< Marvin> I have two process workers one named one unnamed l Prefect Community #ask-marvin

<@ULVA73B9P> I have two process workers (one name...

Santiago Gutierrez

04/20/2026, 11:59 PM

@Marvin I have two process workers (one named, one unnamed) listening to the same work pool, but one of them is started with:

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prefect worker start -n named_worker -p same_work_pool -q my_different_queue

I am using this yaml for a particular deployment:

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deployments:
  - name: my_deployment
    
    concurrency_limit: null
    description: "The eds dev workflow"
    entrypoint: flows/my_flow.py:my_flow
    work_pool:
      name: same_work_pool
      work_queue_name: my_different_queue
      job_variables:
        working_dir: ...

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How can I point this deployment so that jobs are only sent to the `named_worker` process worker?

Marvin

04/20/2026, 11:59 PM

✅ thought for 336.8 seconds

Marvin

04/21/2026, 12:05 AM

Short answer: you can’t pin a deployment to a specific worker instance by name in Prefect 3.x. Routing is done by work pool and work queue. If two workers poll the same pool/queue, either can pick up the run. In your setup, the unnamed worker (started without

-q

) will poll all queues in

same_work_pool

, including

my_different_queue

, so it will compete with

named_worker

. Ways to ensure only

named_worker

runs this deployment: - Restrict the other worker’s queues - Start the unnamed worker with explicit queues that do not include `my_different_queue`:

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prefect worker start -p same_work_pool -q default -q some_other_queue

- Keep

named_worker

as-is:

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prefect worker start -n named_worker -p same_work_pool -q my_different_queue

- Or isolate via a dedicated work pool - Create a pool just for

named_worker

and update the deployment’s

work_pool.name

to that pool:

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prefect work-pool create "dedicated-pool" --type process
  prefect worker start -n named_worker -p dedicated-pool -q my_different_queue

- Update your deployment YAML:

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deployments:
    - name: my_deployment
      entrypoint: flows/my_flow.py:my_flow
      work_pool:
        name: dedicated-pool
        work_queue_name: my_different_queue

Notes: - Setting

concurrency_limit

or queue concurrency won’t force runs to a specific worker; it just limits total concurrent runs across all workers polling that queue. - A worker started without

-q

polls all queues in the pool by default. References: - Workers concept (includes

-q

behavior): Workers - Work pools and queues: Work Pools and Queues - CLI reference for `prefect worker start`: Worker CLI

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