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pp-open-hot — measured, still hint

Status

hint. Wall-clock JSONL: pp-open-hot.jsonl. Not corpus-triaged. The 2026-10-22 corpus verdict does not cover this slug.

Measurement

Builtin open of one one-byte file, 2000 times, versus opening once.

rolecasemedian_msopsratio
afteropen_once0.04779220001
beforeopen_each_iter31.1697502000652.193

CPython 3.15.1, 2026-10-23. Warm 3, median of 9. The bench reopens one one-byte file.

The bench reopens one one-byte file. A path that changes every iteration cannot be hoisted; the measured cost is the open and read. Default stays hint. This ratio is not a general speedup.

Unblock

Do not set the default to error from this file alone. A changing input, a cold path, or another ABI can erase the difference. Corpus triage is still required before any default change.