Jun 20, 2025 · Apr 15, 2025 · Apr 16, 2025 · Apr 16, 2025 · Apr 16, 2025 · Apr 16, 2025
diff --git a/doc/release/upcoming_changes/28767.performance.rst b/doc/release/upcoming_changes/28767.performance.rst
 The hash-based algorithm for unique extraction provides
 an order-of-magnitude speedup on large string arrays.
 In an internal benchmark with about 1 billion string elements,
 the hash-based np.unique completed in roughly48 seconds,
 the hash-based np.unique completed in roughly34 seconds,
 compared to 498 seconds with the sort-based method
 – about10–11× faster for unsorted unique operations on strings.
 – about14–15× faster for unsorted unique operations on strings.
 This improvement greatly reduces the time to find unique values
 in very large string datasets.
Original file line number	Diff line number	Diff line change
Expand Up		@@ -3,8 +3,8 @@ Performance improvements to ``np.unique`` for string dtypes
		The hash-based algorithm for unique extraction provides
		an order-of-magnitude speedup on large string arrays.
		In an internal benchmark with about 1 billion string elements,
		the hash-based np.unique completed in roughly48 seconds,
		the hash-based np.unique completed in roughly34 seconds,
		compared to 498 seconds with the sort-based method
		– about10–11× faster for unsorted unique operations on strings.
		– about14–15× faster for unsorted unique operations on strings.
		This improvement greatly reduces the time to find unique values
		in very large string datasets.