Mirantis Container Cloud (MCC) becomes part of Mirantis OpenStack for Kubernetes (MOSK)!

Now, the MOSK documentation set covers all product layers, including MOSK management (formerly Container Cloud). This means everything you need is in one place. Some legacy names may remain in the code and documentation and will be updated in future releases. The separate Container Cloud documentation site will be retired, so please update your bookmarks for continued easy access to the latest content.

Increase memory limits for cluster components

When any MOSK component reaches the limit of memory resources usage, the affected pod may be killed by OOM killer to prevent memory leaks and further destabilization of resource distribution.

A periodic recreation of a pod killed by OOM killer is normal once a day or week. But if the alerts frequency increases or pods cannot start and move to the CrashLoopBack state, adjust the default memory limits to fit your cluster needs and prevent critical workloads interruption.

Note

For StackLight resources limits, refer to StackLight configuration parameters.

To increase memory limits on a MOSK cluster:

In the spec:providerSpec:value: section of cluster.yaml, add the resources:limits parameters with the required values for necessary MOSK components:

kubectl --kubeconfig <pathToManagementClusterKubeconfig> -n <projectName> edit cluster <clusterName>

The limits key location in the Cluster object can differ depending on component. Different cluster types have different sets of components that you can adjust limits for.

The following sections describe components that relate to a specific cluster type with corresponding limits key location provided in configuration examples. Limit values in the examples correspond to default product values.

Note

For StackLight resources limits, refer to Resource limits.

Limits for common components of any cluster type

No limits are set for the following components:

  • storage-discovery

The memory limits for the following components can be increased on the management and MOSK clusters:

  • client-certificate-controller

  • metrics-server

  • metallb

Note

  • For helm-controller, limits configuration is not supported.

  • For metallb, the limits key in cluster.yaml differs from other common components.

Common components for any cluster type

Component name

Configuration example

<common-component-name>

 
spec:
  providerSpec:
    value:
      helmReleases:
      - name: client-certificate-controller
        values:
          resources:
            limits:
              memory: 500Mi

metallb

 
spec:
  providerSpec:
    value:
      helmReleases:
      - name: metallb
        values:
          controller:
            resources:
              limits:
                memory: 200Mi
          speaker:
            resources:
              limits:
                memory: 500Mi

Limits for management cluster components

No limits are set for the following components:

  • baremetal-operator

  • baremetal-provider

  • cert-manager

The memory limits for the following components can be increased on a management cluster in the spec:providerSpec:value:kaas:management:helmReleases: section:

  • admission-controller

  • credentials-controller

  • event-controller

  • iam

  • iam-controller

  • kaas-exporter

  • kaas-ui

  • license-controller

  • release-controller

  • scope-controller

  • secret-controller

  • user-controller

The memory limits for the following components can be increased on a management cluster in the following sections:

  • spec:providerSpec:value:kaas:regional:provider:baremetal:helmReleases:

  • spec:providerSpec:value:kaas:regionalHelmReleases:

  • agent-controller

  • lcm-controller

  • mcc-cache

  • rbac-controller

  • squid-proxy

Limits for management cluster components

Component name

Configuration example

<mgmt-cluster-component-name>

 
spec:
  providerSpec:
    value:
      kaas:
        management:
          helmReleases:
          - name: release-controller
            values:
              resources:
                limits:
                  memory: 200Mi

baremetal-provider

 
spec:
  providerSpec:
    value:
      kaas:
        regional:
        - provider: baremetal
          helmReleases:
          - name: baremetal-provider
            values:
              cluster_api_provider_baremetal:
                resources:
                  requests:
                    cpu: 500m
                    memory: 500Mi

  • agent-controller

  • lcm-controller

  • rbac-controller

 
spec:
  providerSpec:
    value:
      kaas:
        regionalHelmReleases:
        - name: lcm-controller
          values:
            resources:
              limits:
                memory: 1Gi

mcc-cache

 
spec:
  providerSpec:
    value:
      kaas:
        regionalHelmReleases:
        - name: mcc-cache
          values:
            nginx:
              resources:
                limits:
                  memory: 500Mi
            registry:
              resources:
                limits:
                  memory: 500Mi
            kproxy:
              resources:
                limits:
                  memory: 300Mi

squid-proxy

 
spec:
  providerSpec:
    value:
      kaas:
        regional:
        - provider: baremetal
          helmReleases:
          - name: squid-proxy
            values:
              resources:
                limits:
                  memory: 1Gi