Hi Visvanath,
I think its best to ignore the OU link, since that dates from before Moodle had its own integrated XHProf.
The Moodle integration comes out of the box and will work mysql, you only need to ensure that the XHProf php extension is installed and then enabling profiling.
One thing to watch out for on mysql is ensuring that max_packet_size is large enough because IIRC it stores the profiling data in the database.
Let us know how you get on?