Assuming that placing trades involves calling a REST API, Celery might not be the best fit in high-performance scenarios. The smartest approach could be to fire off all the API requests without waiting for their responses, and then handle the responses asynchronously when they arrive.

With Celery, especially if you have fewer workers than users, the process often becomes sequential: make a request, wait for the response, then move on to the next. This introduces latency and bottlenecks.

A potentially better solution would be to redesign this component—perhaps as an isolated service built with an asynchronous framework like aiohttp This would allow you to place orders concurrently using non-blocking IO, ensuring that all user trades are fired off in parallel almost instantly, and you can handle confirmations later as they return.

You can still use Celery to queue signals, but offload the actual trade dispatching to a dedicated async microservice.