Monitor PCU groups in Astra DB
Astra DB provides insight into your PCU usage, including overall group usage and individual database activity.
You can monitor your PCU usage to ensure there are sufficient resources to support your databases and to manage costs by avoiding over-provisioning resources.
Prerequisites
Understand resource consumption in PCU groups
Databases in a PCU group use the group’s minimum capacity first.
If database usage scales beyond the minimum capacity, Astra DB can provision additional PCUs, billed at the HCU rate up to the group’s maximum capacity. As usage scales down, Astra DB deprovisions the excess PCUs accordingly.
If there are not enough resources available, database operations can experience higher latencies or timeouts.
View PCU group usage
To view usage for an entire PCU group, do the following:
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In the Astra Portal header, click settings Settings.
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In the Settings navigation menu, click the name of the current organization, and then select the organization where you want to view PCU group usage.
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In the Settings navigation menu, click Billing.
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In the Provisioned Capacity Unit groups section, locate the group you want to inspect.
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Click more_vert More, and then select View details to inspect the group’s configuration details, scoped databases, and usage metrics:
- PCU group details
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Name and description
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Cloud provider and region
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- Scoped databases
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The Name, Datacenter ID, and Status for each database scoped to the group.
To determine which databases are the most active in a PCU group, you must compare individual database usage. For more information, see View database usage.
- Key metrics
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Total latency by percentile: The time required for reads and writes against each database in the group.
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CPU utilization: The amount of CPU that the PCU group is using out of the group’s total amount of available CPU.
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Cache utilization: The amount of cache capacity the PCU group is currently using out of the group’s total cache capacity.
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View database usage
If a PCU group has multiple databases, you can inspect each database to determine which databases are most active and require the most resources.
To view usage for one database, do the following:
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In the Astra Portal navigation menu, click the database that you want to inspect.
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On the Overview tab, locate the Database details section, and then locate the Region list.
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To inspect usage for each region, click more_vert More, and then select Details.
Respond to usage concerns
After inspecting the PCU group and database usage, decide whether you need to modify your PCU groups. For example:
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To balance resource consumption and availability, you can edit your PCU groups to reassign databases or adjust allocated capacity.
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For resource-intensive or critical production workloads, DataStax recommends creating PCU groups dedicated to individual databases.
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To reduce costs, you can park flexible capacity PCU groups.
