src/Services/QueuedJobService.php
protected function parseMemory($memString)
    {
        switch (strtolower(substr($memString, -1))) {
            case "b":
                return round(substr($memString, 0, -1));
            case "k":
                return round(substr($memString, 0, -1) * 1024);
            case "m":
                return round(substr($memString, 0, -1) * 1024 * 1024);
            case "g":
                return round(substr($memString, 0, -1) * 1024 * 1024 * 1024);
            default:
                return round($memString);
        }
    }
protected function parseMemory($memString)
    {
        switch (strtolower(substr($memString, -1))) {
            case "b":
                return round(substr($memString, 0, -1));
            case "k":
                return round(substr($memString, 0, -1) * 1024);
            case "m":
                return round(substr($memString, 0, -1) * 1024 * 1024);
            case "g":
                return round(substr($memString, 0, -1) * 1024 * 1024 * 1024);
            default:
                return round($memString);
        }
    }
Convert memory limit string to bytes.
Based on implementation in install.php5

@param string $memString

@return float