Active IQ Unified Manager （ UM ）
- 用户可以登录到 Web 界面，但不会加载页面的对象数据
- MySQL 错误日志中会显示此类型的错误：
2020-05-15T15:53:43.132646Z 18 [Warning] InnoDB: Difficult to find free blocks in the buffer pool (75980 search iterations)! 75980 failed attempts to flush a page! Consider increasing the buffer pool size. It is also possible that in your Unix version fsync is very slow, or completely frozen inside the OS kernel. Then upgrading to a newer version of your operating system may help. Look at the number of fsyncs in diagnostic info below. Pending flushes (fsync) log: 0; buffer pool: 0. 244072 OS file reads, 20565 OS file writes, 783 OS fsyncs. Starting InnoDB Monitor to print further diagnostics to the standard output.