Resource Considerations
This document describes resource considerations and limitations to be taken into account when provisioning and operating a9s PostgreSQL Service Instances.
The resource requirements of a Service Instance depend on the Template selected for its Service Plan. Each Template defines the topology (number of nodes) and the set of colocated processes. Templates that provide logging require a higher-memory VM type and more ephemeral disk than Templates without logging.
The Platform Operator must define matching vm_type and persistent_disk_type entries in the BOSH Cloud Config and
reference them from the Service Plan configuration. For guidance on Service Plans and Templates, see Service Plans
and Available Templates.
For guidance on Service Plans and Templates, see Service Plans and Available Templates.
Template Requirements
The resource requirements of a Service Instance depend on the Template selected for its Service Plan. The small,
medium, and large labels used for VM type and persistent disk type in the tables below refer to the example Cloud
Config entries defined in Update the Cloud Config.
Templates that provide logging require a higher-memory VM type than Templates without logging.
Templates that provide logging reserve at least 512 MB of RAM for the logging process, in addition to the memory required by the data service process itself. Provisioning 512 MB of additional headroom above this minimum is recommended, to comfortably absorb the logging overhead.
The following table lists resource requirements per VM, as well as totals across all nodes of a Service Instance.
- Per VM
- Totals
| Template name | Nodes | vCPUs | Logging | SSL | Min. RAM | Min. Persistent Disk | Min. Ephemeral Disk | Example VM Type | Example Persistent Disk Type |
|---|---|---|---|---|---|---|---|---|---|
postgresql17-single | 1 | 4 | Yes | No | ≥ 4.5 GB † | 10 GB | 10 GB | large | medium |
postgresql17-single-ssl | 1 | 4 | Yes | Yes | ≥ 4.5 GB † | 10 GB | 10 GB | large | medium |
postgresql17-single-no-logging | 1 | 2 | No | No | ≥ 4 GB | 10 GB | 10 GB | small | medium |
postgresql17-single-no-logging-ssl | 1 | 2 | No | Yes | ≥ 4 GB | 10 GB | 10 GB | small | medium |
postgresql17-replica | 3 | 4 | Yes | No | ≥ 4.5 GB † | 10 GB | 10 GB | large | medium |
postgresql17-replica-ssl | 3 | 4 | Yes | Yes | ≥ 4.5 GB † | 10 GB | 10 GB | large | medium |
postgresql15-single | 1 | 4 | Yes | No | ≥ 4.5 GB † | 10 GB | 10 GB | large | medium |
postgresql15-single-ssl | 1 | 4 | Yes | Yes | ≥ 4.5 GB † | 10 GB | 10 GB | large | medium |
postgresql15-single-no-logging | 1 | 2 | No | No | ≥ 4 GB | 10 GB | 10 GB | small | medium |
postgresql15-single-no-logging-ssl | 1 | 2 | No | Yes | ≥ 4 GB | 10 GB | 10 GB | small | medium |
postgresql15-replica | 3 | 4 | Yes | No | ≥ 4.5 GB † | 10 GB | 10 GB | large | medium |
postgresql15-replica-ssl | 3 | 4 | Yes | Yes | ≥ 4.5 GB † | 10 GB | 10 GB | large | medium |
| † Includes the RAM reserved for the logging process. See the note above. | |||||||||
| Template name | Nodes | vCPUs | Logging | SSL | Min. RAM | Min. Persistent Disk | Min. Ephemeral Disk |
|---|---|---|---|---|---|---|---|
postgresql17-single | 1 | 4 | Yes | No | ≥ 4.5 GB † | 10 GB | 10 GB |
postgresql17-single-ssl | 1 | 4 | Yes | Yes | ≥ 4.5 GB † | 10 GB | 10 GB |
postgresql17-single-no-logging | 1 | 2 | No | No | ≥ 4 GB | 10 GB | 10 GB |
postgresql17-single-no-logging-ssl | 1 | 2 | No | Yes | ≥ 4 GB | 10 GB | 10 GB |
postgresql17-replica | 3 | 12 | Yes | No | ≥ 13.5 GB † | 30 GB | 30 GB |
postgresql17-replica-ssl | 3 | 12 | Yes | Yes | ≥ 13.5 GB † | 30 GB | 30 GB |
postgresql15-single | 1 | 4 | Yes | No | ≥ 4.5 GB † | 10 GB | 10 GB |
postgresql15-single-ssl | 1 | 4 | Yes | Yes | ≥ 4.5 GB † | 10 GB | 10 GB |
postgresql15-single-no-logging | 1 | 2 | No | No | ≥ 4 GB | 10 GB | 10 GB |
postgresql15-single-no-logging-ssl | 1 | 2 | No | Yes | ≥ 4 GB | 10 GB | 10 GB |
postgresql15-replica | 3 | 12 | Yes | No | ≥ 13.5 GB † | 30 GB | 30 GB |
postgresql15-replica-ssl | 3 | 12 | Yes | Yes | ≥ 13.5 GB † | 30 GB | 30 GB |
| † Includes the RAM reserved for the logging process. See the note above. | |||||||
WAL accumulation and optional continuous archiving mean that disk usage can grow beyond the raw data size. Replica nodes each hold a full copy of the dataset.