OpenCL Crashes (SEGFAULT)

Problem

Zivid SDK crashes or behaves unstably in environments with multiple OpenCL platforms. A common pattern is that a CPU OpenCL platform is selected unintentionally instead of a supported GPU platform.

Note

CPU is an unsupported compute device mode in Zivid.

Possible cause

A mixed-platform setup contains both GPU and CPU OpenCL platforms, for example:

  • Intel GPU OpenCL platform

  • CPU OpenCL platform from another Installable Client Driver (ICD) provider

When ComputeDevice is explicitly pinned to CPU, this can cause unstable behavior, including crashes.

Solution

Unintentional CPU usage

Preferred resolution when CPU usage is not intentional.

  1. List OpenCL platforms and devices:

    1. Download the clinfo Windows binary file.

    2. Launch the Command Prompt by pressing Win + R keys on the keyboard, then type cmd and press Enter.

    3. Navigate to the directory that contains the downloaded file (clinfo.exe) and execute the following command:

      clinfo.exe -l

    1. Open a terminal window by pressing Ctrl + Alt + T keys on the keyboard and install clinfo.

      sudo apt install -y clinfo

    2. Run clinfo -l to list all OpenCL platforms.

      clinfo -l

  2. Verify whether CPU platforms are present and whether they might take precedence in your setup.

  3. Inspect your Configuration file and check ComputeDevice values.

  4. If CPU usage is not intentional, pin Zivid to a supported GPU in Configuration file:

    __version__:
    serializer: 1
    data: 19
Configuration:
    ComputeDevice:
        Type: GPU
        Vendor: Intel

    Use Vendor: NVIDIA if that is your intended GPU.

  5. Remove or disable conflicting CPU ICDs where appropriate for your environment.

  6. Re-run clinfo -l and verify that the resulting platform/device setup matches your intended configuration.

Intentional CPU usage

If CPU usage is intentional (unsupported mode), make this explicit by setting the compute device Type, Vendor, and AllowUnsupported.

__version__:
    serializer: 1
    data: 19
Configuration:
    ComputeDevice:
        Type: CPU
        Vendor: Intel
        AllowUnsupported: yes

Warning

CPU is an unsupported compute device mode. Capture time will be greatly increased when using CPU and this setup is not recommended for most applications. In mixed OpenCL platform setups, CPU selection can also cause unstable behavior, including crashes.