Use a MergeSorter taking advantage of extra storage for StableMSBRadixSorter #12623
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jpountz
approved these changes
Oct 5, 2023
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| private void merge(int from, int to, int mid) { | ||
| assert to > mid && mid > from; |
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In merge sort, it is common to check if the value at mid-1 is less than or equal to the value at mid, to save work in case the data is already (partially) sorted, maybe we could do that here too?
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Great advice! Thank you!
jpountz
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Oct 5, 2023
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Description
As
StableMSBRadixSorteralways requires aO(n)extra memory. We can use aMergeSortertaking advantage of the extra memory instead ofInPlaceMergeSorter.Benchmark
This reduces around 12% took of sorting ~10,000,000 timestamp values (LongPoint) during indexing.