tustvold opened a new pull request, #2593:
URL: https://github.com/apache/arrow-rs/pull/2593
# Which issue does this PR close?
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Closes #.
# Rationale for this change
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I'm trying to improve the performance of the SortPreservingMerge operator in
DataFusion, and one of the major bottlenecks is performing multi-column
comparisons across `RecordBatch`. I started work on a JITed comparator, but not
only was this rather complicated and hard to validate, but the number of
unpredictable branches in the generated code made me unsure that the
performance would justify the complexity.
Taking a step-back with some bit-twiddling it is possible to construct a row
format that represents the values in a row in manner that can be compared with
`memcmp`. This will likely yield the fastest comparator possible, at the cost
of the time and memory overheads of assembling the row format.
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# Are there any user-facing changes?
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FYI @yjshen @alamb @crepererum
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