Move benchmarks for querying on empty containers to the generic tests

arbiny · arbiny · commit 1de748745345 · 2025-05-08T15:23:38.000+08:00
For expensive key, such as std::unordered_set<std::string>, the benchmark reulst: 1. With the opt: ------------------------------------------------------------------------------------------------------------------------------------- Benchmark Time CPU Iterations ------------------------------------------------------------------------------------------------------------------------------------- std::unordered_set<int>::ctor(const&)/32 4717 ns 4718 ns 143456 std::unordered_set<int>::ctor(const&)/1024 160766 ns 160764 ns 4384 std::unordered_set<int>::ctor(const&)/8192 1362608 ns 1362523 ns 544 std::unordered_set<int>::ctor(iterator, iterator) (unsorted sequence)/32 6493 ns 6493 ns 104416 std::unordered_set<int>::ctor(iterator, iterator) (unsorted sequence)/1024 204541 ns 204539 ns 3456 std::unordered_set<int>::ctor(iterator, iterator) (unsorted sequence)/8192 1712671 ns 1712620 ns 416 std::unordered_set<int>::ctor(iterator, iterator) (sorted sequence)/32 6533 ns 6534 ns 107136 std::unordered_set<int>::ctor(iterator, iterator) (sorted sequence)/1024 202608 ns 202603 ns 3456 std::unordered_set<int>::ctor(iterator, iterator) (sorted sequence)/8192 1707584 ns 1707476 ns 416 std::unordered_set<int>::operator=(const&)/32 4814 ns 4814 ns 147424 std::unordered_set<int>::operator=(const&)/1024 154541 ns 154535 ns 4416 std::unordered_set<int>::operator=(const&)/8192 1310847 ns 1310769 ns 416 std::unordered_set<int>::insert(value) (already present)/32 57.5 ns 57.5 ns 12193408 std::unordered_set<int>::insert(value) (already present)/1024 60.4 ns 60.4 ns 11587808 std::unordered_set<int>::insert(value) (already present)/8192 60.7 ns 60.7 ns 9435360 std::unordered_set<int>::insert(value) (new value)/32 153 ns 154 ns 4433696 std::unordered_set<int>::insert(value) (new value)/1024 164 ns 164 ns 3980992 std::unordered_set<int>::insert(value) (new value)/8192 165 ns 165 ns 4045664 std::unordered_set<int>::insert(iterator, iterator) (all new keys)/32 6416 ns 6419 ns 102879 std::unordered_set<int>::insert(iterator, iterator) (all new keys)/1024 205733 ns 205748 ns 3425 std::unordered_set<int>::insert(iterator, iterator) (all new keys)/8192 1583461 ns 1583454 ns 443 std::unordered_set<int>::insert(iterator, iterator) (half new keys)/32 4363 ns 4370 ns 154592 std::unordered_set<int>::insert(iterator, iterator) (half new keys)/1024 141932 ns 141921 ns 5014 std::unordered_set<int>::insert(iterator, iterator) (half new keys)/8192 1096349 ns 1096330 ns 641 std::unordered_set<int>::erase(key) (existent)/32 149 ns 149 ns 4715776 std::unordered_set<int>::erase(key) (existent)/1024 153 ns 153 ns 4587936 std::unordered_set<int>::erase(key) (existent)/8192 157 ns 157 ns 3200000 std::unordered_set<int>::erase(key) (non-existent)/32 48.6 ns 48.6 ns 14433088 std::unordered_set<int>::erase(key) (non-existent)/1024 55.4 ns 55.4 ns 14368768 std::unordered_set<int>::erase(key) (non-existent)/8192 50.1 ns 50.0 ns 12491488 std::unordered_set<int>::erase(iterator)/32 106 ns 106 ns 6649824 std::unordered_set<int>::erase(iterator)/1024 108 ns 107 ns 6551744 std::unordered_set<int>::erase(iterator)/8192 108 ns 108 ns 6368928 std::unordered_set<int>::erase(iterator, iterator) (erase half the container)/32 1869 ns 1861 ns 373187 std::unordered_set<int>::erase(iterator, iterator) (erase half the container)/1024 50300 ns 50256 ns 13894 std::unordered_set<int>::erase(iterator, iterator) (erase half the container)/8192 410477 ns 410379 ns 1707 std::unordered_set<int>::clear()/32 1047 ns 1038 ns 672424 std::unordered_set<int>::clear()/1024 24126 ns 24090 ns 29056 std::unordered_set<int>::clear()/8192 188620 ns 188534 ns 3693 std::unordered_set<int>::find(key) (existent)/32 52.2 ns 52.2 ns 13406688 std::unordered_set<int>::find(key) (existent)/1024 48.4 ns 48.4 ns 13773728 std::unordered_set<int>::find(key) (existent)/8192 