Mariadb - MySQL server has gone away after 1 second of sleep

Question

I'm receiving errors from Mariadb. This is ok:

$db = new mysqli(...);
usleep(1000*1000); // 1 second is ok
$db->query('SELECT 1');

This is not ok:

$db = new mysqli(...);
usleep(1001*1000); // 1.001 second makes MySQL server has gone away
$db->query('SELECT 1');

So, I'm searching for some exactly 1 second timeout. But where? I'm out of ideas...

Answer 1

So, the reason was wrong wait_timeout