Why is threads_count is ready only?

[joshdvir]

Hi,

Been starting to use Rage and I think it's great.

One issue I encountered is that when I have a long request with the current configuration of threads_count always being 1 the webserver is blocked getting more requests

Is there a reason threads_count is always 1?

Thanks

[rsamoilov]

Hey Josh,

Yes, Rage is purposefully single-threaded and quite similar to how Node.js works. There are a couple of reasons for this:

• We extensively use fibers. However, one limitation of fibers is that they have to be resumed from the same thread they were paused in, which makes scheduling a bit complicated.
• Threaded code is very difficult to work with. Using a single-threaded approach makes the codebase much simpler and more stable, and also removes a lot of overhead coming from synchronisation primitives.

If your workflow involves CPU-bound tasks, you can use the multi-worker mode to run Rage in multiple processes:

Rage.configure do
  config.server.workers_count = -1 # run as many workers as there are CPU cores
end

Can you share an example code snippet that blocks the webserver for you?

[joshdvir]

Thanks @rsamoilov for your replay.

I understand the logic behind what you are saying and it make sense.

My use case is working with LLM when in the controller, same as ChatGPT, when running in development specifically I can only do one request since there is one worker and that request can take a few seconds.

Per your recommendation I will increase the workers_count in development as well, of course production is by default.

Thanks

[rsamoilov]

It's not supposed to block, including in development. The only time it might block is when serving a first request after the code has been reloaded (which will be fixed in the next release).

If you log something at the top of your controller action and send multiple requests, you'll see that the requests are being processed in parallel even with one worker:

def index
  Rage.logger.info "processing..."
  # the rest of the logic
end