55.8 ns 55.8 ns 12571776 std::unordered_set<int>::find(key) (non-existent)/32 41.0 ns 41.0 ns 14667808 std::unordered_set<int>::find(key) (non-existent)/1024 43.5 ns 43.5 ns 16278688 std::unordered_set<int>::find(key) (non-existent)/8192 41.2 ns 41.2 ns 15790752 std::unordered_set<int>::find(key) (expensive-empty)/32 14.6 ns 14.6 ns 47838272 std::unordered_set<int>::find(key) (expensive-empty)/1024 14.6 ns 14.6 ns 47741568 std::unordered_set<int>::find(key) (expensive-empty)/8192 14.7 ns 14.7 ns 47780224 std::unordered_set<int>::count(key) (existent)/32 58.4 ns 58.4 ns 12129728 std::unordered_set<int>::count(key) (existent)/1024 57.4 ns 57.4 ns 12091968 std::unordered_set<int>::count(key) (existent)/8192 61.1 ns 61.1 ns 12053312 std::unordered_set<int>::count(key) (non-existent)/32 60.7 ns 60.7 ns 13021152 std::unordered_set<int>::count(key) (non-existent)/1024 57.1 ns 57.1 ns 12352160 std::unordered_set<int>::count(key) (non-existent)/8192 61.1 ns 61.1 ns 14251424 std::unordered_set<int>::count(key) (expensive-empty)/32 19.4 ns 19.4 ns 36120640 std::unordered_set<int>::count(key) (expensive-empty)/1024 19.4 ns 19.4 ns 36122336 std::unordered_set<int>::count(key) (expensive-empty)/8192 19.4 ns 19.4 ns 35992544 std::unordered_set<int>::contains(key) (existent)/32 57.7 ns 57.7 ns 11540576 std::unordered_set<int>::contains(key) (existent)/1024 56.1 ns 56.1 ns 11500288 std::unordered_set<int>::contains(key) (existent)/8192 60.5 ns 60.5 ns 11040832 std::unordered_set<int>::contains(key) (non-existent)/32 58.9 ns 58.9 ns 13091488 std::unordered_set<int>::contains(key) (non-existent)/1024 53.0 ns 53.0 ns 12597184 std::unordered_set<int>::contains(key) (non-existent)/8192 56.1 ns 56.1 ns 12456960 std::unordered_set<int>::contains(key) (expensive-empty)/32 21.4 ns 21.4 ns 32681408 std::unordered_set<int>::contains(key) (expensive-empty)/1024 21.4 ns 21.4 ns 32516640 std::unordered_set<int>::contains(key) (expensive-empty)/8192 21.4 ns 21.4 ns 32573888 std::unordered_set<std::string>::ctor(const&)/32 24879 ns 24880 ns 25856 std::unordered_set<std::string>::ctor(const&)/1024 884089 ns 884042 ns 832 std::unordered_set<std::string>::ctor(const&)/8192 8585689 ns 8585383 ns 96 std::unordered_set<std::string>::ctor(iterator, iterator) (unsorted sequence)/32 29851 ns 29853 ns 22944 std::unordered_set<std::string>::ctor(iterator, iterator) (unsorted sequence)/1024 1149105 ns 1149052 ns 768 std::unordered_set<std::string>::ctor(iterator, iterator) (unsorted sequence)/8192 9769845 ns 9769243 ns 64 std::unordered_set<std::string>::ctor(iterator, iterator) (sorted sequence)/32 33674 ns 33678 ns 26624 std::unordered_set<std::string>::ctor(iterator, iterator) (sorted sequence)/1024 1058258 ns 1058235 ns 544 std::unordered_set<std::string>::ctor(iterator, iterator) (sorted sequence)/8192 9624318 ns 9624047 ns 96 std::unordered_set<std::string>::operator=(const&)/32 48214 ns 48216 ns 15296 std::unordered_set<std::string>::operator=(const&)/1024 1523473 ns 1523422 ns 448 std::unordered_set<std::string>::operator=(const&)/8192 13500351 ns 13499850 ns 64 std::unordered_set<std::string>::insert(value) (already present)/32 324 ns 324 ns 2154816 std::unordered_set<std::string>::insert(value) (already present)/1024 731 ns 731 ns 964224 std::unordered_set<std::string>::insert(value) (already present)/8192 1463 ns 1463 ns 460064 std::unordered_set<std::string>::insert(value) (new value)/32 1005 ns 1004 ns 1843488 std::unordered_set<std::string>::insert(value) (new value)/1024 1299 ns 1191 ns 636960 std::unordered_set<std::string>::insert(value) (new value)/8192 1726 ns 1702 ns 320000 std::unordered_set<std::string>::insert(iterator, iterator) (all new keys)/32 44153 ns 42927 ns 17413 std::unordered_set<std::string>::insert(iterator, iterator) (all new keys)/1024 1476626 ns 1447248 ns 482 std::unordered_set<std::string>::insert(iterator, iterator) (all new keys)/8192 13019197 ns 12896650 ns 55 