Intel VTune and system profiling

[pavlo_barvinko]

Dear VTune guru's,

Sorry beforehands for a long topic. I am currently evaluating whether we can use Intel VTune to perform system resource usage profiling. Our system consists of a number (up to 50) processes, running on a WinXP machine, having Intel CPU. We would like toprofile resource consumption of such a system, while it is performing a particular scenario. Under resource profiling I mean sampled (preferably every 1-10 ms) values of CPU usage (%, withdistribution per process). Also other resources will be monitored using Windows counters (memory, network and disk access), but CPU usage is of prime interest. I tried Intel VTune for this purpose and did not get (yet?)satisfactory results. Maybe I am using VTune in the way not it was designed for?

Nevertheless, here are my questions:

- For sampling data collection I set sampling frequency at 1 ms. However, when I would like to see profiled CPU usage in "Processes over time" view - the precision of a time bin is ~170 ms (number of columns is set to max 78 in options). Can it be viewed with original sampling period of 1 ms? Or can it be exported with such precision?

- In "Processes over time" view X-Axis is cut to 13 seconds, while original data collection has taken 20 seconds. Why? I have not found any way to shift it further to see interval between 13 and 20 sec.

- For time-based sampling in a "Processes over time" view I would expect that sum of all time ticks per process per one time bin (e.g. sum of every column) would give me the same result - e.g. kind of total CPU time ticks per bin. However it is not true with a huge difference (e.g. 186, 212, 340, 185, ...). Why? It is not the idle process, which is missing - it is on the list.

- Is it possible to synchronize data collection process (sampling) with some kind of system wide timer? (To the Windows performance counter, for example?) The reason for this question is that we would like to combine (put on the same time axis) traces from our applications, which use Windows performance counter, and data, produced duringVTune runs.

- Is it possible to synchronise data collection process (sampling) with some kind of external event? If the previous item is not possible then we would like to use this synchronisation mechanism to startdata collectionsynchronously with the start of scenario (preferably without VTune activity starting overhead)

Thank you very much in advance and sorry again for the long post.

[Intel_C_Intel]

To use VTune for system sampling, you will want to use Counter Monitor and Sampling together. Counter Monitor makes use of the Windows* Perfmon counters and then the sampling ties them together to allow view of source code. To do this follow these steps:

1. From the "Easy Start" dialog, choose New Project.

2. Select "Counter Monitor" Wizard and press "OK."

3. Check the "No Application to Launch" button and press "Next."

4. Check the bottom option,Typical Applicationand press "Next."

5. Choose the duration you want to run, then check the "Collect Sampling Data" checkbox and press "Finish."

The sampling run with then run with real-time counter data on the scree for as long as you entered. Upon completion of the run you will be presented with a dialog box to choose which run to view. Select "Counter Monitor Results."

Now you will see a graph display of the Perfmon counters, which you can then zoom in on and drill down to sampling data for the details during that particular time-period.

Press the Icon that looks like a graph (Select Range to Zoom/Drill Down) and then left-click and drag the region you want to view. Press the Magnifying Glass icon (Zoom) to zoom in on that view. When you are happy and ready to see the sampling data for that time-period, press the Drill Icon to "Drill Down" to the sampling view.

I hope that helps and enjoy VTune! :)