Joined: 14 Mar 2007 Posts: 8657 Location: Back in jolly old England
is there any reason not to process the SMF data ??
since You are talking about SLA the ways of properly collecting data and provide the reports should not be unknown to Your support
Please read, and re read and re read Enricos previous reply. Especially the first line of his reply.
Now, just to save the possibility of joining the wheel reinvention society, have a chat with your performance / capacity planning people who will 95% of the time have already processed the SMF data using a proprietry package and almost certainly have the required information to hand within a few minutes.