Doctrine detach?

public function execute(InputInterface $input, OutputInterface $output): int
{
        $counter = 0;
        $batchSize = 50;
        $existingDeviceSerialNumbers = ['1', ..........'10000'];

        for ($i = $startSerialNumber; $i <= $stopSerialNumber; $i++) {
            if (in_array((string)$i, $existingDeviceSerialNumbers, true)) {
                continue;
            }

            $entityDto = new Entity(........);
            $this->entityManager->persist($entityDto);

            $counter++;
            $output->writeln(sprintf('count %d', $i));

            if (counter % $batchSize) === 0) {
            	$this->entityManager->flush();
            	$this->entityManager->clear();
                gc_collect_cycles();
            }
        }

        $this->entityManager->flush();

        return Command::SUCCESS;
}