Process to reclaim free space from mongodb ,replication is there
Once and for all: The database repair command is potentially harmful and is advised against


  You should not use repairDatabase for data recovery unless you have no other option.


And


  This command obtains a global write lock and will block other operations until it has completed.


Hardly what you want in a production system. I already answered a similar, though not identical question. However, the same rules apply. Read the part on capacity planning closely.

And honestly: if you have to ask for the procedure, you really, really, really should not even think about executing it. Even when you get a detailed How-To, you will lack any knowledge of potential side effects. If it is a production system, get yourself a DBA. It is worth it.