Jmodic and all,

first of all, thanks so much for all of the advises and time you guys are putting into this forum.

The reason I did ask those questions b/c I am new with PT, I read so many docs from Oracle and books and sometime it confused me so that may be I didn't ask the proper question and I apologize for that. I myself still try to learn from you guys and reading more books so hopefully one day it will be clearer.

I have performance problem with one of my database and I am trying to solve it. Right now, I am suspecting two problems on my database, one is I/O and the second one is LOCKING. I am still trying to see where and what part has been locking so I am digging and digging and sometime may be annoyingn to you guys. I apologize.

If you can give me direction so how to ping point the locking method, I would great appreciate ( I did find some articles on metalink but they are not too clear for me).