[Enhancement] Integrate Prometheus and Grafana for monitoring in playground

[orenccl]

Closes #94

1. Add monitoring information to the README
2. Add Prometheus and Grafana settings to docker-compose
3. Add a basic Prometheus configuration file
4. Add a basic Grafana configuration, provision data source to Prometheus, and provision a dashboard to Gravitino Playground
5. Add port checks in playground.sh

Fixes

• Change - 18888:8888 to - "18888:8888" in the docker-compose.yaml for correct port mapping format.
• Change docker-compose ps to docker-compose ps -a to view all containers (including stopped ones).

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Note: Please ignore the high JVM Non-Heap Memory Usage and JVM Direct Memory Usage caused by my WSL2 environment.

[xunliu]

@orenccl Very coooool !!!! Thank you for your contribution.

[FANNG1]

cool

[orenccl]

At the first commit, gravitino-playground.json is a bit large(109KB). This file is a preset for the Gravitino dashboard. In the second commit, I reduced this file by minifying it, bringing the size down to 53KB (less than 50% of the original size).

Why this file is so large

1. I included almost every metric provided by Gravitino so others don't have to create panels themselves.
2. The preset dashboard provided on the official website is even 378KB. [Node Exporter Full with Node Name | Grafana Labs]

Therefore, I think 53KB is reasonable given the level of detail in the dashboard.

Below is current look:

Hope 53KB is fine. If not, I can reduce it further by removing rarely used metrics, like this.

Alternatively, I can split it into three different dashboards; each one will be smaller, but the total size will remain the same.

[orenccl]

@xunliu I’d love to hear your perspective.

[orenccl]

Here’s an example of minified JSON for those who may not be familiar with it.

Credit: https://devutils.com/guide/json-formattervalidator-7/

[orenccl]

Hi @xunliu

The home path has been configured to go directly to the Gravitino dashboard.