An ASP.NET Core endpoint needs to perform CPU-heavy report generation. How would you design that?

CPU-bound work in an ASP.NET Core API

Decide how to handle CPU-heavy work in an API without damaging request throughput or making the system unreliable.

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I would avoid doing heavy CPU work directly inside the request if it can take significant time. For small calculations it may be fine, but report generation or image processing can tie up server resources and slow other requests. A better design is often to enqueue the work, return a job ID, and let a background worker process it with controlled concurrency. The API can expose status and download endpoints.

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CPU-bound work, request latency, background processing, queue design, bounded concurrency, and operational ownership.

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Decide how to handle CPU-heavy work in an API without damaging request throughput or making the system unreliable. It matters in real backend work because load, cancellation, retries, and dependency latency decide whether the API stays predictable under pressure. The practical angle is cPU-bound work, request latency, background processing, queue design, bounded concurrency, and operational ownership, tied to a concrete production decision.
I would avoid doing heavy CPU work directly inside the request if it can take significant time. For small calculations it may be fine, but report generation or image processing can tie up server resources and slow other requests. A better design is often to enqueue the work, return a job ID, and let a background worker process it with controlled concurrency. The API can expose status and download endpoints.
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For example, if a user requests a large export, I would create a report job record, put a message on a queue, and have workers generate the file. That gives me retries, progress tracking, cancellation, and a place to store failures. The trade-off is a more complex user flow: the result is not immediate, and the UI needs job status. But the system becomes more predictable under load because I can control how many reports run at once.

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Running heavy CPU work inline with no timeout or concurrency limit.
Wrapping report generation in Task.Run and assuming the problem is solved.
Not designing status, retry, or failure visibility.
Letting many jobs run in parallel until the server CPU is saturated.
Forgetting storage cleanup for generated files.

An ASP.NET Core endpoint needs to perform CPU-heavy report generation. How would you design that?

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