Hello, 
I'm using: 
Server Information
osTicket Version	v1.15.8 (0daca43) —  Up to date
Web Server Software	Apache
MySQL Version	5.7.38
PHP Version	7.2.34-28+ubuntu18.04.1+deb.sury.org+1
The question is:  how can we get emails fetched several times a minute?  It looks like cron works only once:
 
We make logging inside cron call: 
function run() { //called by outside cron NOT autocron
      global $ost;
      if (!$ost || $ost->isUpgradePending()) return;
  for ($i=0; $i<5; $i++) {
    self::MailFetcher();
    sleep(10);
  }
Start / Finish time for every cycle iteration.
 
0) Start time =2022-06-17 15:04:02
0) Finish time =2022-06-17 15:04:02
1) Start time =2022-06-17 15:04:12
1) Finish time =2022-06-17 15:04:12
2) Start time =2022-06-17 15:04:22
2) Finish time =2022-06-17 15:04:40
Worked time =18
3) Start time =2022-06-17 15:04:40
3) Finish time =2022-06-17 15:04:40
4) Start time =2022-06-17 15:04:50
4) Finish time =2022-06-17 15:04:50
 
Through the logs, it works only once a minute. We wanted  MailFetching run several times a minute, but it doesn't happen.