How to fail jMeter tests when Exception is thrown by the Webapp?

Question

Sometimes, when I run many threads to simulate a server overload, the application throws some exceptions (like DB related exceptions, org.hibernate.exception.GenericJDBCException: Could not open connection), that's ok. However, jMeters reports show error count equals to 0.

How can get this kind of errors to show up in a jMeter report?

Answer 1

If these errors are exposed at the web pages somehow i.e. "Exception" or "Error" word is present you can consider adding a Response Assertion to check that the page does NOT contain "Exception" word. Similarly you can use assertions to check that response matches your expectations.

However according to JMeter Performance and Tuning Tips guide, assertions have cost so use them with caution.

If there is no explicit affect you need to determine implicit impact, i.e. increased response time, timeouts, missing results, etc.

Answer 2

The response assertion helped me as well, but I'm not quite sure how "bad" it is to use this, the Jmeter Performance and Tuning Tips guide, actually recommends it, it only says to avoid other assertions such as XML, but obviously all checks will add memory

From the tuning and tips guide:

Use Response Assertion or Size assertion

These 2 implementations fit 99% of requirements.

Avoid costly ones as: XML Assertion XML Schema Assertion XPath Assertion