As a DBA, I routinely check on three network-related areas: latency, collisions, and dropped packets. If there is a network issue, it is nearly always a latency issue. But in your career, you will undoubtedly encounter a collision issue and perhaps even a dropped packets problem.

If you suspect there is a latency issue, my first recommendation is to gets many, many samples. Network people can be extremely gruff. And if you crawled around on your hands and knees all day stringing cable, or spent hours staring at network graphs, you would probably be the same way.

Modern networks can be programmed to change packet routing based on packet type, time of day, and activity intensity. The only way to really understand latency issues is to take a lot of samples, paste them into Excel, and create a scatter graph.