What affects actual queue processing speed?

I have my config file set up with a batch size of 240 and throttled to one email every 15 seconds. At this rate, my 3,200 emails should have finished sending in 14 hours.

The status column in the queue list has been indicating that it’s processing at about 130 per hour (give or take 20). It’s been 26 hours and there are still over 500 messages left in the queue.

I’m curious to know what would be causing this discrepancy.

You would want to set your delay so that the batch finishes in about 80% of the batch time.

If you batch time is an hour (3600)
set your throttle to 10 seconds
set your batch qty to 240

make sure your domain throttling is off.

How are you sending? Cron or via browser?

I think browser has min 30 seconds between batches so try 3 emails per batch.

I did the first campaign through the browser. I did my second with a cron. There didn’t seem to be any difference in the speed between them.

Thank you. I will try that on the next campaign. It will be a few weeks.