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Monitoring Optimizer Hub

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You can monitor your Optimizer Hub using the standard Kubernetes monitoring tools: Prometheus and Grafana. Optimizer Hub components are already configured to expose key metrics for scraping by Prometheus.

In your production systems, you will likely want to use your existing Prometheus and Grafana instances to monitor Optimizer Hub. If you are just evaluating Optimizer Hub, you may want to install a separate instance of Prometheus and Grafana to just monitor your test instance of Optimizer Hub.

Monitoring Optimizer Hub assumes you have a Prometheus and Grafana available, or install one within your Kubernetes cluster.

Grafana Dashboard

You can find a Grafana configuration file cnc_dashboard.json in

Retrieving Optimizer Hub Logs

All Optimizer Hub components, including third-party ones, log some information to stdout. These logs are very important for diagnosing problems.

You can extract individual logs with the following command:

$ kubectl -n my-opthub logs {pod}

However by default Kubernetes keeps only the last 10 MB of logs for every container, which means that in a cluster under load the important diagnostic information can be quickly overwritten by subsequent logs.

You should configure log aggregation from all Optimizer Hub components, so that logs are moved to some persistent storage and then extracted when some issue needs to be analyzed. You can use any log aggregation One suggested way is to use Loki. You can query the Loki logs using the logcli tool.

Here are some common commands you can run to retrieve logs:

  • Find out host and port where Loki is listening

    $ export LOKI_ADDR=http://{ip-adress}:{port}
  • Get logs of all pods in the selected namespace

    $ logcli query --since 24h --forward --limit=10000 '{namespace="zvm-dev-3606"}'
  • Get logs of a single application in the selected namespace

    $ logcli query --since 24h --forward --limit=10000 '{namespace="zvm-dev-3606" app="compile-broker"}'
  • Get logs of a single pod in the selected namespace

    $ logcli query --since 24h --forward --limit=10000 '{namespace="zvm-dev-3606",pod="compile-broker-5fd956f44f-d5hb2"}'

Extracting Compilation Artifacts

Optimizer Hub uploads compiler engine logs to the blob storage. By default only logs from failed compilations are uploaded.

You can retrieve the logs from your blob storage, which uses the directory structure <compilationId>/<artifactName>. The <compilationId> starts with the VM-Id which you can find in connected-compiler-%p.log:

# Log command-line option -Xlog:concomp=info:file=connected-compiler-%p.log::filesize=500M:filecount=20 # Example: [0.647s][info ][concomp] [ConnectedCompiler] received new VM-Id: 4f762530-8389-4ae9-b64a-69b1adacccf2