Truncated time bar in "Thread Concurrency Histogram"

Truncated time bar in "Thread Concurrency Histogram"

Profiling with Intel® VTune Amplifier XE 2013, in the summary tab for concurrency analysis (as well as in Hotspots and Locks and Wait analysis) I see the time bars are truncated to 18 seconds. After disabling hyper threading and testing again, the bars are truncated to 9 seconds.  

Not sure how to fix this problem, I apprciate any help.

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Hi Ramin:

The bar height is not "truncated."  This is the amount of time spent in that level of concurrency.  For approximately 18 seconds you had 2 threads running concurrently.  For 18 seconds you had 5 threads running concurrently.  Does that make sense?

Dear MrAnderson, I forgot to mention why I am convinced it is truncated: 1- The elapsed time is 121.56 seconds, while adding the height of the bars in the above figure we'll notice it barely reaches  60 seconds. 2- The elapsed time after disabling hyperthreading remains more or less the same, but the time bars in the histogram are truncated to exactly 9.000 secs. The histogram does not look necessarily similar to the one with HT enabled, but the point is that there is no bars exceeding 9.000 seconds.

Thanks MrAnderson, that was a bug with VTune Amplifier. As per your suggestion I tried the latest update and the bug is fixed in Update 11.

Thanks for the update, Ramin!  Sorry for the inconvenience, but glad it is working now.

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