PHP Benchmarking

As part of writing code, a developer always should try to optimize and make the code run as efficiently as possible.   While learning PHP, often you may see something as simple as looping through an array as something where it just works.   However, some certain ways of writing code may not use the language’s most efficient operations or built-in functions/methods.

For example, consider looping through an array.  It’s a given that the following examples will result in the same output:

$array= new Array(…);

for($i=0; $i < sizeOf($array); $i++) {

echo $array[$i];

}

is functionally the same as

$array= new Array(…);

$size = sizeOf($array);

for($i=0; $i < $size; $i++) {

echo $array[$i];

}

However, the performance of the calls are completely different. With an array with 1,000 keys the first one will take 891% longer than the equivalent code that pre-calculates the size of the aray.  Obviously, the sizeOf() function takes time and doing it over and over and over has a substantial and significant hit on your application’s performance.   So, just remember that profiling and benchmarking code can really make a difference.  Looping through your array on an old Pentium III server with optimized code may be as fast as unoptimized code on a quad-core Xeon.

Check out some great sites that help show a few of the ways that you can improve your PHP application’s performance by showing benchmarks between different ways to write code.

1. The PHP Benchmark — good examples of the difference between functionally equivalent code.
2. PHP Benchmark Tests — again, good examples with specific results between PHP functions.