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<?php $a1 = array_fill(0, 100000, true); foreach($a1 as $k => $v){ unset($a1[$k]); } var_dump(memory_get_usage()); $a2 = $a1; // capacity will be same as original despite $a1 is empty unset($a1); var_dump(memory_get_usage()); $a2[] = true; var_dump(memory_get_usage());
Output for 7.2.0
int(4582448) int(4582480) int(4582480)
Output for 7.0.0 - 7.0.20, 7.1.0, 7.1.7
int(4545808) int(4545840) int(4545840)
Output for 7.1.5 - 7.1.6
int(4546112) int(4546144) int(4546144)
Output for 5.6.0 - 5.6.23
int(1267360) int(1267424) int(1267560)
preferences:
34.07 ms | 409 KiB | 5 Q