PHP Benchmarks

Performance comparison of PHP code alternatives.

Test: array_merge vs. + (string keys)

Semantically, array_merge() and + are identical when the arrays contain string keys.

View test history (1) Run this test again Return to test menu

Result: Saved

The test labeled "array_merge()" was the faster by 0.0114 seconds, (1.105% faster)

array_merge() 100%
add operator 98.895%

The array_merge() test took 1.0201 seconds.
The add operator test took 1.0315 seconds.


Each test case ran 20 random code order iterations consisting of 295,842 loops for a total of 5,916,840 runs.

  • Line execution difference (0.000002) milliseconds.
  • Avg difference (0.570) milliseconds per 295,842 loops.
  • Total difference 11.40 milliseconds for 5,916,840 loops

The iteration variablity for Code 1 was (0.2111) milliseconds and Code 2 was (0.2329) milliseconds. The lower and the closer together there values are the more accurate the results are.


The first test, "array_merge()", was:

$array = array_merge($GLOBALS['dummy1'], $GLOBALS['dummy2'], $GLOBALS['dummy3']);

The second test, "add operator", was:

$array = $GLOBALS['dummy1'] + $GLOBALS['dummy2'] + $GLOBALS['dummy3'];

Running: Linux (x86_64:1 GB) PHP (