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perf: optimize array_remove for scalar needle#22390

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lyne7-sc:perf/remove
Open

perf: optimize array_remove for scalar needle#22390
lyne7-sc wants to merge 4 commits into
apache:mainfrom
lyne7-sc:perf/remove

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Which issue does this PR close?

  • Closes #.

Rationale for this change

Similar to #22387 (array_replace scalar optimization)

array_remove / array_remove_n / array_remove_all perform element-wise comparison by invoking compare_element_to_list against each row's sub-array individually. When the needle is a scalar, this can be optimized by performing a single vectorized distinct comparison over the entire flattened values buffer.

What changes are included in this PR?

  • Add a specialized removal kernel (general_remove_with_scalar) that uses arrow_ord::cmp::distinct with Scalar wrapper for a single bulk comparison pass over the flat values buffer.
  • Extend SLT tests with multi-row scalar-argument coverage, NULL-containing arrays, empty-array edge cases, boundary n values, and LargeList type coverage.

Benchmarks

group                                                                    baseline                               optimized
-----                                                                    --------                               ---------
array_remove_all_int64/remove/list size: 10, num_rows: 4000              4.10   853.8±25.65µs        ? ?/sec    1.00    208.4±2.94µs        ? ?/sec
array_remove_all_int64/remove/list size: 100, num_rows: 10000            1.41      5.6±0.26ms        ? ?/sec    1.00      4.0±0.64ms        ? ?/sec
array_remove_all_int64/remove/list size: 500, num_rows: 10000            1.06     18.9±0.43ms        ? ?/sec    1.00     17.8±0.53ms        ? ?/sec
array_remove_all_int64_nested/remove/list size: 10, num_rows: 4000       1.00      7.0±0.26ms        ? ?/sec    1.03      7.2±0.59ms        ? ?/sec
array_remove_all_int64_nested/remove/list size: 100, num_rows: 3000      1.00     36.4±0.54ms        ? ?/sec    1.01     36.6±0.29ms        ? ?/sec
array_remove_all_int64_nested/remove/list size: 300, num_rows: 1500      1.00     52.6±0.95ms        ? ?/sec    1.01     53.0±1.17ms        ? ?/sec
array_remove_boolean/remove/list size: 10, num_rows: 4000                3.76  846.9±108.47µs        ? ?/sec    1.00    225.3±2.84µs        ? ?/sec
array_remove_boolean/remove/list size: 100, num_rows: 10000              2.06      4.1±0.79ms        ? ?/sec    1.00  1983.4±48.23µs        ? ?/sec
array_remove_boolean/remove/list size: 500, num_rows: 10000              1.62     11.0±1.50ms        ? ?/sec    1.00      6.8±0.08ms        ? ?/sec
array_remove_fixed_size_binary/remove/list size: 10, num_rows: 4000      3.12   933.9±76.49µs        ? ?/sec    1.00    299.2±4.95µs        ? ?/sec
array_remove_fixed_size_binary/remove/list size: 100, num_rows: 10000    1.51      7.5±0.41ms        ? ?/sec    1.00      5.0±0.10ms        ? ?/sec
array_remove_fixed_size_binary/remove/list size: 500, num_rows: 10000    1.19     30.1±3.18ms        ? ?/sec    1.00     25.4±0.89ms        ? ?/sec
array_remove_int64/remove/list size: 10, num_rows: 4000                  4.35   837.8±42.38µs        ? ?/sec    1.00    192.6±3.69µs        ? ?/sec
array_remove_int64/remove/list size: 100, num_rows: 10000                2.09      4.1±0.63ms        ? ?/sec    1.00  1947.7±341.88µs        ? ?/sec
array_remove_int64/remove/list size: 500, num_rows: 10000                1.15     10.9±0.83ms        ? ?/sec    1.00      9.5±3.14ms        ? ?/sec
array_remove_int64_nested/remove/list size: 10, num_rows: 4000           1.00      7.0±0.20ms        ? ?/sec    1.01      7.1±0.18ms        ? ?/sec
array_remove_int64_nested/remove/list size: 100, num_rows: 3000          1.00     36.0±0.92ms        ? ?/sec    1.00     36.0±0.38ms        ? ?/sec
array_remove_int64_nested/remove/list size: 300, num_rows: 1500          1.01     52.3±1.28ms        ? ?/sec    1.00     51.9±0.73ms        ? ?/sec
array_remove_n_int64/remove/list size: 10, num_rows: 4000                4.11   854.5±26.44µs        ? ?/sec    1.00    207.7±4.18µs        ? ?/sec
array_remove_n_int64/remove/list size: 100, num_rows: 10000              1.73      5.2±0.82ms        ? ?/sec    1.00      3.0±0.60ms        ? ?/sec
array_remove_n_int64/remove/list size: 500, num_rows: 10000              1.11     15.7±2.01ms        ? ?/sec    1.00     14.2±1.97ms        ? ?/sec
array_remove_n_int64_nested/remove/list size: 10, num_rows: 4000         1.03      7.2±0.56ms        ? ?/sec    1.00      7.0±0.08ms        ? ?/sec
array_remove_n_int64_nested/remove/list size: 100, num_rows: 3000        1.00     36.3±1.28ms        ? ?/sec    1.01     36.5±0.39ms        ? ?/sec
array_remove_n_int64_nested/remove/list size: 300, num_rows: 1500        1.00     51.4±0.59ms        ? ?/sec    1.01     51.8±0.54ms        ? ?/sec
array_remove_strings/remove/list size: 10, num_rows: 4000                2.48  1137.7±23.31µs        ? ?/sec    1.00   458.2±12.41µs        ? ?/sec
array_remove_strings/remove/list size: 100, num_rows: 10000              1.31     10.3±0.61ms        ? ?/sec    1.00      7.9±0.17ms        ? ?/sec
array_remove_strings/remove/list size: 500, num_rows: 10000              1.14     40.1±4.03ms        ? ?/sec    1.00     35.2±0.98ms        ? ?/sec

Are these changes tested?

Yes, existing and new SLT edge-case tests in array_remove.slt.

Are there any user-facing changes?

No.

@github-actions github-actions Bot added sqllogictest SQL Logic Tests (.slt) functions Changes to functions implementation labels May 20, 2026
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Nice performance win!

);
}
};
let original_data = list_array.values().to_data();
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This will be inefficient for sliced arrays.

let list_array = array.as_list::<i64>();
general_remove_with_scalar::<i64>(list_array, needle, arr_n)
}
array_type => exec_err!("array_remove does not support type '{array_type}'."),
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This is called by more than just array_remove; can we improve the error message?

Comment on lines +596 to +607
for (i, keep) in eq_array.iter().enumerate() {
if keep == Some(false) && removed < max_removals {
if let Some(bs) = pending_batch_to_retain {
mutable.extend(0, start + bs, start + i);
copied += i - bs;
pending_batch_to_retain = None;
}
removed += 1;
} else if pending_batch_to_retain.is_none() {
pending_batch_to_retain = Some(i);
}
}
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I wonder if it would be possible to iterate only over the "false" bits, e.g., by negating the buffer and looking at BooleanBuffer::set_indices.

let mut copied = 0usize;
let mut pending_batch_to_retain: Option<usize> = None;
for (i, keep) in eq_array.iter().enumerate() {
if keep == Some(false) && removed < max_removals {
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Can we break from the loop once we hit max_removals?

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