I have 1 single website running on 1 single Amazon EC2 instance (Linux, Medium size). Our website is based on WordPress and it has W3 Total Cache enabled
+ Page cache - except for logged-in users + Object cache + Browser cache
I have noticed that there is a huge difference between the number of active visitors and the number concurrent connections to our web server at 1 point of time.
At 1 point, there were only 5 active visitors but there was 100+ concurrent connections to our server (determined by
netstat -plan | grep :80 | wc -l).
At another point, there were 10 active visitors but there were 50 and more concurrent connections to our web server.
Can anyone give me some hints on what directions should I go about troubleshooting this issue (I call an issue since 168 concurrent connections caused our server to be down yesterday, when we were still using small EC2 instance)?