Purge/Archive in Service Manager

Hello All,

I am looking out for some case studies on the HPSM Purge/Archive option. I am looking at

1)what best practices were being used and what wa the result of using the Purge option.

2)  how many records were being considered for purge and what frequency was set.

3) What housekeeping was performed after the Tickets were purged from production.

4) How were the format control validation avoided while using the purging option.