Doctrine 2 why the first query takes longer?

Perform:
for ($i = 0; $i < 5; $i++) {
 $time = microtime(true);
$em->getRepository('Test\Entity')->findAll();
 echo microtime(true) - $time;
}


The query execution time
0.049312114715576
0.0063920021057129
0.0064208507537842
0.005681037902832
0.0060789585113525
Why the first sample so long? While entities can be different, but the first always work out for much longer.

Cache install - memcache
$config->setMetadataCacheImpl($cache);
$config->setQueryCacheImpl($cache);
$config->setResultCacheImpl($cache);
$config->setHydrationCacheImpl($cache);
September 26th 19 at 06:59
1 answer
September 26th 19 at 07:01
Exactly the problem not found, but likely an issue with the server(dev), T,K on the local machine and production problems not found(

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