vTune Sampling Results scattered in multiple rows -- for my single core application

[k_sarnath]

Hi,

I am trying to profile a single core application (matrix kindaa 2D operation..).

I tried sample profiling with 11 events. When I drill down into my EXE in the sampling results, the window shows 4 threads and data are scaterred between these rows.. Howver, my application is only single-threaded. To reduce confusion, I also nail my main thread to 1 core using the following call:

SetThreadAffinityMask(GetCurrentThread(), 1);

Since the data is scattered in 4 rows now, certain ratios are not coming out clearly. For example: DTLB_MISSES.ANY and INST_RETIRED.ANY are seen in different rows and hence DTLB Miss Rate is 0 in all the 4 rows... I had to divide the data from 2 different rows to make sure that I get the correct rate...

How do I get past this?

Also, what is the "%" of various events shown in the sampling results? They are all 100% always....May be, if I drill down further there would be variations.... Ha.. Possibly...

Thanks for your time,

Best Regards,

Sarnath

[David_A_Intel1 · Accepted solution]

Yeah, this is simply a result of having to run your single-threaded application multiple times to collect all the events, since the processor only supports collecting N events at a time.

The trick is to skip the thread view. To do this, from the process view, click on the Modules button:



Which will give you the module-level data with the ratios:



Let me know if that helps.

[k_sarnath]

This looks like a good idea... I was always wondering how togo-up after I drill-down..... Looks like, "Modules" is the key..... Right?
Is there any other way to drill-upward like a stack(for a lack of better word) after I drill-down..

Thanks! (I was expecting the forum to notify me of replies... I had subscribed to this thread.. Sadly that does not work..)

[David_A_Intel1]

Likewise, I expected to be notified of your reply, but the special mechanism for us is not working, either. :-(

To answer your question, though, you may notice the tabs at the bottom of the display. You can use these to jump "back" to where you drilled down from:

[k_sarnath]

Vow! That was useful! Thank you very much Mr.Anderson!