Logging in provides users data customized to their specific account and provides the system a way to control usage.
登录模块能提供根据特定帐户定制的用户数据，并为系统提供了一个控制使用的途径。
2
Rather than add the latency, complexity, and overhead of summarizing, logging, and processing information, it is often better to provide direct access to live system performance data.
由于不增加延迟、复杂性以及合计、日志及处理信息的开销，提供到即时系统数据的直接访问通常会更好。
3
RRDtool is an open source, high performance datalogging and graphing system for time series data.