My question concerns what I'm seeing in Windows Performance Monitor. I've created a performance counter in my C# app. It measures the average time it takes to perform an operation as I simulate adding users via threads.
As I watch the performance display in PerfMon, I see the vertical red line move across the screen in what appears to be one second increments. My question is this. Exactly what is it displaying as the line moves across the screen every one second? Am I seeing the current average of all values at that exact point in time, or am I seeing the average of values since the last update (one second ago)? What I'm seeing leads me believe it's the latter but I'm not sure.
The reason I think it's the latter is because I sometimes see the average fall to zero (briefly). This simply couldn't be if it were showing the average of all values since I started my app.
You can create collector sets with different sampling rates. Different counters represent different values -- one might be a total value, another might be a per-second frequency value. Most counters also display current/last/average/max readings numerically when you click on the individual counter in PerfMon.