some concepts
- Number of virtual users : that is, the thread group in Jmeter
- Transaction : An interface can be a transaction, multiple interfaces can also be a transaction, a process can be a transaction, and a transaction represents a complete function. It is determined by the tester. It can also be understood as a process of transaction application and response
- Scenario : It can be understood as a specific test case,
Common performance test indicators:
1. Response time (system performance index)
RT for short
Concept : The time it takes for the system to respond to a request
Understanding : When the user initiates a request from the client and ends when the client receives the response returned from the server, the time consumed by this process
Response time = server processing time + network transmission time
2. Throughput (system performance index)
Concept : refers to the number of business requests processed by the system per unit time, which directly reflects the carrying capacity of the server performance
Common throughput measures:
- From a business point of view, the number of businesses per day, the number of businesses per hour, the number of users per day, the number of business visits per day, etc.
- From a network perspective, bytes per day
- From a technical point of view, TPS, QPS
Unit: Byte/S
3. Concurrent number (system performance index)
Concept: at the same time, the number of users who log in to the system and perform business operations (send requests)
Compared with throughput, the number of concurrent users is a more intuitive but also more general performance indicator. In fact, the number of concurrent users is a very inaccurate indicator, because different usage patterns of users will cause different users to issue different numbers of requests per unit time
4. Error rate (system performance index)
ER for short
Concept: The probability of a failed transaction when the system is under load
5.TPS (system performance index)
Concept: the number of transactions per second, the number of services that the server can handle per second
example:
1) A certain system processes 1000 transactions per minute, then TPS=1000/60=16.7
2) According to last year's operating data, there will be 100,000 transactions in the highest day in 2022. How many qualified TPS will be predicted in 2023?
Theoretically, TPS=100000/86400=1.2, which is only calculated on average, obviously not
If there is no detailed data, calculate according to the 28th law (0.8 transaction is completed within 0.2 time):
100000*0.8/(86400*0.2)=4.6
If there are more detailed data, for example, 50,000 transactions are completed at 8-9 o'clock
TPS=50000/3600=13.9
But this is only last year, this year's calculation is based on 30% business growth
So TPS=50000*1.3/3600=18
6.QPS (system performance index)
Concept: the number of queries per second, the number of requests that the server can handle per second
7. CPU (resource performance index)
The CPU, also known as the central processing unit, is used to interpret computer instructions and process data in computer software.
8. Memory (resource performance indicators)
The memory is the bridge to communicate with the CPU.
All programs in the computer run in the memory, so the performance of the memory has a great impact on the computer.
The current operating system stores caches in the memory in order to maximize memory utilization, so 100% memory utilization does not mean that there is a bottleneck in the memory. To measure whether the system memory has a bottleneck mainly depends on the utilization of
SWAP (swapping with virtual memory). Generally, the utilization of SWAP is lower than 70%. Too much swapping will cause poor system performance.
9. Disk throughput (resource performance indicator)
Disk throughput is referred to as Disk Throughput for short, which refers to the amount of data passing through the disk per unit time without disk failure.
10. Network throughput (resource performance index)
Network throughput is referred to as Network Throughput for short, which refers to the amount of data passing through the network per unit time without network failure, and the unit is Byte/s
The network throughput index is used to measure the system's demand for network equipment or link transmission capabilities. When the network throughput index is close to the maximum transmission capacity of the network equipment or link, it is necessary to consider upgrading the network equipment
The network throughput index mainly includes how many megabytes of traffic flow in and out per second, and generally cannot exceed 70% of the maximum transmission capacity of the device or link