Urgent bug of 100% cpu on short interval call

I made some stress test and i was shocked!

I do interval of mili second in the client:

//some call requset to server

In the server i have simple select call with limit and it indexed.

The result:
i got 100% cpu on the graph.

I also checked that test in mongodb and the cpu was normal.

What should i do to fix that?

If you using N1QL post query, index definition and EXPLAIN. Check this out https://dzone.com/articles/designing-index-for-query-in-couchbase-n1ql