std::unordered_set<std::string>::insert(iterator, iterator) (half new keys)/32 40150 ns 40125 ns 16551 std::unordered_set<std::string>::insert(iterator, iterator) (half new keys)/1024 1407984 ns 1341443 ns 497 std::unordered_set<std::string>::insert(iterator, iterator) (half new keys)/8192 12215376 ns 12203965 ns 57 std::unordered_set<std::string>::erase(key) (existent)/32 2569 ns 1997 ns 349312 std::unordered_set<std::string>::erase(key) (existent)/1024 1970 ns 1927 ns 930304 std::unordered_set<std::string>::erase(key) (existent)/8192 1621 ns 1618 ns 529216 std::unordered_set<std::string>::erase(key) (non-existent)/32 1174 ns 986 ns 623360 std::unordered_set<std::string>::erase(key) (non-existent)/1024 1194 ns 1048 ns 676672 std::unordered_set<std::string>::erase(key) (non-existent)/8192 983 ns 962 ns 688000 std::unordered_set<std::string>::erase(iterator)/32 213 ns 209 ns 3374560 std::unordered_set<std::string>::erase(iterator)/1024 212 ns 207 ns 3474080 std::unordered_set<std::string>::erase(iterator)/8192 218 ns 206 ns 3805824 std::unordered_set<std::string>::erase(iterator, iterator) (erase half the container)/32 2854 ns 2804 ns 208147 std::unordered_set<std::string>::erase(iterator, iterator) (erase half the container)/1024 64984 ns 64778 ns 10493 std::unordered_set<std::string>::erase(iterator, iterator) (erase half the container)/8192 695737 ns 695149 ns 1013 std::unordered_set<std::string>::clear()/32 1388 ns 1370 ns 506834 std::unordered_set<std::string>::clear()/1024 46217 ns 46073 ns 15204 std::unordered_set<std::string>::clear()/8192 599831 ns 599498 ns 1180 std::unordered_set<std::string>::find(key) (existent)/32 753 ns 753 ns 1039520 std::unordered_set<std::string>::find(key) (existent)/1024 662 ns 662 ns 968320 std::unordered_set<std::string>::find(key) (existent)/8192 610 ns 610 ns 1020864 std::unordered_set<std::string>::find(key) (non-existent)/32 625 ns 625 ns 1117408 std::unordered_set<std::string>::find(key) (non-existent)/1024 655 ns 655 ns 1083008 std::unordered_set<std::string>::find(key) (non-existent)/8192 650 ns 650 ns 1042560 std::unordered_set<std::string>::find(key) (expensive-empty)/32 14.4 ns 14.4 ns 48641472 std::unordered_set<std::string>::find(key) (expensive-empty)/1024 14.4 ns 14.4 ns 48623392 std::unordered_set<std::string>::find(key) (expensive-empty)/8192 14.4 ns 14.4 ns 48591616 std::unordered_set<std::string>::count(key) (existent)/32 824 ns 824 ns 985760 std::unordered_set<std::string>::count(key) (existent)/1024 776 ns 776 ns 929376 std::unordered_set<std::string>::count(key) (existent)/8192 703 ns 702 ns 995936 std::unordered_set<std::string>::count(key) (non-existent)/32 725 ns 725 ns 1087584 std::unordered_set<std::string>::count(key) (non-existent)/1024 709 ns 709 ns 937664 std::unordered_set<std::string>::count(key) (non-existent)/8192 625 ns 625 ns 1144000 std::unordered_set<std::string>::count(key) (expensive-empty)/32 19.3 ns 19.3 ns 36164832 std::unordered_set<std::string>::count(key) (expensive-empty)/1024 19.3 ns 19.3 ns 36393312 std::unordered_set<std::string>::count(key) (expensive-empty)/8192 19.3 ns 19.3 ns 36143328 std::unordered_set<std::string>::contains(key) (existent)/32 709 ns 709 ns 1048064 std::unordered_set<std::string>::contains(key) (existent)/1024 748 ns 748 ns 1024768 std::unordered_set<std::string>::contains(key) (existent)/8192 831 ns 831 ns 895008 std::unordered_set<std::string>::contains(key) (non-existent)/32 714 ns 714 ns 1075264 std::unordered_set<std::string>::contains(key) (non-existent)/1024 504 ns 504 ns 1222240 std::unordered_set<std::string>::contains(key) (non-existent)/8192 717 ns 717 ns 1022432 std::unordered_set<std::string>::contains(key) (expensive-empty)/32 22.0 ns 22.0 ns 31752096 std::unordered_set<std::string>::contains(key) (expensive-empty)/1024 22.0 ns 22.0 ns 31857600 std::unordered_set<std::string>::contains(key) (expensive-empty)/8192 22.0 ns 22.0 ns 31783040 2. Without the opt: ------------------------------------------------------------------------------------------------------------------------------------- Benchmark Time CPU Iterations ------------------------------------------------------------------------------------------------------------------------------------- std::unordered_set<int>::ctor(const&)/32 4920 ns 4921 ns 142304 std::unordered_set<int>::ctor(const&)/1024 161004 ns 161004 ns 4384 std::unordered_set<int>::ctor(const&)/8192 1369984 ns 1369913 ns 512 std::unordered_set<int>::ctor(iterator, iterator) (unsorted sequence)/32 6583 ns 6584 ns 105536 std::unordered_set<int>::ctor(iterator, iterator) (unsorted sequence)/1024 203335 ns 203328 ns 3488 std::unordered_set<int>::ctor(iterator, iterator) (unsorted sequence)/8192 1712738 ns 1712659 ns 416 std::unordered_set<int>::ctor(iterator, iterator) (sorted sequence)/32 6417 ns 6418 ns 105920 std::unordered_set<int>::ctor(iterator, iterator) (sorted sequence)/1024 204252 ns 204248 ns 3456 std::unordered_set<int>::ctor(iterator, iterator) (sorted sequence)/8192 1718282 ns 1718226 ns 416 std::unordered_set<int>::operator=(const&)/32 4777 ns 4778 ns 143776 std::unordered_set<int>::operator=(const&)/1024 155375 ns 155370 ns 4416 std::unordered_set<int>::operator=(const&)/8192 1318345 ns 1318318 ns 416 std::unordered_set<int>::insert(value) (already present)/32 57.1 ns 57.1 ns 12182624 std::unordered_set<int>::insert(value) (already present)/1024 60.2 ns 60.2 ns 11640704 std::unordered_set<int>::insert(value) (already present)/8192 59.3 ns 59.3 ns 11515456 std::unordered_set<int>::insert(value) (new value)/32 152 ns 152 ns 4575936 std::unordered_set<int>::insert(value) (new value)/1024 161 ns 161 ns 4283488 std::unordered_set<int>::insert(value) (new value)/8192 172 ns 172 ns 4288736 std::unordered_set<int>::insert(iterator, iterator) (all new keys)/32 6430 ns 6434 ns 107732 std::unordered_set<int>::insert(iterator, iterator) (all new keys)/1024 206167 ns 206184 ns 3429 std::unordered_set<int>::insert(iterator, iterator) (all new keys)/8192 1587621 ns 1587634 ns 417 std::unordered_set<int>::insert(iterator, iterator) (half new keys)/32 4588 ns 4587 ns 150781 std::unordered_set<int>::insert(iterator, iterator) (half new keys)/1024 132835 ns 132832 ns 4951 std::unordered_set<int>::insert(iterator, iterator) (half new keys)/8192 1095236 ns 1095210 ns 641 std::unordered_set<int>::erase(key) (existent)/32 154 ns 154 ns 4492416 std::unordered_set<int>::erase(key) (existent)/1024 160 ns 160 ns 4383520 std::unordered_set<int>::erase(key) (existent)/8192 155 ns 155 ns 4363744 std::unordered_set<int>::erase(key) (non-existent)/32 57.8 ns 57.8 ns 14141664 std::unordered_set<int>::erase(key) (non-existent)/1024 57.4 ns 57.4 ns 14369216 std::unordered_set<int>::erase(key) (non-existent)/8192 56.4 ns 56.4 ns 13152576 std::unordered_set<int>::erase(iterator)/32 108 ns 108 ns 6519872 std::unordered_set<int>::erase(iterator)/1024 110 ns 110 ns 6271040 std::unordered_set<int>::erase(iterator)/8192 112 ns 112 ns 6295872 std::unordered_set<int>::erase(iterator, iterator) (erase half the container)/32 1815 ns 1808 ns 363644 std::unordered_set<int>::erase(iterator, iterator) (erase half the container)/1024 51034 ns 51007 ns 13752 std::unordered_set<int>::erase(iterator, iterator) (erase half the container)/8192 414144 ns 414067 ns 1692 std::unordered_set<int>::clear()/32 1053 ns 1049 ns 660370 std::unordered_set<int>::clear()/1024 24122 ns 24110 ns 29062 std::unordered_set<int>::clear()/8192 189528 ns 189457 ns 3704 std::unordered_set<int>::find(key) (existent)/32 52.0 ns 52.0 ns 12869664 std::unordered_set<int>::find(key) (existent)/1024 51.0 ns 51.0 ns 13863392 std::unordered_set<int>::find(key) (existent)/8192 52.8 ns 52.8 ns 13966656 std::unordered_set<int>::find(key) (non-existent)/32 43.0 ns 43.0 ns 13238752 std::unordered_set<int>::find(key) (non-existent)/1024 46.9 ns 46.9 ns 17560800 std::unordered_set<int>::find(key) (non-existent)/8192 