Assertion failed: find_pyobject_offsets when running Hotspot or Threading analysis

[deadpin]

A freshly downloaded 2023.1 version of vTune exhibits the following assertion on 2 different devices I've tried:

Assertion failed: find_pyobject_offsets:50: 0 : Offset of field of struct was not found (frame.f_lasti). Please contact the technical support.

The initial "Performance Snapshot" works fine. However, none of the other analysis types after that seem to.

Device 1:

Win10 22H2

Intel(R) Core(TM) i7-8750H CPU @ 2.20GHz

Device 2:

Win11 22H2

Intel(R) Xeon(R) Platinum 8370C CPU @2.80GHz

[JyothisV_Intel]

Hi,

Good day to you.

Thanks for posting in Intel Communities.

Kindly get back to us with the following information to assist you better:

1. A sample reproducer code or binary that you were analyzing using Intel VTune Profiler

2. The exact steps or guide that you followed to perform the analysis. Kindly make sure that you are running Intel VTune Profiler as administrator while performing Hotspot and Threading analysis.

3. Output of the VTune self-checker to see if VTune is installed and configured properly. This can be obtained by running the following instructions

a. Open a Command Prompt window with administrator privileges

b. Run the command "C:\Program Files (x86)\Intel\oneAPI\setvars.bat" (including quotes) to initialize the oneAPI environment variables

c. Run the command "C:\Program Files (x86)\Intel\oneAPI\vtune\latest\bin64\vtune-self-checker.bat" (including quotes) to run the VTune self-checker

d. Share the output of the self-checker with us

4. It would also be helpful if you could try running the same analysis on the official sample that is provided by Intel VTune. This is located in the directory:

C:\Users\<username>\Documents\VTune\Samples\matrix\matrix.exe

Try profiling the above executable and confirm if you are facing the same issue for hotspot and threading analysis with that sample. (Refer screenshot)

Regards,

Jyothis V James

[deadpin]

Any thoughts on my provided data?

[deadpin]

1. That will be difficult as it's a large open source application: Blender 3D.  I've compiled it using vs2022 17.4.3 and it runs fine otherwise.

2. I've configured analysis simply by providing the path to the executable.  The initial "Performance Snapshot" run is fine.  After "Performance Snapshot" finishes, I then select the "Hotspot" analysis type and that fails with the error when running.

3. Result file attached as log.txt.  The report itself says the following at the end

```

The system is ready for the following analyses:
* Performance Snapshot
* Hotspots and Threading with user-mode sampling
* Hotspots with HW event-based sampling, HPC Performance Characterization, etc.
* Microarchitecture Exploration
* Hotspots with HW event-based sampling and call stacks
* Threading with HW event-based sampling

The following analyses have failed on the system:
* Memory Access
* GPU Compute/Media Hotspots (characterization mode)
* GPU Compute/Media Hotspots (source analysis mode)

```

4. Hotspot and Threading both work fine on the "matrix" sample project

Is there additional logging I can enable to see why Blender is failing?

[JyothisV_Intel]

Hi,

Good day to you.

Thanks for getting back to us with detailed information.

We can confirm from the logs that the matrix sample works fine when profiled using Intel VTune Profiler.

Can you share the exact steps or guide that you followed to compile the application using vs2022 17.4.3 so that we can try reproducing it from our side. Also, kindly confirm if you are running VTune as administrator while performing the profiling.

Regards,

Jyothis V James

[deadpin]

Yes, this fails even when running as Administrator.

The documentation to follow to build Blender is here: https://wiki.blender.org/wiki/Building_Blender/Windows

It's relatively straightforward but would still be a long process the first time through.

[JyothisV_Intel · Accepted solution]

Hi,

Good day to you.

Sorry for the delay in getting back to you.

Thanks for providing the detailed steps for reproducing the issue. We tried compiling Blender for Windows using a machine with the following configuration and were able to replicate the issue from our side.

CPU: Intel(R) Core(TM) i7-8665U CPU @ 1.90GHz  2.11 GHz

OS: Windows 10 Enterprise 22H2 19045.3086

Visual Studio: 2022 Professional (17.5.2)

Error Screenshot:

Kindly try using hardware event-based sampling while performing the analysis. Use the checkbox Hardware Event-Based Sampling/Hardware Event-Based Sampling and/or Context Switches to resolve this issue while performing Hotspot/Threading or any other kind of analysis.

Hardware Event-Based Sampling should be used when the profiled application which collects the following information:

(Hotspots) Profiles shorter than a few seconds

(Hotspots/Threading) Profiling all processes on a system, including kernel

(Threading) Analyze applications that incur significant tracing overhead

(Threading) Measure an impact of thread preemption and context switching

See configuration panes for successful analysis here:

Hotspots Analysis:

Threading Analysis:

The successfully profiled screenshots are also attached for reference:

If this resolves your issues, kindly mark this as a solution as it will help others with a similar issue. If not, do get back to us so that we can assist you better.

Thanks and Regards,

Jyothis V James

[deadpin]

Yes, using Hardware event sampling seems to work.  This is a pretty bad user experience.  A better error message and logging would have prevented 15 days worth of effort to resolve...

[JyothisV_Intel]

Hi,

Good day to you.

We are extremely sorry that the user experience was not optimal. We have conveyed your feedback to the corresponding development team. Thanks for reporting the same. At this moment there is no visibility when it will be implemented.

Thanks and Regards,

Jyothis V James

[JyothisV_Intel]

Hi,

Good day to you.

We raised your concern with the development team who informed us that this was a known issue with User-Mode Sampling on older version of Intel VTune Profiler. This has been resolved on the latest Intel VTune Profiler version 2023.2.0.

Intel will no longer monitor this thread. If you need any assistance while using any Intel products or services, kindly post a new question.

Thanks and Regards,

Jyothis V James