CPU is very busy for talking with backend database in compose.io

Hi folks,

I got a critical and annoying performance issue on my App, which is a e-commerce App in Meteor.

I have an nginx machine as load balance in AWS, also another 2 identical AWS machine as Meteor App Server. MongoDB is hosted on compose.io.

I found the traffic between my App Servers and compose.io or let’s say the Network-In traffic is very high like > 100M per minute some time over 300M bytes per minute. CPU is fully working on parsing the data from compose.io which I found from Kadira debug tool.

From the nginx side and network out traffic is quite small. The traffic between App server and compose.io looks like is introduced by external visit like browsing my web app. Because if I cut the nginx load balancer from our app servers and I visit my app server via IP address instead of domain name, there is not much traffic. Then I reconnect nginx load balancer to my app server, traffic starts again and CPU is about 100% busy. In this case, I normally got one app server machine is very busy and another is free. And sometime the busy machine doesn’t have any external connection, CPU is still 100% busy.

I’m wandering how to debug this issue. Any suggestion is welcome.

Thanks a lot,
-Bryan