PerformanceController.php

<?php

namespace Drupal\system\Controller;

use Drupal\Core\Controller\ControllerBase;
use Drupal\system\Form\ClearCacheForm;
use Drupal\system\Form\PerformanceForm;

/**
 * Controller for performance admin.
 */
class PerformanceController extends ControllerBase {
    
    /**
     * Displays the system performance page.
     *
     * @return array
     *   A render array containing the cache-clear form and performance
     *   configuration form.
     */
    public function build() : array {
        return [
            'cache_clear' => $this->formBuilder()
                ->getForm(ClearCacheForm::class),
            'performance' => $this->formBuilder()
                ->getForm(PerformanceForm::class),
        ];
    }

}