Cassandra configuration

This section describes the Cassandra configuration through the Tungsten Fabric Operator custom resource.

Cassandra resource limits configuration

By default, Tungsten Fabric Operator sets up the following resource limits for Cassandra analytics and configuration StatefulSets:

Limits:
  cpu:     8
  memory:  32Gi
Requests:
  cpu:     1
  memory:  16Gi

This is a verified configuration suitable for most cases. However, if nodes are under a heavy load, the KubeContainerCPUThrottlingHigh StackLight alert may raise for Tungsten Fabric Pods of the tf-cassandra-analytics and tf-cassandra-config StatefulSets. If such alerts appear constantly, you can increase the limits through the TFOperator CR. For example:

spec:
  controllers:
    cassandra:
      deployments:
      - name: tf-cassandra-config
        resources:
          limits:
            cpu: "12"
            memory: 32Gi
          requests:
            cpu: "2"
            memory: 16Gi
      - name: tf-cassandra-analytics
        resources:
          limits:
            cpu: "12"
            memory: 32Gi
          requests:
            cpu: "2"
            memory: 16Gi

Custom configuration

To specify custom configurations for Cassandra clusters, use the configOptions settings in the TFOperator CR. For example, you may need to increase the file cache size in case of a heavy load on the nodes labeled with tfanalyticsdb=enabled or tfconfigdb=enabled:

spec:
  controllers:
    cassandra:
       deployments:
       - name: tf-cassandra-analytics
         configOptions:
             file_cache_size_in_mb: 1024