[SunHELP] Performance Tuning

[sunhelp at sunhelp.org]

Hi,
I have a Oracle DB running in sun4u
the performance is very bad  so i thought may be increasing its SGA will
improve it so i tried to
increase my SGA but even though i raise  but i didnt get any performance
gain . so
it seems to me that may be the System needs tuning . so Will any body pls
let me know
How shall i   diagnose  to know that this system needs tuning

Thnx in advance
NP