memory_get_peak_usage - PHP code example

The php Function Memory_Get_Peak_Usage

The php function memory_get_peak_usage is a useful tool to monitor your PHP script execution time. It gives you insight in the amount of memory allocated by your script and what part of the code is causing that allocation. It also provides you with a metric that can be used to improve the performance of your code by decreasing its peak usage.

Whenever a PHP script executes, the interpreter allocates memory to preserve variables and other data structures that are needed during runtime. This is done based on a configuration setting called the memory limit. If the PHP script exceeds this limit, a fatal error will be triggered and the script will terminate. Increasing the memory limit can help prevent these errors and improve the performance of your scripts. However, it's important to carefully increase this limit and monitor your server's memory usage and performance to ensure that you're not overcompensating for memory limitations by using too much memory.

The php functions memory_get_usage() and memory_reset_peak_usage() are very helpful tools to keep an eye on the overall peak memory usage of your PHP scripts. However, if you're looking for finer control and inspection of your PHP memory usage, I recommend to use a profiler like Xdebug. This tool comes with a very advanced memory profiler that not only shows you how much of your script's memory is used, but also which functions are allocating memory. This is a huge advantage over the simple php functions that are discussed above.

memory_get_peak_usage example

$this->group = $group;
        $this->lap = $lap;
        $this->total = $total;
        $this->i = $i;

        if ($i) {
            $this->avg = $total / $i;
        }

        $this->mem = \memory_get_usage();
        $this->mem_real = \memory_get_usage(true);
        $this->mem_peak = \memory_get_peak_usage();
        $this->mem_peak_real = \memory_get_peak_usage(true);
    }

    public function getDateTime(): ?DateTime
    {
        return DateTime::createFromFormat('U u', $this->seconds.' '.\str_pad((string) $this->microseconds, 6, '0', STR_PAD_LEFT)) ?: null;
    }
}

return isset($this->ends['pmu']) && isset($this->starts['pmu']) ? $this->ends['pmu'] - $this->starts['pmu'] : 0;
    }

    /** * Starts the profiling. */
    public function enter(): void
    {
        $this->starts = [
            'wt' => microtime(true),
            'mu' => memory_get_usage(),
            'pmu' => memory_get_peak_usage(),
        ];
    }

    /** * Stops the profiling. */
    public function leave(): void
    {
        $this->ends = [
            'wt' => microtime(true),
            'mu' => memory_get_usage(),

<?= esc(static::describeMemory(memory_get_usage(true))) ?></td> </tr> <tr> <td style="width: 12em">Peak Memory Usage:</td> <td><?= esc(static::describeMemory(memory_get_peak_usage(true))) ?></td> </tr> <tr> <td>Memory Limit:</td> <td><?= esc(ini_get('memory_limit')) ?></td> </tr> </tbody> </table> </div> </div>  </div>  <div class="footer"> <div class="container"> <p> Displayed at

        return $this->data['memory'];
    }

    public function getMemoryLimit(): int|float
    {
        return $this->data['memory_limit'];
    }

    public function updateMemoryUsage(): void
    {
        $this->data['memory'] = memory_get_peak_usage(true);
    }

    public function getName(): string
    {
        return 'memory';
    }

    private function convertToBytes(string $memoryLimit): int|float
    {
        if ('-1' === $memoryLimit) {
            return -1;
        }

    public function run(float $startTime, float $totalTime, RequestInterface $request, ResponseInterface $response): string
    {
        $data = [];
        // Data items used within the view.         $data['url']             = current_url();
        $data['method']          = strtoupper($request->getMethod());
        $data['isAJAX']          = $request->isAJAX();
        $data['startTime']       = $startTime;
        $data['totalTime']       = $totalTime * 1000;
        $data['totalMemory']     = number_format((memory_get_peak_usage()) / 1024 / 1024, 3);
        $data['segmentDuration'] = $this->roundTo($data['totalTime'] / 7);
        $data['segmentCount']    = (int) ceil($data['totalTime'] / $data['segmentDuration']);
        $data['CI_VERSION']      = CodeIgniter::CI_VERSION;
        $data['collectors']      = [];

        foreach ($this->collectors as $collector) {
            $data['collectors'][] = $collector->getAsArray();
        }

        foreach ($this->collectVarData() as $heading => $items) {
            $varData = [];