Test: foreach writing ref vs. key

No Description

Historical Results

Based on (3) saved test runs, The test labeled "non-referenced" was (on average) the faster by 0.024 seconds, (2.278% faster)

non-referenced 100%

referenced 97.722%

The non-referenced test took 1.0288 seconds.
The referenced test took 1.0528 seconds.

Nitty-Gritty

Each test case ran 20 random code order iterations consisting of 256,604 loops for a total of 5,132,073 runs.

Line execution difference (0.000005) milliseconds.
Avg difference (0.000) milliseconds per 256,604 loops.
Total difference 23.98 milliseconds for 5,132,073 loops

The iteration variablity for Code 1 was (0.0000) milliseconds and Code 2 was (0.0000) milliseconds. The lower and the closer together there values are the more accurate the results are.

Code

The first test, "non-referenced", was:

foreach ($GLOBALS['dummy'] as $k => $v)
	$GLOBALS['dummy'][$k][1]++;
unset($v);

The second test, "referenced", was:

foreach ($GLOBALS['dummy'] as $k => &$v)
	$v[1]++;
unset($v);

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