I'm using a plugin from WPMU Dev called "MailChimp Integration/MailChimp Sync" on a new multisite of mine. I'm getting some crazy crazy traffic from 3 IPs. 35,000 hits and up inside of 24 hours. After checking the IPs, they are ALL Mailchimp IPs.
After investigating the logs, this plugin is doing API calls and pulls at an alarmingly rapid rate and it's making my server performance suffer very badly.
This multisite has about 50 template sites, but only 10 or so live sites thus far and its traffic is fairly low. I was given this info from the server team at Cloudways who found the problem.
Is this an issue in the plugin side of things or the MailChimp API itself?