Those are unecessary in server.cfg also the rate command as well, i think problem is bandwidith your upload speed
but your sv_maxrate / sv_minrate sould be 0, meaning HLDS default, and sv_maxupdaterate at best for out of country players should be at 66 and sv_minupdaterate default at max 10, since you forcing client rates with this command and if client doesn't have enought bandwidith it will spike a lot of lagg's, meaning in hight CPU both sides