During the full tally, the first thing DirectAdmin does is a quick rename of the domain .log files to .log.1. This requires an immediate re-opening of the logs so the new values are created and filled. DA would previously send an HUP signal to the master httpd pid, but if your system has: graceful_restarts=1 this will now be respected, and will instead issue a USR1 signal. Note, that any failures in the code (eg: httpd.pid cannot be found or read) will end in DA issuing httpd reload to the task.queue. On systemd boxes, this is a graceful restart anyway.