sgl-project/sglang · critical · Exception

Generate subcommand is not yet supported for model: {model_p

Error message

Generate subcommand is not yet supported for model: {model_path}

What it means

The float16 branch of deterministic_all_reduce only supports world sizes 2,4,6,8; other sizes hit the default case and throw.

Source

Thrown at python/sglang/cli/generate.py:31

        parser = argparse.ArgumentParser(description="SGLang Multimodal Generation")
        add_multimodal_gen_generate_args(parser)
        parser.parse_args(extra_argv)
        return

    model_path = get_model_path(extra_argv)
    is_diffusion_model = get_is_diffusion_model(model_path)
    if is_diffusion_model:
        from sglang.multimodal_gen.runtime.entrypoints.cli.generate import (
            add_multimodal_gen_generate_args,
            generate_cmd,
        )

        parser = argparse.ArgumentParser(description="SGLang Multimodal Generation")
        add_multimodal_gen_generate_args(parser)
        parsed_args, unknown_args = parser.parse_known_args(extra_argv)
        generate_cmd(parsed_args, unknown_args)
    else:
        raise Exception(
            f"Generate subcommand is not yet supported for model: {model_path}"
        )

View on GitHub (pinned to 0132848349)

Solutions

1. Use an even TP size within 2-8
2. Disable the deterministic custom allreduce for unsupported topologies
3. Verify GPU visibility/env masks

assert fa.world_size_ in (2,4,6,8), 'deterministic fp16 allreduce needs TP in (2,4,6,8)'

When it happens

Trigger: Deterministic allreduce on fp16 tensors with fa->world_size_ outside {2,4,6,8}.

Common situations: --enable-deterministic-inference with TP=3/5/7 or >8 GPUs on ROCm; misdetected world size from bad visibility masks.

Related errors

• This browser does not support worker image decoding
• Unsupported content type ${header.content_type}
• Error: --model-type requires a non-empty value.
• delta payload size mismatch: expected ${expectedSize}, got $
• Missing previous frame for delta payload

AI-assisted analysis of sgl-project/sglang@0132848349 (2026-08-28). Data as JSON: /api/errors/cba447a574f990a3. Report an issue: GitHub.