cron.php is taking 30 minutes to complete

I have noticed that our jobs are running only after 30 minutes which is supposed to run every minute. While digging more, I can see that the cron.php file is taking too much time to execute. I have put the debug values in the cron.php file and found that the below entry is executing for almost half an hour and other tasks are completed very fast.

$jobq->runCycle();

What could be the reason and how to troubleshoot ? I have already enabled the debug logs and can see multiple entries similar to the below one when the above function starts.

Thu Nov 15 11:46:52 2019 [354][1][DEBUG] MetaDataHelper: cache miss for 'mdmhelper_996e7abd5b7443fgc099e55d0255b_vardefs_Home'

What could be the issue ? I'm using Sugar(version 9.0.1)