The best way for root analysis is to use monitoring tools like dynatrace, sitescope, perfmon, nmon, introscope, sysload... With the help of these tools we can drill drown the issue and pin point the exact reason of performance degradation...
HI,Ravi ranjan Bro,,my notice period is started,,,so plz let me know (through my outlook ID ajjendrrakumar1@outlook.com)...if u know any queries in performance testing....