Add the ability to change the timeout period of a WSL instance

Environment

Windows build number: Microsoft Windows [Version 10.0.21343.1000]
Your Distribution version: Ubuntu 20.04
Whether the issue is on WSL 2 and/or WSL 1: Linux version 5.4.72-microsoft-standard-WSL2 (oe-user@oe-host) (gcc version 8.2.0 (GCC)) #1 SMP Wed Oct 28 23:40:43 UTC 2020

I have a linux server that provides multiple NFS network drives. As NFS performance under windows is abysmal I use wsl2 to mount the NFS drives.

Steps to reproduce

Mount any NFS drive using wsl.exe as starting point.

That is working well performance wise (which is why i am doing this, as NFS under native windows is abysmal) but the issue is whenever I mount a network drive through wsl2 it gets unmounted rather quickly after a short time of idling.

WSL logs:

Expected behavior

A mounted drive should not be unmounted except the user is specifically unmounting it.

I have solved this issue by adding a watch df -h at the end of the script, but that is in my opinion not the best solution.

Actual behavior

mounted network drives are not accessible anymore after a short time of idling and if you accidentially write to them you add a file to an empty folder which makes a remount impossible without clearing the folder.

Start by reproducing the issue with wsl.exe and an NFS mount on WSL2, then investigate where idle instances or mounts are timed out. Done means users can configure the timeout period and mounted network drives remain accessible for that configured duration without requiring watch df -h.