This is the 14th day of my participation in the November Gwen Challenge. Check out the event details: The last Gwen Challenge 2021

As a developer, I often hear terms like TPS and QPS without really knowing what they mean. Let’s make a summary of the concepts and usages of these nouns. This includes terms for performance testing and website statistics.

QPS

Refers to the number of requests processed by the system per second.

RT

Reaction time refers to the reaction time of a request

TPS

Number of transactions processed per second. A transaction is the process by which a client sends a request to the server and the server responds. Measure the ability of the system to handle transactions or transactions, i.e. the ability of the server to handle customer requests, the number of transactions handled per second, commonly used on LoadRunner, set up transactions, and then count how many defined transactions the system can successfully complete per unit of time.

CPU utilization

General performance test indicators, CPU usage less than 75% is appropriate

Load Server Load

Load refers to the number of processes that are being processed by the CPU and the number of processes that are waiting to be processed by the CPU within a specified period of time. In general testing, this metric is Load< number of CPU cores *2

The response time

Time required to respond to a request, response time = network response time + application response time = (N1+N2+N3+N4) +(A1+A2+A3) Average response time: the average time taken by all requests

For example, if there are 100 requests, 98 of them take 1ms and the other two take 100ms

Mean response time

(98 * 1 + 2 * 100) / 100.0 = 2.98ms, however, 2.98ms does not reflect the overall efficiency of the server, because 98 requests take only 1ms, extended to the percentile

percentile

Take response time for example, which means that 99% of requests are below this value, which is a better indicator of overall efficiency.

Number of concurrent users

Concurrency refers to the number of online users interacting with the server (making requests to the server) at the same time. The number of concurrent users C is calculated as nL/T

  • N: Indicates the number of users accessing the system every day
  • L: The time from login to logout of an online user
  • T: How long does the user spend on the system every day

Peak C1, the maximum number of concurrent requests, is calculated by C1=C+³√C

  • Maximum number of concurrent users: When the system load is equal to the maximum number of concurrent users, the overall system efficiency is the highest, no resources are wasted, and users do not need to wait
  • Maximum number of concurrent users: the system is constantly under load, while some users are processing and others are waiting within their maximum waiting time
Online users

Indicates the number of users accessing the system in a certain period of time. For example, multiple users are browsing web pages but do not make data requests to the server at the same time. The number of concurrent users must be separated from the number of concurrent users.

throughput

Amount of data transferred over the network (number of customer requests processed)

throughput

The unit of time (seconds/minutes/hours/days) indicates the amount of data successfully transferred on the network, such as requests/second or pages/second

clicks

Indicates the number of HTTP requests received by the Web Server.

Click rate

Number of HTTP requests submitted by users to the Web Server per second. Distinguish the number of mouse clicks: for example, if you request a Web page with three images, the number of clicks requested to the Web Server is 1+3=4, and one click of the mouse allows you to visit the Web page, with only one click

UV

Unique Visitors refers to the number of Visitors to a site at different IP addresses. During the same day, UV only records visitors with unique IP who enter the site for the first time, and does not count visitors who return to the site within the same day.

Number of unique visitors and number of unique IP addresses are two different concepts. The number of unique visitors may not be the same as the number of unique visitors.

On the same computer, you sign up for a new user, and your girlfriend signs up for a new user. At this point, the background of the website will record an independent IP, but at the same time will record two UV. On the same computer, you and your girlfriend are not registered, just browsing. The background will record 1 independent IP and 1 UV. Of course, no matter how many times a unique visitor accesses a single IP address in the same day, the background records only one time.

PV

Page views, or clicks, English PageView. Every user, every page opened is a PV. A website from the home page to the success of registration a total of three pages, respectively: home page, fill in the user name and password, registration success.

Every user successfully clicks register from the home page and completes the registration process, and the background will count the website and thus obtain 3 PV. IP+UV+PV, can reflect the traffic indicators of a website.

RV

Repeat Visitors Yesterday you came to read my article, and today you come again. You are an RV. Repeat visitors show how sticky the site is to the user, so you can estimate how high the RV of wechat will be.

TP

Page duration, English Time On Page

TS

Traffic source channel, English Traffic Sources, Baidu contributed 100 UV for you every day, the user directly input website contributed 10000 UV for you, wechat brings you 1000 UV every day, source channel you are an important basis for the analysis and summary of the follow-up focus on that.

PR value

PageRank is a method Google uses to measure the “importance” of a web page.