bpo-37029: keep usable_arenas in sorted order without searching #13612
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sorted by number of free pools.
methane
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May 29, 2019
methane
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May 31, 2019
pitrou
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May 31, 2019
| @@ -1172,6 +1189,9 @@ static struct arena_object* unused_arena_objects = NULL; | |||
| */ | |||
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Add comment documenting that they are sorted in number of free pools?
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I'd rather not, unless you feel strongly about it. This has been documented all along, but up where the main explanation of arenas lives (look at the comment block about usable_arenas at line 1150).
There are a bunch of moving parts here, and the style of the file is to give long-ish English explanations in uninterrupted comment blocks, with only the briefest of memory-jogging comments on declaration lines.
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@tim-one: Please replace |
DinoV
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Jan 14, 2020
…on#13612) This adds a vector of "search fingers" so that usable_arenas can be kept in sorted order (by number of free pools) via constant-time operations instead of linear search. This should reduce worst-case time for reclaiming a great many objects from O(A**2) to O(A), where A is the number of arenas. See bpo-37029.
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This adds a vector of "search fingers" so that usable_arenas can be kept in sorted order (by number of free pools) via constant-time operations instead of linear search.
This should reduce worst-case time for reclaiming a great many objects from O(A**2) to O(A), where A is the number of arenas.
https://bugs.python.org/issue37029