Recover disk space from mongodb

Mongodb Compact

db = db.getSiblingDB("admin"); 
dbs = db.runCommand({ "listDatabases": 1 }).databases

// Iterate through each database and get its collections. 
dbs.forEach(function(database) { 
    db = db.getSiblingDB(database.name); 
    print('OnDB: ' + database.name); 
    if(database.name == 'admin' || database.name == 'local'){
        print('Skipping: ' + database.name); 
    }else{
        db.getCollectionNames().forEach(function (collectionName) { 
        print('Compacting: ' + collectionName); 
            try{
              db.runCommand({ compact: collectionName });
            }catch(e){
                print(e); 
            }
    }); 
    }
});