A: jmeter operating principle:
jmeter when the thread way to run (due jmeter is java so developed is running JVM on a virtual machine, java also supports multi-threading)
Two: jmeter architecture
1. sampler smapler
It used to simulate a user operation, sent to the server (SUT) HTTP peer requests
2. Assertion (checkpoint)
It used to verify the results are correct, with a pre-match results and actual results
3. Listeners
The test results need to add listeners to collect
( 1 ) add the listener, the results can be saved to a file for analysis results can be used again
( 2 ) show the results, the results can be displayed in tabular form and graphics to facilitate the analysis of the results of the test personnel
4. preprocessor
In the script development process, we might do some environmental parameters or in the preparatory work before the request is sent, as the former database operations need to establish a database connection or use the " user parameters " for parameterized user account password
5. Configuration element
Performance testing to simulate a large number of user operations we need to do parameterized, then jmeter parameterization can be accomplished by the configuration element, additionally jmeter also provides a number of functions (function box), to help us generate dynamic data
6. postprocessor
After the post-processor in general sampler for processing the results returned by the server
7. Controller
Control cycles, etc.
8. timer (set point)
In order to simulate real user load enough, we sometimes need to simulate these requests at the same time, if we put the set start simultaneously on the starting line, then we need a set of functions
9. Thread Group
Performance tests need to simulate a large number of user load, thread group is used to accomplish this task, the thread group we can run a number of threads (number of users) is set, the long run, cycle times, etc.
Three: JMeter element run sequence
1. Configuration element
2. preprocessor
3. Timer
4. The sampler sampler
The postprocessor
6. affirm
7. Listeners