sgl-project/sglang · error · ValueError

min_hits must be positive, got {min_hits}

Error message

min_hits must be positive, got {min_hits}

What it means

The Kimi-K3 ViT CUDA graph runner's min_hits threshold (how many times a shape must be seen before capturing a graph) must be positive; min_hits <= 0 is rejected in __init__ to avoid capturing graphs for transient shapes.

Source

Thrown at python/sglang/srt/multimodal/kimi_k3_vit_cuda_graph_runner.py:48

    graph: torch.cuda.CUDAGraph
    input_buffer: torch.Tensor
    outputs: Tuple[torch.Tensor, ...]
    metadata: KimiK3VisionForwardMetadata


class KimiK3ViTCudaGraphRunner:
    def __init__(
        self,
        tower: KimiK3VisionTower,
        *,
        capacity: int,
        min_hits: int,
        max_seqlen: int | None = None,
    ) -> None:
        if capacity <= 0:
            raise ValueError(f"capacity must be positive, got {capacity}")
        if min_hits <= 0:
            raise ValueError(f"min_hits must be positive, got {min_hits}")
        if max_seqlen is not None and max_seqlen <= 0:
            raise ValueError(f"max_seqlen must be positive, got {max_seqlen}")
        self.tower = tower
        self.capacity = capacity
        self.min_hits = min_hits
        self.max_seqlen = max_seqlen
        self.graphs: dict[Hashable, _CapturedVisionGraph] = {}
        self.seen: OrderedDict[Hashable, int] = OrderedDict()
        self.failed_keys: set[Hashable] = set()
        self._graph_memory_pool: Any = None
        self._capacity_logged = False
        self._max_seqlen_logged = False
        logger.info(
            "Kimi-K3 ViT CUDA graph: capacity=%d min_hits=%d max_seqlen=%s",
            capacity,
            min_hits,
            max_seqlen,
        )

View on GitHub (pinned to 0132848349)

Solutions

1. Set min_hits >= 1 (2-3 is typical to avoid one-off captures)
2. Validate/normalize the value at config-parse time: max(1, min_hits)
3. Check the env var actually exporting the intended number

Example fix

// before
runner = KimiK3VitCudaGraphRunner(tower=t, capacity=8, min_hits=cfg.min_hits)  # cfg.min_hits == 0
// after
runner = KimiK3VitCudaGraphRunner(tower=t, capacity=8, min_hits=max(1, cfg.min_hits))

assert isinstance(min_hits, int) and min_hits >= 1, f"min_hits must be >= 1, got {min_hits}"

When it happens

Trigger: Constructing the runner with min_hits=0 or negative, e.g. from a default of 0 in a config struct or an env var parsed as int('0').

Common situations: Tuning scripts sweeping min_hits from 0; misparsed SGLANG_* env variable yielding 0.

Understand the failure class

Background: "Must be a positive integer", "Invalid value", "Unsupported": the invalid-argument-value error family, when a library rejects the value you pass — this error's family across 35 libraries.

Related errors

• capacity must be positive, got {capacity}
• max_seqlen must be positive, got {max_seqlen}
• --bcg-text-buckets must contain at least one positive intege
• Not support pos_emb_type: {pos_emb_type}
• Not support norm_type: {norm_type}

AI-assisted analysis of sgl-project/sglang@0132848349 (2026-08-28). Data as JSON: /api/errors/19d734bc432c6e3d. Report an issue: GitHub.