Concurrency testing is also known as multi-user testing, performed to identify the defects in an application when multiple users login to the application.
It helps in identifying and measuring the problems in system parameters such as response time, throughput, locks/dead locks or any other issues associated with concurrency.
Load runner, one of the widely used commercial performance testing tool, is used for this type of testing. VuGen (Virtual user generator) is used to add a number of concurrent users and the performance of the system is noted.