Service Manager 7.11 Slow when escalating and creating an incident and closing the incident

I have a HPSM 7.11 server in our environment and  have a similar slowness issue while

1) creating interaction and escalating to incident for incident creation and incident creation takes more than a min

2) while closing the incident it is slow taking more than a minute or more to close.

But some times it will be normal 

What are the probable causes for this and how to fix this issue ? some one please help me