp, agentInfoResultsExtractor, AgentInfoQuery.simple());
    }
Returns the information of the agent with its start time closest to the given timestamp

@param agentId
@param timestamp
@return
web/src/main/java/com/navercorp/pinpoint/web/dao/hbase/HbaseAgentInfoDao.java