topic Re: Vtune seems get wrong result profiling my program in Analyzers

Vtune seems get wrong result profiling my program

TCJ — Tue, 13 Jul 2021 07:46:08 GMT

when I profiling my program without `-qopenmp`, it works properly. But when I use it, the elapsed Time become extremely low and wrong. However, when I use CUI to profile the same openMP program, it works properly.

the Analysis Configuration and Collection Log does not offer any warnings.

Re:Vtune seems get wrong result profiling my program

AlekhyaV_Intel — Wed, 14 Jul 2021 12:00:43 GMT

Hi,

Thank you for posting in Intel Forums. We need the exact steps to reproduce so that we can debug further. Please provide the details of the OpenMP project you're currently working on. Also please provide us your VTune Profiler version and system information(OS & version)

Regards,

Alekhya

Re: Vtune seems get wrong result profiling my program

Bernard — Wed, 14 Jul 2021 17:07:07 GMT

"Elapsed Time" count seems to be small. You may be advised to increase the workload. The sampling mode incurres and overhead and for very short program (less than milisecond) the results may be skewed.

What is the average workload of your program?

Re:Vtune seems get wrong result profiling my program

AlekhyaV_Intel — Fri, 23 Jul 2021 10:02:06 GMT

Hi,

Could you please give us an update regarding this issue?

Regards,

Alekhya

Re: Re:Vtune seems get wrong result profiling my program

TCJ — Sun, 25 Jul 2021 06:59:56 GMT

sorry for being late, the notice email has been put into trash box automatically.

for the openMP project information :

we are optimizing it recently, and using vTune to profile. It's a image processing program which execution time has been optimized to 430ms.

recently, we have used vTune on other project, which occur the same problem while profiling multi thread omp program.(which has a longer executing time about 20seconds )

Vtune version and sys info :

host: windows 10 (windows 11 is the same) Intel oneAPI vTune Profier 2021.5.0

remote: ubuntu 18.04 Intel oneAPI vTune Profier 2021.5.0

Also:

due to the problem in remote profiling, we use Xmanager transfer remote GUI to local, and it work properly. So this problem seems only happen using remote ssh profile.

we also notice that the remote ssh profile could not automatically trace the source code of the profiling program (used -g flag when compiling )

Re: Re:Vtune seems get wrong result profiling my program

TCJ — Sun, 25 Jul 2021 07:01:50 GMT

I also tried advanced option duration time but the problem still.

Re: Vtune seems get wrong result profiling my program

TCJ — Sun, 25 Jul 2021 07:03:24 GMT

the duration of the program is about 480ms, but we also tested a 20seconds program. the problem repeat.

Re: Vtune seems get wrong result profiling my program

Bernard — Mon, 26 Jul 2021 13:49:12 GMT

@TCJ

You may try to minimize the overhead by creating a custom analysis for a single [architectural] performance events e.g. CPU_CLK_UNHALTED.THREAD. Set the "sample after value" to 2000003 and enable only counting of user mode counter overflow code triggers. Disable any stack collection option.

Re: Vtune seems get wrong result profiling my program

Dmitry_P_Intel1 — Mon, 26 Jul 2021 14:28:58 GMT

Hello,

It looks like the application that is run through VTune remote flow could not load OpenMP runtime. If so - one option is to create a wrapper script on the target that sources needed vars etc. and then invokes the application. And put this wrapper script as an application to launch for VTune remote collection.

Thanks & Regards, Dmitry

Re: Vtune seems get wrong result profiling my program

TCJ — Tue, 27 Jul 2021 04:44:23 GMT

did you mean .sh script, we have used it but that seems doesn't work

Re: Vtune seems get wrong result profiling my program

Dmitry_P_Intel1 — Tue, 27 Jul 2021 11:53:53 GMT

Hello, yes, I meant a kind of .sh script. Could you please redirect the output from the application run inside the script to a file and provide the output if it emitted by the app? It still looks like something was wrong at application startup.

Thanks & Regards, Dmitry

Re: Vtune seems get wrong result profiling my program

TCJ — Tue, 27 Jul 2021 13:32:33 GMT

thank, you for your reply.

there are some reason I can't provide the output file, but I checked whether the app start up properly.
And yes, the application not start up, but vtune launched .

Re: Vtune seems get wrong result profiling my program

TCJ — Tue, 27 Jul 2021 13:35:20 GMT

and the amplex-python on host doesn't output anything.

It used to display properly if the profile perform correctly

Re: Vtune seems get wrong result profiling my program

Dmitry_P_Intel1 — Tue, 27 Jul 2021 14:44:48 GMT

Acknowledging that VTune remote flow has limitation on propagating stferr from a target app to be displayed on a host. Have you been able to figure out the reason of the app startup issue and get it working through VTune remote flow?

Thanks & Regards, Dmitry

Re: Vtune seems get wrong result profiling my program

TCJ — Wed, 28 Jul 2021 09:41:40 GMT

not yet, I am complete confuse about this ORZ.

Re:Vtune seems get wrong result profiling my program

AlekhyaV_Intel — Wed, 04 Aug 2021 03:48:52 GMT

Hi,

Could you please provide us VTune result directory & self-checker logs so that we can debug your issue further.

Regards,

Alekhya

Re: Vtune seems get wrong result profiling my program

侯玉山 — Thu, 05 Aug 2021 07:43:29 GMT

I think，

it's because your program didn't run successfully. You can paste the execution command from VTune GUI to the command line to see whether the output prompt program runs successfully.

Re:Vtune seems get wrong result profiling my program

AlekhyaV_Intel — Wed, 11 Aug 2021 11:39:20 GMT

Hi,

Could you please give us an update regarding this issue? Please send us your VTune Result folder and self checker logs to work on your issue.

Regards,

Alekhya

Re:Vtune seems get wrong result profiling my program

AlekhyaV_Intel — Wed, 18 Aug 2021 06:55:10 GMT

Hi,

We have not heard back from you, So we'll close this inquiry now. If you need any further assistance, please post a new question as this thread will no longer be monitored.

Regards,

Alekhya