The onnxruntime thread usage is not playing well with our search threads, at least with onnx-cpu. Restricting each evaluation to a single thread seems to be a decent performance win for more that 2 search threads with onnxruntime 1.4.0, that uses threads more aggressively. Here I introduce a threads backend option that defaults to 1 for onnx-cpu and 0 (default) otherwise.
The onnxruntime thread usage is not playing well with our search threads, at least with onnx-cpu. Restricting each evaluation to a single thread seems to be a decent performance win for more that 2 search threads with onnxruntime 1.4.0, that uses threads more aggressively. Here I introduce a
threadsbackend option that defaults to 1 for onnx-cpu and 0 (default) otherwise.