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1. Analyze performance requirements . Select the scenarios that users use most frequently to test , such as ： land , Search for , Order and so on . Determine performance indicators , such as ： The transaction pass rate is 100%,TOP99% yes 5 second , The maximum concurrent users are 1000 people ,CPU And memory usage in 70% following

2. Make a performance test plan , Define the test time ( Usually after the function is stable , Such as after the first round of testing ) And test environment and test tools

3. Write test cases

4. Set up the test environment , Prepare the test data

5. Write performance test scripts

6. Performance test script tuning . Set checkpoint 、 A parameterized 、 relation 、 Marshal Point 、 Business , Adjust your thinking time , Remove redundant scripts

7. Design test scenarios , Run the test script , Monitoring server ,

8. Analyze test results , Collect relevant log bills of lading for development

9. Regression performance test

10. Write test report

2、 How to determine the maximum load of the system ？

Pass load test , Increasing the number of users , As the number of users increases , Each performance index will change accordingly , When there is a performance inflection point , such as , When the number of users reaches a certain order of magnitude , A sudden increase in response time , Then the number of users corresponding to this inflection point is the maximum number of users that the system can carry .

3、 Where do you system ( What functions ) Performance testing was done ？

The most frequently used function of users is selected for testing , such as ： land , Search for , place order

4、 How do you determine the number of concurrent users ？

1） Will be online for a while , Based on the collected user access data, estimate

2） To determine according to demand （ Use peak hours , Number of registered users , Single response time, etc

5、 Where do you run your performance tests ？

Refer to the answer ： We will build a set of independent performance test environment for testing

6、 When do you perform the performance test ？

The benchmark ： After the function test , Do it when the system is stable .

The load test ： All is quiet at dead of night , When the system is not used

7、 How to analyze performance test results ？

First of all, check the pass rate of things , Then analyze other performance indicators , such as , Confirm response time , Transaction pass rate ,CPU Whether the indicators meet the needs ; If the test results are not credible , Analyze the cause of the abnormality , Retest after modification

8、think_time What is the role of ？

Simulate real production user operation , Look at the impact on the server .

After confirming that the performance test results are reliable , If the following problems are found , Follow the ideas below to locate the problem

Question 1 ： Response time not up to standard

Check whether the time consumed by the transaction is mainly in the network transmission or the server , If it's the Internet , Just combine Throughput( Network throughput ) chart , Is there a bottleneck in computing bandwidth , If there is a bottleneck , Consider increasing bandwidth , Or compress the data transmission ; If there is no bottleneck , that , Maybe it's the instability of the Internet . If the main time is spent on the server , Just look at it separately web Server and database server CPU, Is the memory usage too high , Because it's too high CPU, Memory is bound to cause long response times , If it is web Server issues , Just put web Take down the corresponding user operation log on the server , Send development orientation ; If it's a database problem , Take down the corresponding log on the database server , Send development orientation .

Question two ： The server CPU Indicators are abnormal

Analysis methods ： Just put web Take down the corresponding user operation log on the server , Send development orientation .

Question 3 ： database CPU Indicators are abnormal

Analysis methods ： Take down the corresponding log on the database server , Send development orientation .

Question 4 ： Memory leak

Analysis methods ： Put the memory heap Take out the data , Analyze which object consumes the most memory , Then send it to the development location .

Question five ： The program runs successfully in the single user scenario , Multi user operation fails , Prompt that the server cannot be connected .

reason ： The program may be a single threaded processing mechanism

9、 How to identify system bottlenecks ？

from TPS Index analysis ,TPS That is, the number of transactions processed by the system per unit time . Observe whether the number of transactions that the system can process per second will increase with the number of users