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.

Run this test again Return to test menu

Result: Discarded

The test labeled "add operator" was the faster by 0.0939 seconds, (8.163% faster)

add operator 100%
array_merge() 91.837%

The add operator test took 1.0563 seconds.
The array_merge() test took 1.1502 seconds.


Each test case ran 20 random code order iterations consisting of 247,342 loops for a total of 4,946,840 runs.

  • Line execution difference (0.000019) milliseconds.
  • Avg difference (4.695) milliseconds per 247,342 loops.
  • Total difference 93.90 milliseconds for 4,946,840 loops

The iteration variablity for Code 1 was (10.4059) milliseconds and Code 2 was (7.8555) 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 (