Learning Forum

[robertem2k]

Regarding potential GPU usage by HFSS simulation, Electronic Desktop Help documentations mentions, beside a couple of other conditions "...The times using CUDA and CPU only are estimated. If GPU is faster, it will be used. If not, the solver falls back to multi-core CPU...".    

Are the results of this particular test, during simulation run, logged in some file? 

I am trying to test if my HFFS antenna coupling simulations attempt to utilize Nvidia A100 GPU, or not, and if not what is the reason (to investigate how to take adavantage of available GPU).  I cannot seem to find this information in the log files.

In my simulation the reported (in HFSS->Results->Solutions Data) max matrix size varies (depending on the simulation model) from > 3,000,000 to > 16,000,000, and max used RAM 25GB, total number of cores: 24 (is it a number of cores available or actually used?). 

I would like to understand where could I find more detailed logged information how many CPU and GPU resources have been used after long simulation ends. 

Any suggestions?  TIA.

 

[Ronald Higgins]

To check whether your HFSS (High-Frequency Structure Simulator) simulations are utilizing the Nvidia A100 GPU, you can investigate several areas:

HFSS Log Files
HFSS typically generates log files that provide details about the simulation run. While these logs may not directly show whether a GPU is being used, they can give hints about the solver settings and performance metrics. Here’s how you can find and interpret these logs:

Simulation Log Files: Look for the .log files generated during the simulation run. These files are usually located in the project directory or in a subdirectory named after your simulation setup.

Solver Messages: Within the HFSS interface, go to the Message Manager (found under the "View" tab), which may include solver-specific messages about resource usage, including whether GPU acceleration was attempted or used.

Checking GPU Utilization
To directly check if your Nvidia A100 GPU is being used during the simulation, you can use Nvidia's tools:

nvidia-smi: This command-line tool provides detailed information about GPU usage, including memory usage and GPU utilization. Run this command in a terminal while the simulation is running:
nvidia-smi
Look for HFSS or related processes in the output, which would indicate GPU usage.
HFSS Settings and Configurations
Ensure that HFSS is configured to utilize GPU resources. Check the following settings in HFSS:

Solver Settings: In the HFSS project, go to Analysis Setup -> Solution Setup, and check the Advanced tab to ensure that GPU acceleration is enabled.

Maximize GPU Utilization: Ensure that your simulation model is compatible with GPU acceleration. Some HFSS solvers and features are not GPU-accelerated, and the software may fall back to CPU if certain conditions are not met.

Ansys Documentation and Support
The Electronic Desktop Help documentation and Ansys support may provide additional insights into GPU usage:

Documentation: Search for terms like "GPU acceleration", "CUDA", and "solver settings" in the HFSS documentation to find relevant sections.

Ansys Support: If the documentation and log files do not provide sufficient information, consider reaching out to Ansys support. They can provide specific guidance on how to ensure GPU utilization for your simulations.

Example Configuration
Here’s an example of how to enable GPU acceleration in HFSS:

Enable GPU Acceleration:

Open your HFSS project.
Go to Analysis Setup -> Solution Setup.
Click on the Advanced tab.
Ensure that Enable GPU Acceleration is checked.
Review and Run Simulation:

Start your simulation.
Monitor the nvidia-smi output to check if the GPU is being utilized.
Post-Simulation Analysis
After the simulation ends, you can review the log files and message manager for any indications of GPU usage:

Log Files: Check for lines mentioning CUDA or GPU.
Message Manager: Look for messages about solver performance and resource allocation.
By following these steps, you should be able to determine whether your HFSS simulations are utilizing the Nvidia A100 GPU and identify any potential issues preventing GPU usage. If you still face issues, consider seeking help from experts in custom software development, maybe they can help you https://tech-stack.com/