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by puzzle 3352 days ago
The Kubernetes docs don't say anything about having to use privileged containers for GPU support. Privileged containers are given tens of Linux capabilities; which of those are actually needed in your setup? Or, conversely, which specific step would fail for an unprivileged container?

Just because I want to use a GPU shouldn't require the power to change the clock, switch UIDs, chown files, mess with logs, reboot the machine, etc.
1 comments
marcoceppi 3352 days ago
Since the GPU libraries are hosted on the node, privileged flag is typically required to make that possible. I'm sure there will be improvements to not require privileged, but today it's mostly a requirement to get anything useful out of containers tapping into GPU.

That said, if you set the allow-privileged flag to false GPU drivers will still be installed but you may not be able to make use of the cuda cores

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puzzle 3352 days ago
That's weird, because all the times I tried the experimental support, it didn't need privileged containers. From the YAML files, it looks like it's using hostPath directories, but those don't require special privileges, unless you need to write to them:

https://kubernetes.io/docs/concepts/storage/volumes/#hostpat...

I suspect that there is a bug somewhere.

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puzzle 3352 days ago
Ah, wait:

https://github.com/madeden/blogposts/blob/master/k8s-gpu-clo...

You don't need to mount the /dev entries into the container at all. The experimental support creates them automatically for you when you are using GPU resources. Perhaps it's device nodes, not the libraries that required privileges?

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samnco 3351 days ago
Hello,

OK I gave it a try and you are absolutely right. For the nvidia-smi, I could run it the /dev/nvidia0, which is cool.

I was also able to run it unprivileged. I guess my mistake was to believe the example from the docs and not test without.

Thanks for sharing that, I'll update my charts and the post accordingly.

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puzzle 3351 days ago
Awesome! Happy to hear that more containers will run without unneeded privileges.
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samnco 3352 days ago
Aaah that is interesting. Let me dive into this later today and test my charts without that. It would actually make my life way easier for charting. I got that from a very early stage work and never questioned it again (the /dev stuff). Thanks for pointing that out.
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