[robert3005]

The file writer accumulated every column's stats twice: once into the nested aggregate stats tree and again into separate legacy top-level accumulators. Derive the legacy top-level stats from the nested tree instead, adding a LegacyOnly node for the own stats of non-nullable top-level struct fields, which only the legacy layout records.

[codspeed]

Merging this PR will improve performance by 10.6%

3 warnings, 1 note

⚠️ Walltime results may be unreliable

Some benchmarks used the Walltime instrument outside CodSpeed Macro Runners, which can make the results inconsistent.

Learn more about Macro Runners

See affected benchmarks

⚠️ Unable to measure the execution of 2 benchmarks

These benchmarks measured no execution time, so their results are not comparable and count as unchanged. This usually happens when the compiler removes the code under test.

Prevent compiler optimizations

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⚠️ 20 benchmarks are dominated by system calls

System calls cannot be simulated consistently and are left out of the measure. The reported value understates the real cost. Switch to the Walltime instrument to measure them.

Learn more about system calls

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ℹ️ 40 benchmarks have no flamegraph

The flamegraph wasn't generated: the symbols of the profiling trace could not be resolved, because no information about the language frames was collected.

See affected benchmarks

⚡ 1 improved benchmark
✅ 2438 untouched benchmarks
⏩ 12 skipped benchmarks¹

Performance Changes

	Mode	Benchmark	BASE	HEAD	Efficiency
⚡	Walltime	deferred_bool_avx512[i64, PerRowPerRow]	3.9 µs	3.6 µs	+10.6%

Tip

Curious why performance improved? Comment @codspeedbot explain why performance improved on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing rk/single-pass-file-stats (f5accc5) with develop (a59294e)}

Footnotes

1. 12 benchmarks were skipped, so the baseline results were used instead. If they were deleted from the codebase, click here and archive them to remove them from the performance reports. ↩