i have a program which use to send group emails, i set a cornjob per mins for this program, and set execute per 2nd/min, and check if the now time is match to my defined schedu
First of all. 10000 emails with 3 per minute will take over 2 days.
Secondly, the best way to do this is to save the emails to database (to, title, body etc) and then create a script that sends out 3 emails and set the cronjob to run every minute.
Also check out these questions.