Test: foreach writing ref vs. key

No Description

Historical Results

Based on (1) saved test runs, The test labeled "non-referenced" was (on average) the faster by 0.0162 seconds, (1.997% faster)

non-referenced 100%

referenced 98.003%

The non-referenced test took 0.7929 seconds.
The referenced test took 0.809 seconds.

Nitty-Gritty

Each test case ran 20 random code order iterations consisting of 217,970 loops for a total of 4,359,400 runs.

Line execution difference (0.000004) milliseconds.
Avg difference (0.000) milliseconds per 217,970 loops.
Total difference 16.15 milliseconds for 4,359,400 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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