I am running Apache Bench against a Ruby on Rails XML-RPC web service that is running on Passenger via mod_passenger.
All is fine when I run 1000 requests without concurrency. Bench indicates that all requests successfully complete with no failures. When I run Bench again with a concurrency level of 2, however, requests start to fail due to content length. I am seeing failures rates of 70-80% when using concurrency. This should not happen. The requests I am sending to the web service should always results in the same response. I have used cURL to verify that this is in fact the case.
My Rails log is not showing any errors as well so I am curious to see what content Bench actually received and interpreted as a failure. Is there any way to print these failures?