40.5 ns 40.5 ns 17009920 std::unordered_set<int>::find(key) (expensive-empty)/32 16.4 ns 16.4 ns 42983616 std::unordered_set<int>::find(key) (expensive-empty)/1024 16.5 ns 16.5 ns 42652352 std::unordered_set<int>::find(key) (expensive-empty)/8192 16.3 ns 16.3 ns 42610592 std::unordered_set<int>::count(key) (existent)/32 58.6 ns 58.6 ns 11978688 std::unordered_set<int>::count(key) (existent)/1024 56.3 ns 56.3 ns 12275488 std::unordered_set<int>::count(key) (existent)/8192 61.3 ns 61.3 ns 11718880 std::unordered_set<int>::count(key) (non-existent)/32 51.6 ns 51.6 ns 13867456 std::unordered_set<int>::count(key) (non-existent)/1024 59.7 ns 59.7 ns 12946400 std::unordered_set<int>::count(key) (non-existent)/8192 57.9 ns 57.9 ns 12481344 std::unordered_set<int>::count(key) (expensive-empty)/32 21.5 ns 21.5 ns 32519840 std::unordered_set<int>::count(key) (expensive-empty)/1024 21.5 ns 21.5 ns 32430592 std::unordered_set<int>::count(key) (expensive-empty)/8192 21.5 ns 21.5 ns 32623872 std::unordered_set<int>::contains(key) (existent)/32 58.3 ns 58.3 ns 11878944 std::unordered_set<int>::contains(key) (existent)/1024 61.1 ns 61.1 ns 11275648 std::unordered_set<int>::contains(key) (existent)/8192 59.8 ns 59.8 ns 11298112 std::unordered_set<int>::contains(key) (non-existent)/32 52.4 ns 52.4 ns 11874720 std::unordered_set<int>::contains(key) (non-existent)/1024 56.1 ns 56.1 ns 11843904 std::unordered_set<int>::contains(key) (non-existent)/8192 57.3 ns 57.3 ns 10858048 std::unordered_set<int>::contains(key) (expensive-empty)/32 23.1 ns 23.1 ns 30402240 std::unordered_set<int>::contains(key) (expensive-empty)/1024 23.1 ns 23.1 ns 30244128 std::unordered_set<int>::contains(key) (expensive-empty)/8192 23.1 ns 23.1 ns 30230528 std::unordered_set<std::string>::ctor(const&)/32 26497 ns 26497 ns 25280 std::unordered_set<std::string>::ctor(const&)/1024 825878 ns 825839 ns 832 std::unordered_set<std::string>::ctor(const&)/8192 8670858 ns 8670549 ns 96 std::unordered_set<std::string>::ctor(iterator, iterator) (unsorted sequence)/32 27310 ns 27311 ns 26464 std::unordered_set<std::string>::ctor(iterator, iterator) (unsorted sequence)/1024 946828 ns 946803 ns 768 std::unordered_set<std::string>::ctor(iterator, iterator) (unsorted sequence)/8192 9053635 ns 9053223 ns 96 std::unordered_set<std::string>::ctor(iterator, iterator) (sorted sequence)/32 27548 ns 27548 ns 23648 std::unordered_set<std::string>::ctor(iterator, iterator) (sorted sequence)/1024 898692 ns 898659 ns 800 std::unordered_set<std::string>::ctor(iterator, iterator) (sorted sequence)/8192 9010872 ns 9010567 ns 96 std::unordered_set<std::string>::operator=(const&)/32 47648 ns 47650 ns 14080 std::unordered_set<std::string>::operator=(const&)/1024 1475556 ns 1475497 ns 448 std::unordered_set<std::string>::operator=(const&)/8192 13089133 ns 13088427 ns 64 std::unordered_set<std::string>::insert(value) (already present)/32 946 ns 946 ns 796928 std::unordered_set<std::string>::insert(value) (already present)/1024 729 ns 729 ns 2565824 std::unordered_set<std::string>::insert(value) (already present)/8192 805 ns 805 ns 2718624 std::unordered_set<std::string>::insert(value) (new value)/32 1161 ns 1161 ns 1403360 std::unordered_set<std::string>::insert(value) (new value)/1024 1246 ns 1246 ns 1978080 std::unordered_set<std::string>::insert(value) (new value)/8192 1110 ns 1110 ns 985376 std::unordered_set<std::string>::insert(iterator, iterator) (all new keys)/32 30256 ns 30276 ns 25741 std::unordered_set<std::string>::insert(iterator, iterator) (all new keys)/1024 908942 ns 909062 ns 745 std::unordered_set<std::string>::insert(iterator, iterator) (all new keys)/8192 7286785 ns 7286437 ns 96 std::unordered_set<std::string>::insert(iterator, iterator) (half new keys)/32 26705 ns 26699 ns 26325 std::unordered_set<std::string>::insert(iterator, iterator) (half new keys)/1024 837638 ns 837685 ns 835 std::unordered_set<std::string>::insert(iterator, iterator) (half