sgl-project/sglang · error · ValueError

Invalid global_segment_size: missing number before 'gb'

Error message

Invalid global_segment_size: missing number before 'gb'

What it means

Parsing global_segment_size rejected a string like 'gb' or ' gb' — the suffix was present but the numeric part was empty. The parser accepts ints, plain numeric strings, or '<N>gb' (converted to bytes).

Source

Thrown at python/sglang/srt/mem_cache/storage/mooncake_store/mooncake_store.py:78

        tensor = torch.frombuffer(c_array, dtype=torch.uint8, count=size)

        if dtype != torch.uint8:
            element_size = torch.tensor([], dtype=dtype).element_size()
            assert size % element_size == 0, "Size must be divisible by element size"
            tensor = tensor.view(dtype)

        return tensor.view(dims)


def _parse_global_segment_size(value) -> int:
    if isinstance(value, int):
        return value
    if isinstance(value, str):
        s = value.strip().lower()
        if s.endswith("gb"):
            num = s[:-2].strip()
            if not num:
                raise ValueError(
                    "Invalid global_segment_size: missing number before 'gb'"
                )
            return int(num) * 1024 * 1024 * 1024
        return int(s)
    return int(value)


def _normalize_tenant_id(value) -> str:
    if value is None:
        return DEFAULT_TENANT_ID
    tenant_id = str(value).strip()
    return tenant_id if tenant_id else DEFAULT_TENANT_ID


@dataclass
class MooncakeStoreConfig:
    local_hostname: str
    metadata_server: str

View on GitHub (pinned to 0132848349)

Solutions

1. Set a valid value: integer bytes or "<N>gb", e.g. "8gb" or 8589934592

Example fix

// before
{"global_segment_size": "gb"}
// after
{"global_segment_size": "8gb"}

import re
def valid_global_segment_size(v) -> bool:
    if isinstance(v, int):
        return v > 0
    if isinstance(v, str):
        s = v.strip().lower()
        if s.endswith('gb'):
            return bool(re.fullmatch(r'\d+(\.\d+)?', s[:-2].strip()))
        return s.isdigit()
    return False

When it happens

Trigger: Passing MooncakeStoreConfig global_segment_size as the literal string 'gb', 'GB', or whitespace-only before the suffix.

Common situations: Hand-edited mooncake config JSON with "global_segment_size": "gb" or a templating variable that expanded to empty.

Related errors

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AI-assisted analysis of sgl-project/sglang@0132848349 (2026-08-28). Data as JSON: /api/errors/4121a36928e546e8. Report an issue: GitHub.