2021-10-19 performance test

One 、 Interface performance test process
1. It's usually like this The requirements specification specifies which function point has performance requirements , And performance indicators .
2. And then we PM And test developers will analyze how to do this requirement , Then make a plan , When will it be finished , When will the performance problem be fixed .
3. Then when the environment tools are ready , Start doing interface performance .
4. Here's how it works , use jmeter Tools , Create a new thread group , Create a new one http request , Then fill in the request address 、 Port number 、 Request method 、 Request parameters . Then add an assertion . Add aggregation report and number of results to view the results . First, a concurrent debugging interface , Parameterize the interface after it succeeds . The parameterization is like this , Add a configuration component csv set config Then read the parameterization file , Parameterize variables . Then replace this variable in the request parameter . Then set the number of threads , Set the number of threads as much concurrency as you need . Generally increase slowly . Before running the performance test , We will install one on the server nmon Tools , Monitor server performance . Then run the performance test . View the aggregation report after running , Look at the physical success rate , Response time and other indicators , Does it meet the requirements . Go to the server and download the server performance index , See if the server performance indicators meet the requirements , Have unsatisfied needs , Send to development , Let the developer analyze the reason for the modification . After development and modification, we will return to verify . Write down the test report after the verification .

Two 、 Performance problems encountered
1、 Things have a high failure rate
2、 Response time is too long
3、CPU Utilization is too high
The reason is that the algorithm is too low , Logic is too complicated .
The database is not indexed , Low query efficiency .

3、 ... and 、 Performance indicators
1、 response time Request from user The time between receiving the data returned by the server .
2、 throughput Unit time The system processes the data requested by the client
3、 Concurrency number Unit time Number of requests submitted to the system .
4、 Resource utilization CPU Memory IO
5、tps The number of things processed per second .

Four 、 How to test maximum concurrency and optimal concurrency
Maximum concurrency ： The maximum number of concurrent users is obtained when the throughput is no longer increased .
Optimal concurrency ： Keep pressurizing until the system index is optimal , Resources are not wasted , Response time is optimal .

5、 ... and 、CPU Causes of high and memory leaks
CPU Too high, right SQL Statements to optimize , Add index .
Memory leak ： Some threads need to be released after execution .

6、 ... and 、 When do you usually start performance testing ？
After the functional test .

7、 ... and 、 What are the performance test methods , And the purpose .
The benchmark ： Make sure there is no problem with the test environment , Preliminary evaluation of a single transaction runtime , Whether the response time of the current system is fast enough , Of each server CPU, Whether the memory consumption is reasonable .
Single transaction concurrency test ： Ensure that there are no thread deadlock and other problems in the database , Evaluation when only a single transaction is running , Whether the response time of the system is fast enough ,CPU, Whether the memory consumption is reasonable .
Mixed scenario test ： Simulate real scene , Evaluate whether the response time of each transaction of the system is fast enough ,CPU, Whether the memory consumption is reasonable .
The load test ： Gradually pressurize , Calculate according to business and data , Pressurize until the performance index meets the demand , Test that the system can withstand the maximum load pressure .
Pressure test ： Gradually pressurize , Focus on when the system reaches the critical point , Record concurrent users when they reach the critical point , Click through rate , And throughput .
Stability test ： Perform stability tests while meeting the business load , Run for a long time to check the operation of the system .
Large capacity test ： Generally for databases , For specific storage , Statistics , Test of query business .

8、 ... and 、 What's the use of thinking about time .
Simulate real user operations .

Nine 、 relation checkpoint Marshal Point thing A parameterized .
relation ： The last output is the next input Manual Association Automatic association .
checkpoint ： Judge whether a thing is successful .
thing ： It's a series of operations , For example, login can be regarded as a thing .
Marshal Point ： The user will wait at one time , When the quantity is reached, release it together . For example, when the specified number is reached, log in together .

Ten 、 Performance measurement .
Test whether the performance meets the requirements .

11、 ... and 、 How to judge whether to do performance test ？
Whether it is the core function , Number and frequency of users . Or performance problems .

Twelve 、 What is stress testing What is load testing What is performance testing ？

13、 ... and 、 How to ensure that the performance test is effective .
Requirements from the beginning Use cases Environmental Science The tool began to answer .

fourteen 、 How to manually associate .LR
1. Record two copies of the same script
2. Check for differences
3. Determine whether you need to associate .
4. Find the left and right boundaries .
5. The playback .

15、 ... and 、 Server resource monitoring .
nmon

sixteen 、 Performance concerns .

seventeen 、 How to locate performance problems .