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run code in 300+ PHP versions simultaneously
<?php $a1 = array_fill(0, 100000, true); foreach($a1 as $k => $v){ unset($a1[$k]); } var_dump(memory_get_usage()); $a2 = array_map(function($v){ return $v; }, $a1); // capacity is trimmed down. how many resizes are performed? unset($a1); var_dump(memory_get_usage()); $a2[] = true; var_dump(memory_get_usage());
Output for 7.2.0
int(4583032) int(384640) int(384960)
Output for 7.0.0 - 7.0.20, 7.1.0, 7.1.7
int(4546392) int(348000) int(348320)
Output for 7.1.5 - 7.1.6
int(4546736) int(348344) int(348664)
Output for 5.6.0 - 5.6.23
int(1268536) int(219992) int(220216)
preferences:
50.01 ms | 409 KiB | 5 Q