new keys)/8192 6982924 ns 6982639 ns 100 std::unordered_set<std::string>::erase(key) (existent)/32 1082 ns 1082 ns 1315040 std::unordered_set<std::string>::erase(key) (existent)/1024 815 ns 815 ns 1036096 std::unordered_set<std::string>::erase(key) (existent)/8192 1004 ns 1004 ns 868960 std::unordered_set<std::string>::erase(key) (non-existent)/32 632 ns 632 ns 1007424 std::unordered_set<std::string>::erase(key) (non-existent)/1024 609 ns 609 ns 1200256 std::unordered_set<std::string>::erase(key) (non-existent)/8192 749 ns 749 ns 1040416 std::unordered_set<std::string>::erase(iterator)/32 132 ns 131 ns 5600064 std::unordered_set<std::string>::erase(iterator)/1024 125 ns 125 ns 5720800 std::unordered_set<std::string>::erase(iterator)/8192 130 ns 130 ns 5698336 std::unordered_set<std::string>::erase(iterator, iterator) (erase half the container)/32 2188 ns 2166 ns 329336 std::unordered_set<std::string>::erase(iterator, iterator) (erase half the container)/1024 66079 ns 65889 ns 10574 std::unordered_set<std::string>::erase(iterator, iterator) (erase half the container)/8192 685952 ns 685607 ns 1001 std::unordered_set<std::string>::clear()/32 1388 ns 1372 ns 507157 std::unordered_set<std::string>::clear()/1024 47859 ns 47698 ns 15356 std::unordered_set<std::string>::clear()/8192 573679 ns 573370 ns 1137 std::unordered_set<std::string>::find(key) (existent)/32 728 ns 728 ns 955840 std::unordered_set<std::string>::find(key) (existent)/1024 682 ns 682 ns 926912 std::unordered_set<std::string>::find(key) (existent)/8192 648 ns 648 ns 923872 std::unordered_set<std::string>::find(key) (non-existent)/32 646 ns 646 ns 958112 std::unordered_set<std::string>::find(key) (non-existent)/1024 702 ns 702 ns 1090208 std::unordered_set<std::string>::find(key) (non-existent)/8192 594 ns 594 ns 1150432 std::unordered_set<std::string>::find(key) (expensive-empty)/32 313 ns 313 ns 2236000 std::unordered_set<std::string>::find(key) (expensive-empty)/1024 313 ns 313 ns 2237376 std::unordered_set<std::string>::find(key) (expensive-empty)/8192 313 ns 313 ns 2233696 std::unordered_set<std::string>::count(key) (existent)/32 803 ns 803 ns 987712 std::unordered_set<std::string>::count(key) (existent)/1024 670 ns 670 ns 919680 std::unordered_set<std::string>::count(key) (existent)/8192 668 ns 668 ns 878944 std::unordered_set<std::string>::count(key) (non-existent)/32 706 ns 706 ns 966848 std::unordered_set<std::string>::count(key) (non-existent)/1024 558 ns 558 ns 979904 std::unordered_set<std::string>::count(key) (non-existent)/8192 632 ns 632 ns 1027840 std::unordered_set<std::string>::count(key) (expensive-empty)/32 319 ns 319 ns 2196512 std::unordered_set<std::string>::count(key) (expensive-empty)/1024 318 ns 318 ns 2199328 std::unordered_set<std::string>::count(key) (expensive-empty)/8192 318 ns 318 ns 2197472 std::unordered_set<std::string>::contains(key) (existent)/32 708 ns 708 ns 1037120 std::unordered_set<std::string>::contains(key) (existent)/1024 765 ns 765 ns 889856 std::unordered_set<std::string>::contains(key) (existent)/8192 740 ns 740 ns 945600 std::unordered_set<std::string>::contains(key) (non-existent)/32 730 ns 730 ns 1077984 std::unordered_set<std::string>::contains(key) (non-existent)/1024 662 ns 662 ns 1001536 std::unordered_set<std::string>::contains(key) (non-existent)/8192 662 ns 662 ns 1024864 std::unordered_set<std::string>::contains(key) (expensive-empty)/32 321 ns 321 ns 2182656 std::unordered_set<std::string>::contains(key) (expensive-empty)/1024 320 ns 320 ns 2188096 std::unordered_set<std::string>::contains(key) (expensive-empty)/8192 320 ns 320 ns 2188192
diff --git a/libcxx/test/benchmarks/containers/associative/associative_container_benchmarks.h b/libcxx/test/benchmarks/containers/associative/associative_container_benchmarks.h
@@ -47,6 +47,14 @@ void associative_container_benchmarks(std::string container) {
     return std::vector<Key>(keys.begin(), keys.end());
   };
 
