Still having the slowness issue...
I think it maybe the time of day certain heavy cron jobs are taking place.
Where can I get a list of all the queries used under the Scheduled Tasks "\core\task\.." when the cron is run?
We currently have automated course back up to run (*****) everytime the cron is called .. every minute! which may impact users taking quizzes that makes moodle not usable.. our mdl_standard_log is very large at over 6.6 GB