AnalyticDB:Manage coordinator node resources

Notes

Changing coordinator node specifications may interrupt SQL execution. It cannot be resumed even after the change is complete. Perform this operation during an appropriate period of time.

Suggestions

The default specifications can meet most business requirements. However, if your business scenario involves a large number of connections or your transaction processing workloads require low latency and high throughput, you may need higher specifications.

You can change specifications of coordinator node resources in the following aspects:

• Instance monitoring data

  You can view the usage of coordinator node resources on the Coordinator Node tab of the Monitoring and Alerts page. If the CPU utilization or memory usage of coordinator nodes remains persistently high, upgrade the specifications of coordinator node resources.

• Typical workloads

  For a TPC-C test of typical transaction processing workloads, the test performance varies based on the specifications of coordinator node resources. For more information, see TPC-C.

  The following table provides an example of performance parameters for an instance that has 32 compute nodes of 4 cores and 32 GB memory.

  Coordinator node resources (CUs)	Concurrency	Performance (tpmC)	Linear ratio
  8	32	18361.97	1.0
  16	64	33536.84	1.83
  32	128	58787.01	3.20

  The preceding test result shows that higher specifications of coordinator node resources can significantly improve system performance for transaction processing workloads. However, an increase in the specifications of coordinator node resources to more than 32 compute units (CUs) hardly improves the performance of workloads. This is because the disk bandwidth of compute nodes reaches the upper limit in this case. Therefore, we recommend not setting the specifications of coordinator node resources to more than 32 CUs. If you require more than 32 CUs of coordinator node resources, contact technical support.

Add coordinator node resources

1. Log on to the AnalyticDB for PostgreSQL console.
2. In the upper-left corner of the console, select a region.
3. Find the instance that you want to manage and click the instance ID.

4. In the upper-right corner of the Basic Information page, choose Manage Instance > Change Master Node Specifications > Add Coordinator Node Resources.

   For an instance in Serverless mode, select I am aware of the impact of this operation and agree to continue it. and click OK in the Info dialog box.

   Important

   After you submit a specification change request, the current SQL statements are interrupted. The SQL statements cannot be resumed even after the change is complete.

5. On the Upgrade/Downgrade page, select the appropriate specifications for Coordinator Node Resources, read and accept the Terms of Service, and then click Buy Now.

   Important

   If the coordinator node resources is more than 8 CUs, you are charged on a pay-as-you-go basis. For the billing details, see Pricing.

6. Return to the Instances page and wait for the instance state to change to Running.

Remove coordinator node resources

1. Log on to the AnalyticDB for PostgreSQL console.
2. In the upper-left corner of the console, select a region.
3. Find the instance that you want to manage and click the instance ID.

4. In the upper-right corner of the Basic Information page, choose Manage Instance > Change Coordinator Node Specifications > Remove Coordinator Node Resources.

   For an instance in Serverless mode, select I am aware of the impact of this operation and agree to continue it. and click OK in the Info dialog box.

   Important

   After you submit a specification change request, the current SQL statements are interrupted. The SQL statements cannot be resumed even after the change is complete.

5. On the Upgrade/Downgrade page, select a value for Coordinator Node Resources, read and accept the Terms of Service, and then click Buy Now.

6. Return to the Instances page and wait for the instance state to change to Running.