Basil> Hi folks, I need to delete a bunch of snapshots that were Basil> orphaned by CDOT when someone changed the schedule. It's a lot Basil> of data- 500gb for a 1tb LUN. How does ontap prioritize Basil> releasing these blocks after the delete? What's the best way in Basil> 8.2.3 to measure the impact, if any?

I wouldn't worry about it. The disk blocking freeing happens in the background and higher priority stuff will take precedence in my experience. Yes, it will put a load on the system, but if the system is beefy enough, or you have enough spindles and the disks aren't already too busy, you should be fine.

Maybe the output of:

statistics show-periodic -object disk:raid_group -instance /.....

will give you some idea of how busy you are?

Or you could do:

statistics start -object aggregate

wait a bit...

statistics show -object aggregate

and turn off stats with:

statistics stop -object aggregate

But honestly I'd just google 'ontap cdot vmstat' and look there for tricks to run. *grin*

John