RFE: Request feature environment variable for RESTORECON_THREADS

[jboero]

I've noticed multiple Fedora/EL RPMs have scripts that do large restorecon operations during updates. Lately some of my larger volumes cause almost an hour for an RPM to finish upgrading. On a box with 88 CPUs my last update sat idle almost an hour with a single core at 99% and minimal I/O or network traffic. I would love to go fix all of these RPM scripts with parallel threads and get merges one by one but it makes much more sense if restorecon had an environment variable so I could just fix them all at once.

Example:

RESTORECON_THREADS=0 restorecon /path/to/restore

RESTORECON_THREADS=40 dnf update

I for one would set this globally anyway. Does this sound like a good idea? I'll even code up the PR myself. Would there be any support for this? I'll try it locally myself and see if it misbehaves.

[cgzones]

An alternative would be to change the default number of threads from 1 to 0 (i.e. $nproc).
I think I have not seen any threading issue for parallel relabeling yet.

[jboero]

It makes sense to me but others might have production issues if updating during application loads.