Easy way to Purge / delete old recordings?

Is there an easy way to purge the DB and recorded files?

Back in ver 2.0 I use to be able to set the Disk space limit to like 1 or 2% and it would based on that purge out all the files / recordings until it reached that disk use %. I tried that in the 3.0, and did not appear to work.
I have 1TB drive set for the system. It had been using the global constant record.
I tried that trick and it did not seem to work. I install Webmin on it and used the file manager to purge out the recordings, Have my cameras set correctly for ONVIF trigger recording since all the cameras support that.
The system is now recording things. and have like 8 days of storage instead of like 2 hours.