A concurrent and online
Concurrency: refers to multiple users at the same time, jointly perform an operation; concurrent testing requirements more stringent, systematic study focused instantaneous pressure **
Online: multiple users over a period of time to perform an operating system (refer to the online multi-user operating cycle an action)
two, request response
Transmission start time means a request from a client, the client receives the result of the timing in response returned from the server end.
In some tools, commonly referred to as a leave request response TTLB (Time to last byte: sending a first request from the beginning, until the client receives the last byte of the response time taken)
unit request response generally "second" or "millisecond"
Request response time = time + client network time (transfer time) + server time
the actual project testing process, the test system is often deployed to the network environment so that there is sufficient bandwidth to avoid network bottlenecks. (Because the network is not controllable, is provided by the operator, uncontrollable, measuring attention is the system, not the network, if the system test, the ultimate measure is a network problem is unsolvable.)
Performance Testing concern two words: requests and responses. The normal sequence of requests and responses is, after the first send and receive
three, transaction response time
User time to complete a particular transaction (such as withdraw money transactions) required.
358 Principle: For general system, if the user clicks the button, the system can obtain a response within 3 seconds, the user is satisfied; If the system is to give a response within 5 seconds, the user can tolerate; 8 seconds if the system is answered, the user can not endure
four hits
HTTP user per submit requests to the web server
- the bigger hits, the greater the pressure on the server
clicks of the mouse does not refer to a "click" operation, as a "click", it is possible to send multiple servers request.
For example: the user clicks the login button, the page returned there three pictures, the click-through rate is 3 + 1 = 4. Traffic hits per second is called
the principle of the browser:
When a user accesses an HTML file (web page), the browser first to get the HTML file, and then parsing.
If the HTML file that contains information about pictures, videos, etc., the browser will visit again ** ** web server, in order to obtain these images, video files, and then organize HTML and images, video files up and displayed on the screen.
(Start time is a red X)
When there are many pictures, videos, and other non-text, full page display will make this more slowly, if this performance tuning, in fact, too many requests, we can consider whether the page images can be merged, reducing the request. Then consider this aspect of performance tuning.
Note: HTTP protocol is stateless, meaning that interaction between the browser and the server are independent of each other, Server is not aware of any requests from two Brower whether from the same page, or if regular order. Because, web control system in the upper HTTP protocol, from country Cookie, Session and other mechanisms to ensure the status of the request.
V. throughput
All users of any given one second amount of data obtained from the server, in bytes
throughput: throughput / transmission time
if the sufficient bandwidth, throughput increases as perfect CTR increases
six , resource utilization
generally refers to the process of conducting performance testing to monitor the resource AUT server, which server resources cpu, memory, disk, and network key performance counters, to focus on its utilization.
Seven, performance testing strategy
Benchmark
refers to the test environment to determine the future of the business models involved in important business to do a separate test.
The purpose is to obtain the performance indicators when the user performs a single, integrated multi-user concurrency and performance testing scenarios such as to provide reference analysis.
Concurrent testing
multi-user to perform an action while at the same time.
Objective: To examine the capacity of instantaneous pressure AUT
integrated scenario testing "can most realistic simulation of the actual production scenario"
① Under normal circumstances, need scripts for three or more virtual users into different groups perform different script. Note: Do not login script is generally added to the overall scene (because integrated scene usually lasts a long time (one hour), this time, all users running in a loop operation, and is not suitable for landing cycles)
② as 10 % of users perform browsing Home, 50% of users to execute the query orders, 40% of users to perform the booking operation.
Note: When a user performs an operation to set the proportion of overall scene, most users should do browse or query, do a small part of the commit operation.
Fatigue strength measurement
generally refers to a long-line testing integrated scenario, i.e. strength at a certain pressure, for a long time test, the test time is often 7 * 24 hours, 24 hours, 12 hours
memory leak detection
① memory leak: refers to when the system run-time, amount of memory has not been released in time, with the increase in running time, the memory occupied more and more, resulting in available physical memory is used up, the system is running slow or even put off (down) machine.
② memory leak detection: the use of the corresponding timer memory test software to monitor, observe compliance with the trend curve memory leaks; you can also use a special memory leak detection tools for testing.
Test data capacity
① test data of the AUT different capacities stored in the database, the performance of the reaction AUT.
② data capacity of the unit:
1024Byte = 1K; 1024K = 1M; 1024M = 1G; 1024G = 1T; 1024T = 1P
limit test
① also known as "Mogao test", that is, the use of performance testing, gradually increasing the pressure of the AUT, AUT test out the limits, such as maximum the number of users, the maximum throughput.
Increment test
certain period of time (e.g. 5s, 10s) loading a different number of virtual user performs every Test Point Test, the test point is incremented user stress loading test.
Objective: If all virtual users simultaneously load, there may be a sudden increase AUT resources, thereby affecting subsequent test data test points in interest, so the front can be a little slow down, incremental load virtual users.
Eight, the transaction
is a measure of performance of the server, you define transactions. To measure the transaction represents the end-user business processes or operations
Nine, scenes (Scenario)
① scene is a file for transactions that occur during each test session run based on performance requirements defined
② simulate the real environment, the health of the user.
How to test the parameters of the scene: take a principle - simulate the actual creation environment