Online PHP editor | perf for YogUP

<?php $allTheThings = [ ['stuff' => [ ['id' => 42], ]], ['stuff' => [ ['id' => 'never'], ]], ['stuff' => [ ['id' => 'gonna'], ]], ['stuff' => [ ['id' => 'give'], ]], ['stuff' => [ ['id' => 'you'], ]], ['stuff' => [ ['id' => 'up'], ]], ['stuff' => [ ['id' => 42], ]], ['stuff' => [ ['id' => 'never'], ]], ['stuff' => [ ['id' => 'gonna'], ]], ['stuff' => [ ['id' => 'let'], ]], ['stuff' => [ ['id' => 'you'], ]], ['stuff' => [ ['id' => 'down'], ]], ['stuff' => [ ['id' => 42], ]], ]; $t = microtime(true); for ($i = 0; $i < 10000; $i++) { // original code $ids = []; foreach ($allTheThings as $thing) { $ids = array_merge($ids, array_column($thing['stuff'], 'id')); } $ids = array_unique($ids); } $t = microtime(true) - $t; var_export($ids); echo 'original: '.$t."\n"; $t = microtime(true); for ($i = 0; $i < 10000; $i++) { // improved code $allTheIds = array_map(function ($thing) { return array_column($thing['stuff'], 'id'); }, $allTheThings); $ids = array_unique(array_merge(...$allTheIds)); } $t = microtime(true) - $t; var_export($ids); echo 'improved: '.$t."\n"; $t = microtime(true); for ($i = 0; $i < 10000; $i++) { // new code $ids = []; foreach ($allTheThings as $thing) { $ids[array_column($thing['stuff'], 'id')] = 1; } } $t = microtime(true) - $t; var_export($ids); echo 'new: '.$t."\n";

Version	System time (s)	User time (s)	Memory (MiB)
7.2.9	0.060	0.070	14.72
7.2.8	0.093	0.119	14.89
7.2.7	0.007	0.080	15.20
7.2.6	0.009	0.080	15.25
7.2.5	0.010	0.066	15.02
7.2.4	0.016	0.068	14.82
7.2.3	0.020	0.062	15.02
7.2.2	0.012	0.071	15.02
7.2.1	0.039	0.077	15.12
7.2.0	0.012	0.077	14.82
7.1.21	0.144	0.218	14.09
7.1.20	0.068	0.104	13.87
7.1.19	0.061	0.126	13.70
7.1.18	0.032	0.115	13.85
7.1.17	0.022	0.120	13.74
7.1.16	0.042	0.112	13.76
7.1.15	0.022	0.110	14.09
7.1.14	0.028	0.116	13.96
7.1.13	0.022	0.100	13.87
7.1.12	0.032	0.148	13.66
7.0.31	0.039	0.121	13.71
7.0.30	0.040	0.118	13.60
7.0.29	0.019	0.122	13.55
7.0.28	0.055	0.139	13.56
7.0.27	0.049	0.119	13.64