Re: Introducing Guix to HPC at my institution

[Sébastien Lerique]

Hi Ludo, Simon, all,

> Will be back once I have some progress or more questions.

It turns out the HPC cluster I have access to has user namespaces 
activated \o/, so I'm looking into getting things running as an 
unpriviliged user to show other people how useful Guix can be 
(before approaching higher levels in the administration).

I have been through the following notes:

https://hpc.guix.info/blog/2017/09/reproducibility-and-root-privileges/
https://hpc.guix.info/blog/2017/10/using-guix-without-being-root/
http://issues.guix.gnu.org/34494

and am now following Guix's binary installation inside a user 
namespace. After decompressing the binary distribution of guix 
inside `~/local-guix`, my naïve next step was `unshare -mrf chroot 
~/local-guix 
gnu/store/mmhimfwmmidf09jw1plw3aw1g1zn2nkh-bash-static-5.0.16/bin/bash`.

But my knowledge of linux namespaces is hindering my next steps 
:). A few questions:

- after setting $GUIX_PROFILE and sourcing 
 `/root/.config/guix/current`, running `guix` warns with:

 GC Warning: pthread_getattr_np or pthread_attr_getstack failed 
 for main thread
 GC Warning: Couldn't read /proc/stat

 The first warning I don't know what to do with. About the 
 second: should I be binding `/proc` somehow?

- is it possible to create build users inside the user-namespaced 
 chroot?

- last but not least, how would I go about sharing this setup with 
 other users on the cluster? Ideally I would like to have a 
 non-priviliged build daemon that other users can call on. (Is 
 there such a thing as kernel group namespaces?)

Is this the right way to go for running guix without being root, 
or is there a better way?

Thanks for any guidance you might provide!
Best,
Sébastien