Reference Application for workload monitoring¶
Available since 2.21.0 for non-MOSK managed clusters
For the feature support on MOSK deployments, refer to MOSK documentation: Deploy RefApp using automation tools.
Reference Application is a small microservice application that enables workload monitoring on non-MOSK managed clusters. It mimics a classical microservice application and provides metrics that describe the likely behavior of user workloads.
The application consists of the following API and database services that allow putting simple records into the database through the API and retrieving them:
- Reference Application API
Runs on StackLight nodes and provides API access to the database. Runs three API instances for high availability.
- PostgreSQL Since Container Cloud 2.22.0
Runs on worker nodes and stores the data on an attached PersistentVolumeClaim (PVC). Runs three database instances for high availability.
Before version 2.22.0, Container Cloud used MariaDB as the database management system instead of PostgreSQL.
StackLight queries the API measuring response times for each query. No caching is being done, so each API request must go to the database, allowing to verify the availability of a stateful workload on the cluster.
Reference Application requires the following resources on top of the main product requirements:
Up to 1 GiB of RAM per cluster
Up to 3 GiB of storage per cluster
The feature is disabled by default and can be enabled using the StackLight configuration manifest as described in StackLight configuration parameters: Reference Application.