PHP debug_backtrace in production code to get information about calling method?

Question

Is there a compelling reason to not use debug_backtrace for the sole purpose of determining the calling method\'s class, name, and parameter list? Not for debugging purposes

Answer 1

I did another performance test of debug_backtrace method. To simulate real stacks i defined several classes which call another class methods randomly - with a specified DEPTH:

a = $foo;
        $bar->a = $foo;

        $foo->a = $bar;
        $alice->b = $bar;

        $foo->b = $alice;
        $bar->b = $alice;

        $this->a = $foo;
        $this->b = $bar;
    }

    public function method($depth)
    {
        BACKTRACE ? debug_backtrace() : null;
        $obj = mt_rand(0,1) === 1 ? $this->a : $this->b;

        if ($depth > DEPTH) {
            return;
        }
        $obj->method($depth+1);

    }
}

class Foo
{
    public $a;
    public $b;

    public function method($depth)
    {
        BACKTRACE ? debug_backtrace() : null;

        $obj = mt_rand(0,1) === 1 ? $this->a : $this->b;

        if ($depth > DEPTH) {
            return;
        }
        $obj->method($depth+1);
    }
}

class Bar
{
    public $a;
    public $b;
    public function method($depth)
    {
        BACKTRACE ? debug_backtrace() : null;
        $obj = mt_rand(0,1) === 1 ? $this->a : $this->b;

        if ($depth > DEPTH) {
            return;
        }
        $obj->method($depth+1);
    }
}

class Alice
{
    public $a;
    public $b;

    public function method($depth)
    {
        BACKTRACE ? debug_backtrace() : null;

        $obj = mt_rand(0,1) === 1 ? $this->a : $this->b;

        if ($depth > DEPTH) {
            return;
        }

        $obj->method($depth+1);
    }
}


$test = new TestClass();

$startWhole = microtime(true);
for($i = 0; $i < 10000;$i++) {
    $start = microtime(true);
    $test->method(0);
    $end = microtime(true);
}
$endWhole = microtime(true);
$total = $endWhole - $startWhole;

echo 'total time: ' . $total . "s\n";

Result:

Performance (10.000 iterations / stack depth 30 / PHP 7.2):

with debug_backtrace - total time: 0.86011600494385s
without:             - total time: 0.043321847915649s 

using debug_backtrace makes this code 20x times slower.