Issue with sched_getaffinity(0) in jails

[JonM]

Hi all,

I've not been able to find anything about this anywhere do I'm hoping someone can help?

I've been trying to install python packages from pip in a virtual environment I'm a jail, specifically zlib-ng but I'm coming across an issue where the use of sched_getaffinity in the packages causes the install to fail.

I did find a post from a few years ago on the freebsd forum about sched_getaffinity not working properly in truenas jails but unfortunately it was met with truenas isn't supported here and no replies.

Anyone else seen this issue and know of a work around or how to make sched_getaffinity work properly in a truenas jail (seems it's fine on plain freebsd)?

I'm really stuck without this python package.

Thanks for any help!
Jon

 

[Patrick M. Hausen]

AFAIK you cannot use the cpuset family of system calls inside a jail. Since a virtual environment does not touch the global install, how about trying the install from the NAS host system - into a venv directory located in the jail, of course.

I don't know if the software will subsequently work, but you could get past the install problem that way.

 

[JonM]

Ah that's a great idea! It'll mean installing python and stuff on the host though, which I've gathered is not advised. But I can undo all of that once I've got the package in my jail.

I'll give this a go tomorrow and report back on what happens

Thanks!

 

[Patrick M. Hausen]

Ah that's a great idea! It'll mean installing python and stuff on the host though, which I've gathered is not advised.

Python is a regular part of TrueNAS, no need to mess with the system:

Code:

root@freenas[~]# python --version
Python 3.9.16
root@freenas[~]# which python
/usr/local/bin/python

I would not have made that suggestion, otherwise.

 

[JonM]

Ah I see... This would need to be built for python 3.11 unfortunately.

Do you think there would be another way so I could avoid messing with the system?

I was thinking I might be able to track down the cached pip installation files and just edit the bit that calls sched_getaffinity but I've not managed it so far.

 

[Patrick M. Hausen]

Build in a FreeBSD VM, then copy to jail?

 

[JonM]

Boom, great shout. I'll give it a go.