navision 3.60 session monitor

Hi! I don’t exactly understand the following fields shown in session monitor : records scanned, found/scanned ratio %, disk reads, disk writes, cache hit ratio%. who can me give some ideas. Also I want see which of my 80 users is using very hard my navision server. which fields are there for me most interesting? Thanks!

There were some description about this in the Performance Troubleshooting guide. Trye to search for tips in there.