Setting the OAM Server Memory Parameters

7.1.7 Setting the OAM Server Memory Parameters

By default, the java memory parameters assigned to the oam-cluster are very small. The minimum recommended values are -Xms4096m -Xmx8192m. However, Oracle recommends you to set these to -Xms8192m -Xmx8192m in a production environment.

Navigate to the /output/weblogic-domains/<domain_uid> directory:

cd $WORKDIR/kubernetes/create-access-domain/domain-home-on-pv/output/weblogic-domains/<domain_uid>

For example:

cd $WORKDIR/kubernetes/create-access-domain/domain-home-on-pv/output/weblogic-domains/accessdomain

Take a backup of the domain.yaml:
```
cp domain.yaml domain.yaml.orig
```
Edit the domain.yaml file and inside name: accessdomain-oam-cluster, add the memory setting as below:
```
  serverPod:
    env:
    - name: USER_MEM_ARGS
      value: "-XX:+UseContainerSupport -Djava.security.egd=file:/dev/./urandom -Xms8192m -Xmx8192m"
    resources:
     limits:
      cpu: "2"
      memory: "8Gi"
     requests:
      cpu: "1000m"
      memory: "4Gi"
```
For example:
```
apiVersion: weblogic.oracle/v1
kind: Cluster
metadata:
  name: accessdomain-oam-cluster
  namespace: oamns
spec:
  clusterName: oam_cluster
  serverService:
    precreateService: true
  serverPod:
    env:
    - name: USER_MEM_ARGS
      value: "-XX:+UseContainerSupport -Djava.security.egd=file:/dev/./urandom -Xms8192m -Xmx8192m"
    resources:
     limits:
      cpu: "2"
      memory: "8Gi"
     requests:
      cpu: "1000m"
      memory: "4Gi"
  replicas: 1
```
Note:
Administrators should be aware of the following:
- The above CPU and memory values are for examples only. For Enterprise Deployments, please review the performance recommendations and sizing requirements in Enterprise Deployment Guide for Oracle Identity and Access Management in a Kubernetes Cluster .
- Limits and requests for CPU resources are measured in CPU units. One CPU in Kubernetes is equivalent to 1 vCPU/Core for cloud providers, and 1 hyperthread on bare-metal Intel processors. An “m” suffix in a CPU attribute indicates ‘milli-CPU’, so 500m is 50% of a CPU. Memory can be expressed in various units, where one Mi is one IEC unit mega-byte (1024^2), and one Gi is one IEC unit giga-byte (1024^3). For more information, see Resource Management for Pods and Containers, Assign Memory Resources to Containers and Pods, and Assign CPU Resources to Containers and Pods
- The parameters above are also utilized by the Kubernetes Horizontal Pod Autoscaler (HPA). For more details on HPA, see Kubernetes Horizontal Pod Autoscaler.
- If required you can also set the same resources and limits for the accessdomain-policy-cluster.

In the domain.yaml locate the section of the file starting with adminServer:. Under the env: tag add the following CLASSPATH entries. This is required for running the idmconfigtool from the Administration Server:

- name: CLASSPATH
  value: "/u01/oracle/wlserver/server/lib/weblogic.jar"

For example:

  # adminServer is used to configure the desired behavior for starting the administration server.
  adminServer:
    # adminService:
    #   channels:
    # The Admin Server's NodePort
    #    - channelName: default
    #      nodePort: 30701
    # Uncomment to export the T3Channel as a service
    #    - channelName: T3Channel
    serverPod:
      # an (optional) list of environment variable to be set on the admin servers
      env:
      - name: USER_MEM_ARGS
        value: "-Djava.security.egd=file:/dev/./urandom -Xms512m -Xmx1024m "
      - name: CLASSPATH
        value: "/u01/oracle/wlserver/server/lib/weblogic.jar"

If required, you can add the optional parameter maxClusterConcurrentStartup to the spec section of the domain.yaml. This parameter specifies the number of managed servers to be started in sequence per cluster.

For example,if you updated the initialManagedServerReplicas to 4 in create-domain-inputs.yaml and only had 2 nodes, then setting maxClusterConcurrentStartup: 1 will start one managed server at a time on each node, rather than starting them all at once. This can be useful to take the strain off individual nodes at startup.
Below is an example with the parameter added:
```
apiVersion: "weblogic.oracle/v9"
kind: Domain
metadata:
  name: accessdomain
  namespace: oamns
  labels:
    weblogic.domainUID: accessdomain
spec:
  # The WebLogic Domain Home
  domainHome: /u01/oracle/user_projects/domains/accessdomain
  maxClusterConcurrentStartup: 1

  # The domain home source type
  # Set to PersistentVolume for domain-in-pv, Image for domain-in-image, or FromModel for model-in-image
  domainHomeSourceType: PersistentVolume
  ....
```
Save the changes to domain.yaml