I am doing profiling of a Qt-based application in Windows10 using Intel VTune Amplifier 2019 (Update 8).
The problem is that the apllication stops to react and to respond when profiling is on.
The profiler is run paused and then resumed at the particular operation to be tested.
After resuming the application does not react and the operation stops at some stage (say 50%) and does not finish, but in Task Manager the application loads CPU quite extensively (i.e. something happens).
Without profiling, the operation goes well. The same problem happens under the same conditions but on another machine.
Could you recommend something what can help?
Thank you in advance.
Thank you for posting in Intel Forum.
Could you please share the application that you are profiling , so that we can try to reproduce the issue from our end. Also, let us know the type of analysis that you are trying to execute using VTune .
thank you very much for the feedback. Excuse me, I can't provide you the code... I can only say that it is a large program, and I test one of its multiple functionalities, which are tested daily. That's why the profiler is paused until I do all necessary actions before the particular operation beintg tested.
I perform the Hotspot analysis by collecting CPU sampling data with stacks and the 5ms interval. All the other options are set by default.
By summarizing, the operation works well without profiler. If it runs with Amplifier, it does not complete, stops at some point and does not respond. This does not depend on input file. All other known operations were tested well.
Maybe you can assume, why the profiler "blocks" the application and/or why there is a strange interaction? What can be the reason?
For example, I can speculate, it is due to the access permissions (hardly), memory (it should be enough), etc.
Could you tell me, if it is possible to see where the application stops by performing a kind of debugging while profiling? Maybe I could play with different options related to the hotspot analysis.
Thank you in adveance.
Thanks for the reply, no, I can't, I am applying what is provided.
Could you recommend some kind of analysis or a method to identify and find a location in the code where the profile gets stuck? How to find the reason?
Thanks for the response.
Make sure that VTune self check script is running fine to validate that appropriate drivers are installed and the system is set up properly to collect performance data.
On windows :
See whether its working fine and share the log.
Also, could you please attach the entire result folder so that we can debug the issue correctly.
Thank you very much for your reply and for the advice.
Unfortunately I can't find the file, but the idea is nice, it can show some diagnostic information.
Actually the file is not a problem, because it is just a command call, as far as I understand.
Could you tell me where I can download this file or what the command does check?
As for data of the performance results, I need to clarify this question.
The self-check file for windows “vtune-self-checker.bat” file will be there in the <vtune-installation-directory>/bin64 or <vtune-installation-directory>/bin32 folder if the VTune installation was done successfully. Or check for “amplxe-self-checker.bat “ .It is not possible to explicitly download the same.
· A self-check script is available to validate that appropriate drivers are installed and the system is set up properly to collect performance data
· The script runs several analysis types on a sample. After the script completes, it produces a log file and gives diagnostics on the success or failure of the checks.
· Finds possible collection limitations, missing permissions or outdated drivers and lists steps to overcome the limitations.
If you couldn’t find the self-checker script , then try profiling sample matrix app in the folder <vtune-installation-directory>\samples\en\C++\matrix and see whether you are able to get the results in VTune successfully.
Also, Please share the following details for better understanding of the issue.
a) After configuring the analysis in GUI , use Command Line Generator ( bottom right corner button) to generate CLI for the configuration you have made and share the same.( Refer attached Image1)
b) The result directory generated or the screenshot of collection log.
Thank you very much for the information and for the advice.
Excuse me for the delayed reply, it took some time to gether something to be reported, although I can't provide for now all the extensive information you required.
Meanwhile, the second operation was found with a similar effect while performing profile: the operation does not complete and the application stops to respond after some step while profiling. And this is very strange and a kind of restriction, the operation is successfully performed without profiling.
Nevertheless, the amplifier is an important tool, and I will try to complete carefully what you suggested to be sure that it works correct.
For now I can say definitely that I do not have the bat-files you wrote about: neither vtune-self-checker.bat, nor amplxe-self-checker.bat.
Could you provide the content of the file which you have as an example so that I have at least an overview what is done there? This is just a script, it should not be difficult.
Thank you for your patience. We installed the exact version of VTune you are using and tried to profile sample matrix application and we got the result successfully. We observed that the self-check file that we were talking about is not present in VTune 2019 update 8 folder and we apologize for asking you to check the same.
Could you please try upgrading to a latest version or we might need reproducer code or result folder for further debugging as we were able to profile samples.