HTTP Cache Manager not caching request contents

Question

My test plan:

Test Plan
+ User Defined Variables
++ Thread Group
+++ HTTP Cache Manager
+++ Transaction Controller
++++ Request 1
+++ Transaction Controller
++++ Request 2

After run the test I could at View Results in Table that transfered bytes are the same for both requests. The function of HTTP Cache Manager is void this behavior? Below is an image showing my HTTP request, note that the transfered bytes are the same to all requests.

Real test plan:

Answer 1

Cache manager comes with many conditions listed in documentation, so make sure you review them:

1. The fact that you have "groups of 3" is normal:

   Each Virtual User thread has its own Cache.

   so each request will be executed 3 times, and each user will have own cache

2. It's per URL. So if for items 1.1, 2.1, 3.1, and 4.1 URL is even slightly different, each one will be cached. In that case you will see cache in action only if you are looping on the same request, or on next iteration.

3. Cache Manager decision is based on specific algorithm defined in help. If your request deviate from that algorithm, they won't cache:

   If a sample is successful (i.e. has response code 2xx) then the Last-Modified and Etag (and Expired if relevant) values are saved for the URL. Before executing the next sample, the sampler checks to see if there is an entry in the cache, and if so, the If-Last-Modified and If-None-Match conditional headers are set for the request.

4. Finally there are headers that influence caching, e.g.:

   if Cache-Control header is "no-cache", the response will be stored in cache as pre-expired, so will generate a conditional GET request

   or

   Responses with a Vary header will not be cached.

Answer 2

I usually put the cache manager and the cookie manager at the highest level. Also check if the "clear cache on each iteration " flag is requested. This depends on the application requirements (returning user or new user each time).

And yes, most of the times only static items are cached (css, .js, images) while the html page is usually generated and cannot be cached.