In order to get a clean database configuration, I add the following two hidden parameters in my 10.2.0.1 parameter file.
Do not hurl that loud, I hear you from here!
Well, as I said already about the _pga_max_size, I never recommend using hidden parameters when you can do the same without.
However, I am going to communicate those parameters, and the metalink notes referencing them.
You will need them to have a cleaner 10.2.0.1 installation
This parameter prevent Heap size 2800K exceeds notification threshold errors in the alert log and user trace dumps.
Note: 330239.1 Bugs: 4286095, 4390265
In case you do not use dataguard but you do use local_listener parameter.
this parameter prevents pmon from registering a <DB_NAME>_XPT.<DOMAIN_NAME> service in the listener.
Thread: 611575.993 Bug: 4632635
Probably all this will be fixed in 10.2.0.2Google+