The PolarDB console allows you to monitor a variety of performance metrics and view monitoring data at intervals of seconds. You can monitor the status of your clusters and locate faults based on the monitoring data.

Performance monitoring

  1. Log on to the PolarDB console.
  2. In the upper-left corner of the console, select the region in which the cluster that you want to manage is deployed.
  3. Find the cluster and click the cluster ID.
  4. In the left-side navigation pane, choose Diagnostics and Optimization > Monitoring.
  5. View the monitoring information about a Cluster, Compute Node, or Advanced Monitoring based on your needs. For more information, see Metrics.
    • To monitor cluster performance, click the Cluster tab. Specify a monitoring period in the date and time picker and click OK.Cluster performance monitoring
    • To monitor compute node performance, click the Compute Node tab and select a node from the drop-down list. Specify a monitoring period in the date and time picker and click OK. Node performance monitoring

Metrics

Category Metric Description
Cluster Storage Displays the usage of data space, log space, temporary space, and WAL log space.
CPU Usage Displays the CPU utilization of each node.
Memory Usage Displays the memory usage of each node.
Node TPS Displays the number of transactions per second of the selected node, including the number of committed transactions per second, deadlocked transactions per second, and rollback transactions per second.
CPU Usage Displays the CPU utilization of the selected node.
Memory Usage Displays the memory usage of the selected node.
Connections Displays the total number of current connections, the number of active connections, and the number of idle connections for the selected node.
Scanned Rows Displays the numbers of rows that are inserted, read, updated, deleted, and returned per second on the selected node.
Maximum Database Age Displays the difference between the transaction IDs of the earliest and latest transactions in the database.
I/O Throughput Displays the total I/O throughput, I/O read throughput, and I/O write throughput of the selected node.
IOPS Displays the following IOPS types of the selected node: the total IOPS, read IOPS, and write IOPS.
Cache Displays the cache reads per second and disk reads per second of the selected node.
Cache Hit Ratio Displays the cache hit ratio of the selected node.
Temporary Files Displays the number and total size of temporary files on the selected node.

FAQ

  • Why is the QPS that is displayed on the Monitoring page approximately 10 when the service traffic of my cluster is 0?

    The monitoring, log collection, and administration tasks that run in the system background generate approximately 10 queries per second. This has little impact on the performance of your cluster.

  • How do I reduce the CPU utilization when the CPU utilization is excessively high?
    We recommend that you perform the following steps:
    • Check whether a large number of slow requests exist. If a large number of slow requests exist, we recommend that you optimize slow SQL statements first.
    • Check whether the trend of the CPU utilization curve is consistent with that of the QPS or TPS curve. If the curves are consistent, the issue is caused by high concurrency of transactions. In this case, we recommend that you upgrade the configuration of your cluster.
    • If no slow requests exist and the trend of the CPU utilization curve is inconsistent with that of the QPS or TPS curve, submit a ticket for technical support.
  • What do I do when the number of connections is much greater than the number of active connections?

    You can specify smaller values for the wait_timeout and interactive_timeout parameters to accelerate the release of idle connections. We recommend that you close the connections that are no longer in use in time to reduce the number of idle connections.

Related API operations

API Description
DescribeDBClusterPerformance Queries the performance data of a PolarDB cluster.
DescribeDBNodePerformance Queries the performance data of a specified node in a specified PolarDB cluster.
DescribeDBClusterMonitor Queries the interval for collecting the monitoring data of a specified PolarDB cluster.
ModifyDBClusterMonitor Changes the interval for collecting the monitoring data of a specified PolarDB cluster.