JMeter - Why once only controller runs more than once

Question

I added two request one for login to store the session id and another request to check the load test which requires session id.

I made login request as once only, by ad

Answer 1

• Once per thread : put it under Once Only Controller
• Once when test start : put it under setUp Thread Group
• Once when test end you can put it under tearDown Thread Group
• Once in all test put under If Controller with

${__groovy(${__threadNum} == 1 && vars.getIteration() == 1)}