Async: stop re-copying input on every hash loop #15967
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prestonvanloon
previously requested changes
Nov 3, 2025
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prestonvanloon
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prestonvanloon
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This fundamentally changes the behavior of the test.
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Closing this since it changes the behavior significantly without a basis for doing so. The data was changed on each iteration when the hash was done and this is not identical behavior. |
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Re-reading it, and I believe I was mistaken since the inner loop is not hashing all of the inputs each iteration. |
prestonvanloon
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their stale review
No explicit request any more. I'm not sure we need this, but I do not want to block it
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Summary: Move the copy(output, input) out of the per-element loop in hash, so the benchmark keeps identical behavior while avoiding O(n²) copies. Why: Each iteration previously copied the entire slice even though the data was unchanged. One upfront copy preserves semantics and eliminates redundant work. Testing: go test ./async/... (cannot run here: Go toolchain missing in environment)