+  auto generate_expensive_keys = [=](std::size_t n) {
+    std::vector<Key> keys;
+    for (std::size_t i = 0; i < n; ++i) {
+      keys.push_back(Generate<Key>::expensive());
+    }
+    return keys;
+  };
+
   auto make_value_types = [](std::vector<Key> const& keys) {
     std::vector<Value> kv;
     for (Key const& k : keys)
@@ -480,17 +488,37 @@ void associative_container_benchmarks(std::string container) {
     };
   };
 
+  auto with_expensive_key_empty = [=](auto func) {
+    return [=](auto& st) {
+        const std::size_t size = st.range(0);
+        std::vector<Key> keys = generate_expensive_keys(size);
+        Container c;
+
+        while (st.KeepRunningBatch(BatchSize)) {
+          for (std::size_t i = 0; i != BatchSize; ++i) {
+            auto result = func(c, keys[i]);
+            benchmark::DoNotOptimize(c);
+            benchmark::DoNotOptimize(result);
+            benchmark::ClobberMemory();
+          }
+        }
+      };
+  };
+
   auto find = [](Container const& c, Key const& key) { return c.find(key); };
   bench("find(key) (existent)", with_existent_key(find));
   bench("find(key) (non-existent)", with_nonexistent_key(find));
+  bench("find(key) (expensive-empty)", with_expensive_key_empty(find));
 
