Infrastructure Pods and Resource Management

During the installation procedure you will be able to provide information on how to best "operationalize" your infrastructure. Through the configuration of --node-selector, --toleration and --operator-resources you will be able to drive the operator Pods scheduling and to be able to assign resources.

The usage of these advanced properties assumes you’re familiar with the Kubernetes Scheduling concepts and configurations.

The aforementioned flags setting will work both with OLM installation and regular installation.

Scheduling

Node Selectors

The most basic operation we provide is to let you assign Camel K operator Pods to a specific cluster Node via --node-selector option. The functionality is based on NodeSelector Kubernetes feature. As an example, you can schedule Camel K infra Pods to a specific Node of your cluster:

kamel install --node-selector kubernetes.io/hostname=ip-172-20-114-199.ec2.internal ...

The option will accept any key=value pair as specified and supported by Kubernetes. You can specify more than one node-selector.

Tolerations

The --toleration option will let you tolerate a Camel K infra Pod to support any matching Taint according the Taint and Toleration Kubernetes feature. As an example, let’s suppose we have a node tainted as "dedicated=camel-k:NoSchedule". In order to allow the infra Pods to be scheduled on that Node we can provide the following option during installation procedure:

kamel install --toleration dedicated=camel-k:NoSchedule ...

The option accept a value in the following format Key[=Value]:Effect[:Seconds] where the values in squared bracket are considered optional and Effect must admit any of the Taints accepted values: NoSchedule, PreferNoSchedule, NoExecute. You can specify more than one toleration.

Resources

While installing the Camel K operator, you can also specify the resources requests and limits to assign to the operator Pod with --operator-resources option. The option will expect the configuration as required by Kubernetes Resource Management.

kamel install --operator-resources requests.cpu=256m --operator-resources limits.cpu=500m --operator-resources limits.memory=512Mi ...

The value expected by the option are in the form requestType.requestResource=value where requestType must be either requests or limits, requestResource must be either cpu or memory and value expressed in the numeric value as expected by the resource. You can specify more than one operator-resources.

if you specify a limit, but does not specify a request, Kubernetes automatically assigns a request that matches the limit.

Suggested configuration

The main contributor to compute resources consumption is likely to be the Maven builds that are performed in the operator Pod (assuming you use the default build strategy). So the resource requirements should be defined accordingly. The following requirements are sensible defaults that should work in most cases:

resources:
  limits:
    cpu: "1"
    memory: 1Gi
  requests:
    cpu: 500m
    memory: 512Mi

Note that if you plan to perform native builds, then the memory requirements must be increased significantly. Also, the CPU requirements are rather "soft", in the sense that it won’t break the operator, but it’ll perform slower in general.