Configuring the JVM Heap Size

The JVM heap size is configurable for the following containers: frontend, test-results, output-processing and contexts-service. You might want to consider increasing the heap size if you see "out of memory" errors, such as: Terminating due to java.lang.OutOfMemoryError: Java heap space.

Setting up

To be able to configure the JVM_HEAP_SIZE value for each container, you will first need to create customizations files on your services machine.

Create customizations files:

/etc/circleconfig/frontend/customizations
/etc/circleconfig/test-results/customizations
/etc/circleconfig/output-processor/customizations
/etc/circleconfig/contexts-service/customizations

In each customization file add the line below to export your desired JVM heap size:
```
export JVM_HEAP_SIZE=2g
```
Stop and restart CircleCI application from the Management Console dashboard (for example, your-circleci-hostname.com:8800)

Verify customization is applied

Once your installation has successfully restarted, you can confirm the configured value was applied correctly by running the following REPL commands per container:

frontend

sudo docker exec -it frontend lein repl :connect 6005

test-results

sudo docker exec -it test-results lein repl :connect 2719

output-processing

sudo docker exec -it picard-output-processor lein repl :connect 6007

And following are the outputs you should see:

(System/getenv "JVM_HEAP_SIZE") ;; should return what you have set above

(-> (java.lang.Runtime/getRuntime) (.maxMemory)) ;; return value should match with JVM_HEAP_SIZE