public function collect()
    {
        $properties = [
            'version' => PHP_VERSION,
            'acceleratorEnabled' => false,
        ];

        if ($this->ezcSystemInfo->phpAccelerator) {
            $properties = array_merge(
                $properties,
                [
                    'acceleratorEnabled' => $this->ezcSystemInfo->phpAccelerator->isEnabled,
                    'acceleratorName' => $this->ezcSystemInfo->phpAccelerator->name,
                    'acceleratorURL' => $this->ezcSystemInfo->phpAccelerator->url,
                    'acceleratorVersion' => $this->ezcSystemInfo->phpAccelerator->versionString,
                ]
            );
        }

        return new Value\PhpSystemInfo($properties);
    }