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sp-file-read-hot — measured, still hint

Status

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

Measurement

String(contentsOfFile:) of one one-byte file, 500 times, versus reading once.

rolecasemedian_msopsratio
afterread_once0.0145001
beforeread_each_iter5.819500413.669

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.