Cluster configuration
The cluster configuration page in your PlanetScale dashboard allows you to monitor your cluster utilization and configure cluster settings for each branch in your database. You can:
- Adjust the cluster size and instance type (Metal vs network-attached storage)
- Configure the number of replicas
- Monitor cluster utilization with real-time graphs
- Modify PostgreSQL parameters
- Manage PostgreSQL extensions
- View and track configuration changes
These settings may only be changed by a database administrator or organization administrator.
Adjusting cluster size
To adjust your cluster size:
- From the PlanetScale organization dashboard, select the desired database
- Navigate to the Cluster configuration page from the menu on the left
- In the Cluster size section, click on the cluster size dropdown
- Select the new cluster size, (Metal or network-attached storage). If you select Metal, make sure you select the correct storage size.
- Click Queue instance changes > Apply changes to apply the new cluster size
Note
You cannot change the CPU architecture (AMD, Intel, ARM) of an existing cluster. To use a different architecture, you'll need to create a new branch with the desired cluster type.
Cluster resizing may take several minutes to complete. There will be no downtime during this process, but you cannot make additional configuration changes until the resize is finished.
Managing replicas
Replicas provide read scalability and high availability for your PostgreSQL database. Each production branch comes with 2 replicas by default.
Note
If you add additional replicas beyond the default 2, you will incur additional charges.
To adjust the number of replicas:
- From the PlanetScale organization dashboard, select the desired database
- Navigate to the Cluster configuration page from the menu on the left
- In the Cluster size section, use the dropdown Replicas to select your desired number of replicas
- Click Queue instance changes
- Click Apply changes to immediately begin the process to update the number of replicas
Monitoring cluster utilization
The cluster utilization graph provides real-time insights into your database's CPU and memory utilization. You can change the graph view to the past hour, 6 hours, 12 hours, day, or week. The graph also displays indicators when cluster settings were changed.
Note
If you are consistently close to 100% CPU, we recommend upsizing your cluster. Likewise, if you are consistently below 50% CPU, you can likely safely downgrade.
Parameters and settings
You can customize your PostgreSQL cluster's behavior in the Parameters tab on the Cluster configuration page. This allows you to configure the following settings:
- PSBouncer
- Resource usage
- Write-ahead logs (WAL)
- Query tuning
- Connections and authentication
- Failover
For more information about each setting, refer to the Parameters documentation.
Managing extensions
PostgreSQL extensions provide additional functionality for your database. The "Extensions" tab on the cluster configuration page allows you to view and enable/disable available extensions.
Extension management
- View currently installed extensions
- See available extensions for installation
- Enable or disable extensions
- Configure extension parameters
Monitoring configuration changes
The cluster configuration page provides visibility into all changes made to your cluster settings.
- Navigate to the Changes tab for the selected branch on the cluster configuration page
- View a chronological list of all configuration changes
- See details including:
- What was changed (cluster size, replicas, parameters)
- Previous and new values
- Status of the change
- Who initiated the change
- When the change was started and completed
Note
When updating a cluster's size, some parameters will automatically be adjusted. Each cluster size is associated with default parameter settings, changing the cluster size will also update those defaults. The exception to this is if you manually override a default parameter setting. In that case, a cluster size adjustment will not automatically change that setting.
Need help?
Get help from the PlanetScale Support team, or join our GitHub discussion board to see how others are using PlanetScale.