Poor system response

We are on env 9.0.0.8. At times we notice that the system response becomes poor. 1) Any link under Employee Self Service link takes unreasonably long to present data (example pay checks). 2) Launching a screen in LID also takes longer than usual.

What does one look for in such cases ? We noticed that during such times "db2sysc" (related to Tivoli) process shows very high cpu utilization. I would appreciate if someone throws light on this process and also any other area to look at.

Thanks.