What is the use of HTTP Cache Manager and HTTP Cookie Manager for the Jmeter?

Question

What is the use of HTTP Cache Manager and HTTP Cookie Manager 

and how it performs if we enable/disable the options to clear them in each iteration?

Answer 1

Both are to make load test more realistic.

• HTTP Cookie Manager - holds cookies which usually are being used for identifying user session including login information.
• HTTP Cache Manager - represents browser cache. Real browsers download different embedded stuff like images, styles, scripts, etc. during rendering web page but do it only once or based on what specific cache control headers tell.
• Clear above each iteration - if enabled new test cycle starts "clean" i.e. each virtual user will have to log in, fetch all the data, etc. so it'll look like a new user to the system under test. If disabled - it'll just be another test iteration for the same virtual user

So if your idea is to make your test more close to real browser testing you need to use above test elements in combination with HTTP Header Manager and configuring HTTP Request Defaults to tell all the HTTP Samples to download embedded resources and use concurrent pool of 2-5 threads for it.

Answer 2

You should read those 2 docs:

• http://jmeter.apache.org/usermanual/component_reference.html#HTTP_Cache_Manager

• http://jmeter.apache.org/usermanual/component_reference.html#HTTP_Cookie_Manager