Online PHP editor | perf for fU5oH

<?php $dtArray = array(); $dtArray[] = new DateTime(); $dtArray[] = new DateTime(); foreach($dtArray as $value) { $value = null; } echo "object NOT reference: \n"; var_dump($dtArray); $dtArrayRef = array(); $dtArrayRef[] = new DateTime(); $dtArrayRef[] = new DateTime(); foreach($dtArrayRef as &$value) { $value = null; } echo "object REFERENCE: \n" var_dump($dtArrayRef); $string = array(); $string[] = 'new DateTime();'; $string[] = 'new DateTime();'; foreach($string as $value) { $value = null; } echo "string NOT reference: \n" var_dump($string);

Version	System time (s)	User time (s)	Memory (MiB)
5.6.15	0.003	0.087	18.12
5.6.14	0.013	0.047	18.24
5.6.13	0.007	0.053	18.16
5.6.12	0.010	0.053	20.89
5.6.11	0.010	0.080	21.03
5.6.10	0.003	0.040	21.01
5.6.9	0.000	0.093	20.98
5.6.8	0.003	0.037	20.48
5.5.30	0.007	0.077	18.07
5.5.29	0.010	0.083	17.91
5.5.28	0.017	0.043	20.87
5.5.27	0.003	0.070	20.79
5.5.26	0.007	0.057	20.73
5.5.25	0.020	0.080	20.71
5.5.24	0.017	0.083	20.12

Version

System time (s)

User time (s)

Memory (MiB)

5.6.15

0.003

0.087

18.12

5.6.14

0.013

0.047

18.24

5.6.13

0.007

0.053

18.16

5.6.12

0.010

0.053

20.89

5.6.11

0.010

0.080

21.03

5.6.10

0.003

0.040

21.01

5.6.9

0.000

0.093

20.98

5.6.8

0.003

0.037

20.48

5.5.30

0.007

0.077

18.07

5.5.29

0.010

0.083

17.91

5.5.28

0.017

0.043

20.87

5.5.27

0.003

0.070

20.79

5.5.26

0.007

0.057

20.73

5.5.25

0.020

0.080

20.71

5.5.24

0.017

0.083

20.12