How to stop batch LLM jobs from slowing down real-time user requests

When applications send both interactive and batch requests to the same LLM provider, they compete for the same concurrency slots, which can degrade response times for users awaiting real-time replies. A simple concurrency limit cannot distinguish urgent requests from background tasks, so batch jobs can occupy all available slots and force interactive traffic to queue behind them. Engineers can address this through workload isolation — reserving dedicated capacity for each traffic class — rather than relying on a shared pool that treats all requests equally. Token-based admission control adds another layer by estimating each request's computational footprint before granting it access, preventing a few large jobs from monopolising resources. The broader principle is that effective overload management requires deciding not just how much work enters the system, but which work is permitted to proceed when demand exceeds available capacity.