Effectively what you are differing is process based vs thread based. Threads share memory (e.g. SharedArrayBuffer) whereas processes don’t. Essentially they are the same thing categorically.
cluster
- One process is launched on each CPU and can communicate via IPC.
- Each process has it’s own memory with it’s own Node (v8) instance. Creating tons of them may create memory issues.
- Great for spawning many HTTP servers that share the same port b/c the
mastermain process will multiplex the requests to the child processes.
worker threads
- One process total
- Creates multiple threads with each thread having one Node instance (one event loop, one JS engine). Most Node API’s are available to each thread except a few. So essentially Node is embedding itself and creating a new thread.
- Shares memory with other threads (e.g.
SharedArrayBuffer) - Great for CPU intensive tasks like processing data or accessing the file system. Because NodeJS is single threaded, synchronous tasks can be made more efficient with workers