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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 $a2[] = true; var_dump(memory_get_usage()); unset($a1); var_dump(memory_get_usage());
Output for 7.3.0 - 7.3.1
int(4586352) int(8784864) int(4586384)
Output for 7.2.0 - 7.2.13
int(4582408) int(8780920) int(4582440)
Output for 7.1.25
int(4545736) int(8744248) int(4545768)
Output for 7.0.0 - 7.0.20, 7.1.0, 7.1.7
int(4545808) int(8744320) int(4545840)
Output for 7.1.5 - 7.1.6
int(4546112) int(8744624) int(4546144)
Output for 5.6.0 - 5.6.23
int(1267360) int(1267872) int(219056)
preferences:
49.11 ms | 412 KiB | 5 Q