[FEATURE]: Integrate Throng Clustering for Performance and Concurrency

[Gautam25Raj]

Affected Apps / Packages

Server (apps/server), Infrastructure / Other

Is your feature request related to a problem?

Yes. The backend Express application runs on a single Node.js thread by default. This does not utilize multi-core host machines in staging/production environments (e.g. AWS, Render, Docker). A single-threaded setup experiences request queuing and high latency under concurrent load, and presents a single point of failure if a request causes an unhandled exception that crashes the process.

Describe the solution you'd like

We want to introduce clustering using throng to spawn a pool of Node.js worker processes that share the same port and handle incoming requests concurrently.

1. Master / Worker Topology:

   • Use throng in the server entry point index.ts.
   • The master process will read CLUSTERING_ENABLED and WEB_CONCURRENCY (worker count) configurations and boot the workers.
   • Each worker process will initialize its own database/Redis connections and start an instance of the Express server.

2. Cron & Background Job Isolation:

   • Background sync and maintenance cron jobs (e.g. githubSyncJob, viewsFlushJob) must only run on Worker 1 to avoid duplicate execution, race conditions, and excessive database locks.

3. Graceful Shutdown:

   • Implement process signal handlers (SIGTERM, SIGINT) in both the master and worker processes to perform a graceful teardown:
     • Stop the HTTP server from accepting new connections.
     • Complete in-flight requests with a reasonable timeout.
     • Disconnect from Redis and Prisma cleanly.

Describe alternatives you've considered

• Running multiple container instances: While container orchestration (e.g., ECS, Kubernetes) handles scaling well, application-level clustering inside each container optimizes cost and CPU utilization.
• Using PM2: PM2 is heavy and requires separate process monitors, whereas programmatic clustering with throng fits seamlessly inside a standard Node/TypeScript entry point.

Additional Context

• This setup will require adding CLUSTERING_ENABLED and WEB_CONCURRENCY configurations in config.ts and the .env configuration files.