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What resources exist for Database performance-tuning?
Can someone please suggest diagnostics steps for what caused oracle slow performance?
My application uses Oracle DB and it is cool most of the time, I sometime receive emails saying that application is extremely slow but by the time I login and check everything would be good.
I am wondering is there a way to check history (say some log file ) behind this performance issues.
If something is happening currently then I am aware to check locks (V$locks) etc.. But If I have to check what happened yesterday between 2 to 3:00PM while troubleshooting performance what should I look at?