Extend the base cache clear command adding a little sleep to prevent issus on Windows with "Access denied" on the cache directories.

CacheClearCommand.php

<?php
namespace Althaus\ExtrasBundle\Command;

use Symfony\Component\Console\Input\InputInterface;
use Symfony\Component\Console\Output\OutputInterface;
use Symfony\Bundle\FrameworkBundle\Command\CacheClearCommand as BaseCommand;

class CacheClearCommand extends BaseCommand
{
    /**
     * @see Command
     */
    protected function configure()
    {
        parent::configure();
        $this->setDescription('Clears the cache (incl. Windows workaround)');
        //$this->setName('cache:clr');
    }

    /**
     * {@inheritdoc}
     */
    protected function execute(InputInterface $input, OutputInterface $output)
    {
        $realCacheDir = $this->getContainer()->getParameter('kernel.cache_dir');
        $oldCacheDir  = $realCacheDir.'_old';

        if (!is_writable($realCacheDir)) {
            throw new \RuntimeException(sprintf('Unable to write in the "%s" directory', $realCacheDir));
        }

        $kernel = $this->getContainer()->get('kernel');
        $output->writeln(sprintf('Clearing the cache for the <info>%s</info> environment with debug <info>%s</info>', $kernel->getEnvironment(), var_export($kernel->isDebug(), true)));

        if ($input->getOption('no-warmup')) {
            rename($realCacheDir, $oldCacheDir);
        } else {
            $warmupDir = $realCacheDir.'_new';

            $this->warmup($warmupDir);

            rename($realCacheDir, $oldCacheDir);
            sleep(1);
            rename($warmupDir, $realCacheDir);
        }

        $this->getContainer()->get('filesystem')->remove($oldCacheDir);
    }
}