Scheduled optimization – how many per hour?

You should not be running scheduled optimization, until you’ve run the Bulk Optimize and Scan & Optimize. All Bulk operations have a throttle that allows you to space them out, and if you’re still concerned about CPU, perhaps you should look into the EWWW IO Cloud service: https://ewww.io/

Thank you, but what if I want the Scan and Optimize to run in the background and not have a tab open?

Then use wp-cli. Otherwise, I highly recommend that you run it from your browser the first time. It’s resumable, so you can stop and come back later too.

I don’t know how many images the scheduled optimization can actually handle due to php timeouts and such. It will also obey the throttle setting to alleviate performance concerns.

Okay that sounds good. If it obeys the limit of delay X seconds between images I can set it to process an image every say 60 seconds and not impact server too much. Thanks!