1. JMeter's
workWhat is the principle? Submits a request to the server, and the result returned from the server retrieval request. 2. What is the role of JMeter? JMeter can be used to test the performance of static or dynamic resources (files, Servlets, Perl scripts, Java objects, databases and queries, FTP servers, or other resources). JMeter is used to simulate the ability to attach high loads on servers, networks, or other objects to test the compression capabilities of their services, or to analyze the overall performance of the services they provide under different load conditions. You can use the graphical interface provided by JMeter to analyze performance metrics or test server/script/object behavior under high load conditions. 3. How can I see the script examples provided by JMeter? Under the \jmeter\jakarta-jmeter-2.0.3\xdocs\demos directory. 4. How do I set the number of concurrent users? Select the Test Plan node for the left tree in the visual interface, right-click and select the Add-> Thread Group, where the number of threads parameter is used to set how many users send the request. 5. Operating instructions for JMeter? JMeter at run time, there is a small box in the upper right corner, which is run as green, and the box is white when finished running. 6. What is the role of User parameters? Increase the availability of scripts 7. In result, there will be a color font of HTTP response code, explain what? The HTTP response code is the HTTP return value, the color font is more noticeable, can use the user quick attention. Like a green 302. In this step, the return value is taken from the native catch, not
Server。 8. How to calculate ramp-up period time? Ramp-up period is the total time interval, in seconds, that occurs for each request. If number of threads is set to 5 and ramp-up period is 10, then the interval between each request is 10/5, or 2 seconds. Ramp-up period is set to 0, which is simultaneous concurrent requests. 9. What is the difference between get and post? They are 2 different implementations of the HTTP protocol. Get refers to the server getting the required parameters from the request URL. As you can see from the request in result, get can see the parameters, but the post is actively sending parameters to the server, so these parameters are not generally seen. 10. What are the causes that could lead to error generation? A. HTTP errors, including not responding, results not found, data errors and so on; B. JMeter itself causes errors. 11. Why is the total value in the aggregate report result not a true sum? JMeter the definition of total in the result is not exactly the sum, for ease of use, its value represents the column's representative value, such as the Min value, and it's total is the minimum value of the column. Is the meaning that total has in each column. 12. is the thread number of jmeter a feature that provides multiple different user concurrency? No, Thread number simply refers to concurrency, and if you need to implement multiple different user concurrency, we should use other methods, such as the way to create a CSV file outside of JMeter. 13. At the same time concurrent requests, if you need to simulate different users simultaneously to different server concurrent requests, how to implement it? The method is flexible and we can pre-write different servers in thread. or write a fixed variable value to a CSV file beforehand, which can also be easily modified. Then add the file to user Parameters. 14. What does the dummy in User parameter mean? The next line that is used to simulate reading a file when its specific content is ${__csvread (${__property (User.dir)}${filename},next ())}. 15. What should I do when a test object jumps between multiple servers? While the program is running, some HTTP and implicit functions carry additional server IPs, which we can get from their return values. 16. Why is the test object an HTTP and https promiscuous occurrence? HTTPS is an encryption protocol, it is generally not recommended to use HTTP for security, but in some places, using HTTPS is too complex or difficult to implement, using the HTTP protocol. 17. What is the default port for HTTP and HTTPS? The default port for Apache server (Http) is $443, and the default port for SSL (HTTPS) is. 18. Why do some pages fail when run, but don't affect the results at the end? There are a number of reasons why it is worth mentioning because there is no dependency on the main page, so even if such a page goes wrong, it will not affect the normal results of the run, but this affects the results of the test and the results of the analysis. 19. Why did the script start running with errors and later scripts to run? There are settings in the thread group, and if Continue is selected, the entire thread will run until the end, even if there is an error in the previous script. Selecting Stop thread ends the current thread, and selecting Stop test ends all thread. The recommended option is stop Thread. 20. in regular expression_r extractor will see the value of the template is $1$, what does this value mean? $1$ refers to the value inside the first (). If the number of regular expression_r is multiple, this method can avoid unnecessary trouble.
21. What does regular expression_r (. *) mean? That is a regular expression (regular Expression_r). ’.’ Equivalent to the '? ' in the SQL language, indicating dispensable. ' * ' means 0 or more. ' () ' indicates that a value needs to be taken. (. *) to express a string of any length. 22. What to pay attention to when reading regular expression_r? Be sure to ensure the absolute uniqueness of the values taken. 23. How can I tell what kind of situation needs to add regular Expression_r Extractor? Check the Send Parameters in the HTTP request, and if one of the parameters is not given in the previous page, look in the original file and add the HTTP regular expression_r extractor to its previous page The request. 24. What does it mean when an empty HTTP request is sometimes present in a script that gets automatically? is because there are some errors in getting the script, which is why the script tool. This error is not involved in running at run. 25. Why is there a rate of N/A in the results of the operation? It is possible to get the correct results by running again because of jmeter problems. 26. What are the common HTTP error codes? 400 the request cannot be resolved. 403 Forbidden Access: Access is denied. 404 file or directory not found. 405 The HTTP action used to access the page is not licensed. 410 file has been deleted. 500 Server Internal error. 501 The configuration specified by the caption value is not executed. An invalid response was received by the 502 Web server as a gateway or proxy server. 27. What does the send parameters in http request mean? Refers to the values written in code and the values obtained in the custom variables, which are the parameters that are required when the page is run. 28. parameters in the page is constantly passing? Yes. After the parameter is generated, it is passed to the desired page in the page. So we can catch it when the dynamic parameter is generated, or it can be captured on the previous page of the desired page. (However, there may be errors, preferably in the resulting page fetch) 29. In the use of JMIs the user operation fully simulated when eter testing? Does the result be exactly the same as the user's operation? Yes. The JMeter fully simulates the user operation, so the operation records are all written to the DB. Error data can be generated when a run fails, depending on whether the script check is rigorous or the error data goes into DB, causing a lot of trouble for the program to run.
JMeter Frequently Asked questions
