JMeter: How to utilize token generated at runtime on multiple thread groups

Question

Scenario is we are generating token during execution which would further be used in other threadgroup.

Like:

In first thread group, tokens will be generated for 100 users. In second thread group, 50 users will utilize the tokens. In third thread group, next 50 users will utilize the tokens.

Query is: 1. How do we save tokens that is generated during run time? 2. How to use first 50 tokens on second thread group and rest other 50 on third thread group?

Answer 1

If you need to use a Token generated by a request in following requests then use 1 Thread Group and not many.

Threads in different ThreadGroup have absolutely no relation and are considered as different users, so although you may use elements like InterThreadCommunication to do that, just DON'T.

If you use same thread group then it's just a matter of using the correct extractor to generate variables and then use them using ${varName}.

Answer 2

You can transfer a value between Thread Groups by converting it into a JMeter Property. According to the documentation:

Properties are not the same as variables. Variables are local to a thread; properties are common to all threads, and need to be referenced using the __P or __property function.

So if you need to transfer something from one thread group into another:

1. Convert the value into a JMeter Property using __setProperty() function like:

   ${__setProperty(foo,bar,)}
   

2. Once done the value can be accessed usine __P() function like

   ${__P(foo,)}
   

Demo:

If the value is different for different threads - you can combine the above approach with __threadNum() or __counter() functions in order to use current virtual user number or next incremented number as a prefix or a postfix for the function.