Improve KataGo performance on M2 Mac

[Sadaharu2624]

I just got a new M2 Mac recently and I tried running KataGo on it through Lizzie.
The good thing is it ran without changing any configurations from my Intel Mac.
However, I saw that the visits/s hovered at around 600~800 only.

Is there a way to improve the KataGo performance on my M2 Mac?
I'm using the OpenCL option.

I saw another thread about converting the KataGO to OpenML.
Is it faster than OpenCL?

[ChinChangYang]

Try this v1.13.2-coreml1 which implements the Core ML backend for KataGo.

Replace xcodebuild by xcodebuild -derivedDataPath DerivedData/KataGo if DerivedData is not found.

[taeuk-works]

Try this v1.13.2-coreml1 which implements the Core ML backend for KataGo.

Replace xcodebuild by xcodebuild -derivedDataPath DerivedData/KataGo if DerivedData is not found.

Do you have plan to merge your coreml implementation to main repository?

[ChinChangYang]

Metal, the GPU framework, is compatible with KataGo’s design, and I plan to merge the Metal backend into the main branch of KataGo. However, CoreML, which uses the ANE, is not compatible with KataGo’s design. Therefore, I don’t have any plans to merge the CoreML backend into the main branch.

[taeuk-works]

@ChinChangYang Then, may I expect your CoreML fork maintained in the future?

[ChinChangYang]

Yes. The latest update can be found in #865.

[taeuk-works]

@ChinChangYang Thanks for your works. hope that I can contribute your repo someday.

[milescrawford]

What's the status? This fork's instructions provide a huge gain on Mac over the mainline katago:
https://github.com/ChinChangYang/KataGo/blob/metal-coreml-stable/docs/CoreML_Backend.md

[ChinChangYang]

The latest status can be seen in #865. I believe this will never be merged into the main KataGo because the KataGo author doesn't seem to have an Mac to maintain the Metal and CoreML backends.

[milescrawford]

What? But surely one of the several dozen contributors do? Can't maintenance be contributed?

[ChinChangYang]

@lightvector would be the best person to answer this. If I were the author of KataGo, I’d likely focus on what could be learned from feedback and advancements. I appreciate the author’s responsibility in releasing a new version for Windows, though Mac isn’t currently the main focus.

[Sadaharu2624]

Hi @ChinChangYang I got this error when trying to compile using your branch. Any ideas?
I was doing this step and this happened in the last line.

ld: warning: ignoring file '/Users/macby-pro/KataGo-metal-coreml-stable/cpp/build/CMakeFiles/katago.dir/command/misc.cpp.o': found architecture 'arm64', required architecture 'x86_64'
Undefined symbols for architecture x86_64:
  "_main", referenced from:
      <initial-undefines>
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
ninja: build stopped: subcommand failed.
macby-pro@Mac-Studio build % 

[ChinChangYang]

The issue appears to be an architecture mismatch. Your toolchain is likely building for x86_64, but it should be targeting arm64.

Steps to Resolve

1. Clean the Build Directory

   • Remove the existing build artifacts to ensure no conflicts:

     rm -rf build
     mkdir build
     cd build

2. Verify Ninja Installation

   • Ensure that ninja is installed from Homebrew and configured correctly:

     which ninja

   • The output should be:

     /opt/homebrew/bin/ninja

3. Verify CMake Installation

   • Ensure that cmake is installed from Homebrew and configured correctly:

     which cmake

   • The output should be:

     /opt/homebrew/bin/cmake

This should figure out why the architecture mismatch and allow the build to complete successfully when the toolchain builds for arm64.

[Sadaharu2624]

@ChinChangYang

My results for which ninja and which cmake are these.
Is this the reason for the error?

/usr/local/bin/ninja

/usr/local/bin/cmake

[ChinChangYang]

To ensure everything is set up correctly, follow these steps:

1. Reinstall Ninja and CMake with Homebrew
   First, uninstall any existing versions of ninja and cmake, and then reinstall them via Homebrew to ensure compatibility with your system architecture:

   brew uninstall ninja cmake
   brew install ninja cmake

2. Add Homebrew's Path to Your Environment
   Append Homebrew's binary directory (/opt/homebrew/bin) to your PATH to ensure the correct versions of ninja and cmake are used:

   echo 'export PATH="/opt/homebrew/bin:$PATH"' >> ~/.zshrc

3. Apply the Updated Path
   Restart your terminal or reload your shell configuration to apply the changes immediately:

   source ~/.zshrc

After completing these steps, your environment should be configured correctly, and you’re ready to proceed with the build.