tustvold opened a new issue, #2871:
URL: https://github.com/apache/arrow-rs/issues/2871

   **Is your feature request related to a problem or challenge? Please describe 
what you are trying to do.**
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   `lexsort`, `lexsort_to_indices`, `lexicographical_partition_ranges`, etc... 
make use of `LexicographicalComparator` to compare rows. The branching and 
dynamic dispatch involved in this comparator is relatively expensive. 
Converting to the row format first, and comparing these rows has been found to 
offer significant performance advantages in similar applications - 
https://github.com/apache/arrow-datafusion/pull/3386.
   
   **Describe the solution you'd like**
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   We should provide examples, and potentially some utilities if necessary, to 
use the row format for these use-cases instead. We can then deprecate the 
lexicographic kernels and eventually remove them
   
   **Describe alternatives you've considered**
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   We could leverage the row format within the existing kernels, however, this 
has a few drawbacks:
   
   * The additional memory consumption is not necessarily obvious
   * When chaining operators together, e.g. sort then partition, the row format 
conversion will be performed twice
   * It isn't obvious how process data in batches
   
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