Systemtap is a greatest tool for performance measurement, I ever found in Redhat distribution of Linux. When I started to use it , I felt like I got a tool to get full control over my Linux box. The theory behind Systemtap is getting complete detail of what going inside . Let’s assume you facing performance issue with your NFS server and your tried every settings to improve the performance . Since you are not aware what causing bottleneck of NFS server , so whatever settings you trying , it may just be a permutation/combination to improve the performance.
I think you would be interested in using this probing tool. To use tjis probing tool you have to install a few packages on your LInux box. To use Systemtap I installed following kernel packages
And obviosly following systemtap packages