Here is something that keeps showing up in my error log. I am also using the lsws wordpress cache plugin:
2018-10-06 15:47:52.373260 [INFO] [141.101.77.254:45048] HttpExtConnector state: 8, request body sent: 0, response body size: -2, response body sent:649, left in buffer: 0, attempts: 0.
2018-10-06 15:47:54.106749 [INFO] [162.158.123.115:64726] Connection idle time too long: 301 while in state: 6 watching for event: 24, close!
2018-10-06 15:47:54.106775 [INFO] [162.158.123.115:64726] Content len: 109, Request line:
POST /wp-admin/admin-ajax.php?_fs_blog_admin=true HTTP/1.1
2018-10-06 15:47:54.106781 [INFO] [162.158.123.115:64726] HttpExtConnector state: 8, request body sent: 109, response body size: -2, response body sent:649, left in buffer: 0, attempts: 0.