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: Discarded

The test labeled "add operator" was the faster by 0.0634 seconds, (4.839% faster)

add operator 100%
array_merge() 95.161%

The add operator test took 1.2458 seconds.
The array_merge() test took 1.3091 seconds.


Each test case ran 20 random code order iterations consisting of 289,212 loops for a total of 5,784,240 runs.

  • Line execution difference (0.000011) milliseconds.
  • Avg difference (3.168) milliseconds per 289,212 loops.
  • Total difference 63.35 milliseconds for 5,784,240 loops

The iteration variablity for Code 1 was (11.1110) milliseconds and Code 2 was (7.6061) 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 (