Allow the configuration of a maximum size limit per share.

Would that be per drive or total across all drives for that share?

 

I'm not sure if unRAID has support for 'quota' or not, but that might be one way of doing so. Although I think that's at a user level across an entire filesystem, and not at individual root directories levels.

Making a per user share and then setting quota for each user should also work.

 

I envisioned a single max for the entire share but a per disk max would allow more control.

On further though I don't think user quotas will work. I want the process accessing the share, e.g., Time Machine, to know the size of the share ahead of time.

I think this might work for providing size limitations, but I'm not a OS X user, so ...

 

Since you're using a Mac, if you wanted to provide limited space, maybe you could create a pre-allocated and fixed-size disk image file (.dmg?), then have the users/processes use that disk image file as a drive.

I tried using a Sparse Bundle Disk Image but Time Machine won't backup to a Disk Image.

 

I will have to use this hack: http://anitechtalk.wordpress.com/2010/07/19/time-machine-dns323/

for the time being.

I would like to see a 'per disk' option so that I could force each drive to maintain a certain percentage of free space to be used when replaying journaled events.

On further though I don't think user quotas will work. I want the process accessing the share, e.g., Time Machine, to know the size of the share ahead of time.

 

Further experience shows that user quotas will work for this application.