Sending Emails Slowly

i don't know why my mail sending slowly. i tweaked the Cron job settings and other setting from where i can increase sending speed. is this the last step to increase sending speed "Parallel sending via PCNTL" ? i want to send 1 to 5 Million per day, but currently it takes 4 day's to deliver 1 Million !! on the other hand i have Interspire installed on the same server but that can send 1 to 3 Million per day.

Can you please Give me any solution ASAP.


Can you share a screenshot with your settings as shown at backend > settings > cron ?
Some information about the server specs would also help.

Related to pcntl sending, for now it has a issue, hopefully fixed in dev. If you want to use it, PM me and i can give you the fixed file.
DO NOT set subscribers at once to 10K.
I am writing a detailed article now. please wait for me to update this thread with the link.