Database Autonomy Service (DAS) uses machine learning and intelligent algorithms to monitor and predict core metrics of database instances. DAS also provides the one-click diagnostics feature to help find root causes.


  • A database instance is connected to DAS and is in the Accessed state.
  • The anomaly detection feature is available only for MySQL databases.
Note For more information about how to access a database instance, see the following topics:


DAS supports the following metrics for anomaly detection.

Metric Description
tps Calculation formula: (Com_commit + Com_rollback)/Uptime.
qps Calculation formula: Questions/Uptime.
active_session The number of active sessions.
delete_ps The average number of DELETE statements executed per second.
insert_ps The average number of INSERT statements executed per second.
update_ps The average number of UPDATE statements executed per second.
select_ps The average number of SELECT statements executed per second.
bytes_received The average number of bytes received from all clients per second.
bytes_sent The average number of bytes sent to all clients per second.
innodb_bp_hit The read hit rate of the InnoDB buffer pool. Calculation formula: (Innodb_buffer_pool_read_requests - Innodb_buffer_pool_reads)/Innodb_buffer_pool_read_requests × 100%.
innodb_data_written The average number of bytes that InnoDB writes per second.
innodb_data_read The average number of bytes that InnoDB reads per second.
mysql.innodb_log_writes The average number of physical writes to the InnoDB redo log file per second.
innodb_rows_deleted The average number of rows deleted from InnoDB tables per second.
innodb_rows_read The average number of rows read from InnoDB tables per second.
innodb_rows_inserted The average number of rows inserted into InnoDB tables per second.
innodb_rows_updated The average number of rows updated in InnoDB tables per second.
mysql.mem_usage The memory usage of the MySQL instance within the entire operating system.
mysql.cpu_usage The CPU utilization of MySQL processes. This metric can reach up to 100% for Alibaba Cloud database instances.


  1. Log on to the DAS console.
  2. In the left-side navigation pane, click Instance Monitoring.
  3. On the Instance Monitoring page, click a database engine tab.
  4. Find the instance that you want to view and choose Performance > Performance Trend in the Actions column.
  5. Click the Exception Detection tab.
    Note You can view exceptions on this tab.