Результатом выполнения данного примера
будет что-то подобное:
Warning: [memtrack] [pid 26177] user function foo() executed in /tmp/example1.php on line 10 allocated 4194304 bytes in /tmp/example1.php on line 0
Warning: [memtrack] [pid 26177] virtual memory usage on shutdown: 32911360 bytes in Unknown on line 0