Even though you set the Clear cookies with each iteration? flag to true, it appears that the same JSESSIONID is being sent for each thread iteration. This was confirmed by looking at the apache webserver logs. To reproduce: 1. Create a script with two Thread Groups, linked by a Module Controller. 2. Add a Cookie Manager set at the 'master' or 'top level Thread Group. 3. Add samplers at the child Thread Group for logging into a sample webserver application that supports sessions. 4. Observe the webserver log shows that each request is sporting the same JSESSION ID.
Thanks, someone else has already reported this, and it has been fixed in the latest code. *** This bug has been marked as a duplicate of 44042 ***
This issue has been migrated to GitHub: https://github.com/apache/jmeter/issues/2054