Asterisk systemd file

Hello,
i am testing Asterisk(16.0) vs Freeswitch(1.9 master)
firstly , i try to run asterisk on systemd file with pjsip sip stack. asterisk performance is satisfied even with high number of retransmission.
i try to increase performance with thread parameter at [system] section. and then i realize that asterisk runs with no-fork method ,defined in systemd file. after change it with Fork , retransmission numbers are decreased.
is it a misstype or is there purpose?

In addition , 90 cps , duration 15 sec and total call number 5000.
there is 3640 INVITE retransmission.

/usr/sbin/asterisk -mqf -C /etc/asterisk/asterisk.conf

Usage: asterisk [OPTIONS]
Valid Options:
   -V              Display version number and exit
   -C <configfile> Use an alternate configuration file
   -G <group>      Run as a group other than the caller
   -U <user>       Run as a user other than the caller
   -c              Provide console CLI
   -d              Increase debugging (multiple d's = more debugging)
   -f              Do not fork
   -F              Always fork