# Cannot figure out why number of processes less than number of available CPUs

**URL:** <https://discuss.ray.io/t/cannot-figure-out-why-number-of-processes-less-than-number-of-available-cpus/8461>\
**Category:** Ray Core\
**Created:** [November 29, 2022, 6:00am UTC](https://discuss.ray.io/t/cannot-figure-out-why-number-of-processes-less-than-number-of-available-cpus/8461 "2022-11-29T06:00:01Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![xzf0kgb0bqr.cev2RWU](https://avatars.discourse-cdn.com/v4/letter/x/65b543/32.png) [@xzf0kgb0bqr.cev2RWU](https://discuss.ray.io/u/xzf0kgb0bqr.cev2RWU)\
**Post date:** [November 29, 2022, 6:00am UTC](https://discuss.ray.io/t/cannot-figure-out-why-number-of-processes-less-than-number-of-available-cpus/8461/1 "2022-11-29T06:00:01Z")

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- Medium: It contributes to significant difficulty to complete my task, but I can work around it.

I am using one node. I do:

_ray start --head --dashboard-host “0.0.0.0”_  
_ray status_

And in the usage section, I see:

_0.0/28.0 CPU_

Great, because I have 28 CPUs.

Now I do:

_ray stop_

And I see

_Stopped all 7 Ray processes._

As I understand it, Ray should make 1 process for each worker (see the question [here](https://discuss.ray.io/t/specify-the-number-of-worker-processes/2118) for example). I also double checked this by running a job, checking the dashboard and confirming that at most there only 7 workers.

i) Why are there not 28 processes?  
ii) How can I make Ray use 28 processes (i.e., one process per CPU)?

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**Author:** ![Stephanie\_Wang](https://sea2.discourse-cdn.com/flex020/user_avatar/discuss.ray.io/stephanie_wang/32/18_2.png) [@Stephanie\_Wang](https://discuss.ray.io/u/Stephanie_Wang)\
**Post date:** [November 29, 2022, 9:57pm UTC](https://discuss.ray.io/t/cannot-figure-out-why-number-of-processes-less-than-number-of-available-cpus/8461/2 "2022-11-29T21:57:39Z")

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The processes you are seeing are long-lived system-level processes that outlive individual Ray jobs. Ray automatically starts workers as needed based on submitted tasks and their resource requirements. Since there are no active jobs, there won’t be any workers.

Once you do submit a job, you should see worker processes start up. The actual number of worker processes is usually ~number of CPUs, but can be more or less depending on worker crashes and specific workload. There are two ways to submit a job:

1. Run a Python script that calls `ray.init()`. If you can access the head node, this is the simplest
2. Submit a packaged [Ray job](https://docs.ray.io/en/latest/cluster/running-applications/job-submission/index.html).

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<div class="post-metadata">

**Author:** ![xzf0kgb0bqr.cev2RWU](https://avatars.discourse-cdn.com/v4/letter/x/65b543/32.png) [@xzf0kgb0bqr.cev2RWU](https://discuss.ray.io/u/xzf0kgb0bqr.cev2RWU)\
**Post date:** [November 30, 2022, 10:22pm UTC](https://discuss.ray.io/t/cannot-figure-out-why-number-of-processes-less-than-number-of-available-cpus/8461/3 "2022-11-30T22:22:38Z")

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Very helpful. Thank you!!