Eneperf generates error messages in various error conditions.
It is also possible for error messages to be displayed during normal operation. For example, if the log file contains a request to retrieve a record that is not present in the MDEX Engine data set, Eneperf (as expected) presents a 404 (file not found) message.
Note
Queries that cause HTTP errors are not counted towards ops/sec performance results displayed by Eneperf.