I want to measure latency and Throughput of SMs.What do you guys think which open source/freeware tools that make you satisfied and easy to do the report for manager ??? 
There are a few of them out there - try Google. There are also a number of posts on here about this topic. Some have recommended Cactii (sp) or JFFNMS (Just For Fun NEtwork Management System). Lots of people also just use MRTG just fine.
Aaron