   auto count = [](Container const& c, Key const& key) { return c.count(key); };
   bench("count(key) (existent)", with_existent_key(count));
   bench("count(key) (non-existent)", with_nonexistent_key(count));
+  bench("count(key) (expensive-empty)", with_expensive_key_empty(count));
 
   auto contains = [](Container const& c, Key const& key) { return c.contains(key); };
   bench("contains(key) (existent)", with_existent_key(contains));
   bench("contains(key) (non-existent)", with_nonexistent_key(contains));
+  bench("contains(key) (expensive-empty)", with_expensive_key_empty(contains));
 
   if constexpr (is_ordered_container) {
     auto lower_bound = [](Container const& c, Key const& key) { return c.lower_bound(key); };
diff --git a/libcxx/test/benchmarks/containers/associative/hash_table_find.bench.cpp b/libcxx/test/benchmarks/containers/associative/hash_table_find.bench.cpp
diff --git a/libcxx/test/benchmarks/containers/associative/unordered_map.bench.cpp b/libcxx/test/benchmarks/containers/associative/unordered_map.bench.cpp
@@ -28,6 +28,7 @@ struct support::adapt_operations<std::unordered_map<K, V>> {
 
 int main(int argc, char** argv) {
   support::associative_container_benchmarks<std::unordered_map<int, int>>("std::unordered_map<int, int>");
+  support::associative_container_benchmarks<std::unordered_map<std::string, int>>("std::unordered_map<std::string, int>");
 
   benchmark::Initialize(&argc, argv);
   benchmark::RunSpecifiedBenchmarks();
diff --git a/libcxx/test/benchmarks/containers/associative/unordered_multimap.bench.cpp b/libcxx/test/benchmarks/containers/associative/unordered_multimap.bench.cpp
@@ -27,6 +27,7 @@ struct support::adapt_operations<std::unordered_multimap<K, V>> {
 
 int main(int argc, char** argv) {
   support::associative_container_benchmarks<std::unordered_multimap<int, int>>("std::unordered_multimap<int, int>");
+  support::associative_container_benchmarks<std::unordered_multimap<std::string, int>>("std::unordered_multimap<std::string, int>");
 
   benchmark::Initialize(&argc, argv);
   benchmark::RunSpecifiedBenchmarks();
diff --git a/libcxx/test/benchmarks/containers/associative/unordered_multiset.bench.cpp b/libcxx/test/benchmarks/containers/associative/unordered_multiset.bench.cpp
@@ -8,6 +8,7 @@
 
 // UNSUPPORTED: c++03, c++11, c++14, c++17
 
+#include <string>
 #include <unordered_set>
 
 #include "associative_container_benchmarks.h"
@@ -26,6 +27,7 @@ struct support::adapt_operations<std::unordered_multiset<K>> {
 
 int main(int argc, char** argv) {
   support::associative_container_benchmarks<std::unordered_multiset<int>>("std::unordered_multiset<int>");
+  support::associative_container_benchmarks<std::unordered_multiset<std::string>>("std::unordered_multiset<std::string>");
 
   benchmark::Initialize(&argc, argv);
   benchmark::RunSpecifiedBenchmarks();
diff --git a/libcxx/test/benchmarks/containers/associative/unordered_set.bench.cpp b/libcxx/test/benchmarks/containers/associative/unordered_set.bench.cpp
@@ -8,6 +8,7 @@
 
 // UNSUPPORTED: c++03, c++11, c++14, c++17
 
+#include <string>
 #include <unordered_set>
 #include <utility>
 
@@ -27,6 +28,7 @@ struct support::adapt_operations<std::unordered_set<K>> {
 
 int main(int argc, char** argv) {
   support::associative_container_benchmarks<std::unordered_set<int>>("std::unordered_set<int>");
+  support::associative_container_benchmarks<std::unordered_set<std::string>>("std::unordered_set<std::string>");
 
   benchmark::Initialize(&argc, argv);
   benchmark::RunSpecifiedBenchmarks();
