1. Page load time The time
from when the page starts to load to when the page onload event is triggered. Generally speaking, the onload trigger means that the CSS, JS, and image resources directly referenced by HTML have been fully loaded.
2. Total page load time
Total page load time refers to the time from the initial start of browsing until all elements are loaded, and there is still no network activity after 2 seconds.
0-2 seconds: The user experience is the best, with a score of 100.
2-8 seconds: The user can tolerate it. From the second second, every time it exceeds 1 second, 5 minutes are subtracted.
8-15 seconds: The user cannot bear it. From the second second, every More than 1 second minus 5 minutes
3. The first byte time The time
from the start of loading to the receipt of the first byte of data returned by the server. The time to reach the
standard = DNS resolution time + time to create a connection + SSL certification time + 100ms. Each time slower than the standard time 10ms minus 1 minute.
0-1 seconds: the best user experience
1-2 seconds: users can tolerate
2-3 seconds: users can't tolerate
4. Use long connections The
connection view shows the (keepalive) connections created during page loading, and the resources loaded by each connection.
5. DNS time The time required
for domain name resolution is
0-50 milliseconds, 100 minutes and
50-500 milliseconds. Generally, it may affect the user experience. Starting from 50 milliseconds, every 10 milliseconds will be subtracted by 2 minutes and
500 milliseconds. Serious impact? The user's web page experience starts from 50 milliseconds, and subtracts 2 minutes for every 10 milliseconds.
6. TCP time
The time for the client to establish a connection is
0-100 milliseconds, 100 minutes and
100-500 milliseconds. Generally, it may affect the user experience. Starting from 100 milliseconds, there is no increase of 10 milliseconds, minus 1 minute and
500 milliseconds, which seriously affects the user's web page experience. , starting from 100 milliseconds, every 10 milliseconds, minus 1
point Byte time score * 0.2 + long connection used * 0.1 + DNS time score * 0.2 + TCP time score * 0.2 + HTTP web page score * 0.1 9. Other measurement indicators The time from can be used to locate network problems. Network packet loss rate Definition : The current network packet loss statistics. Network Delay Definition : The delay of the current network. Includes RTTc and RTTs. RTTc user-to-probe transmission delay RTTs probe-to-server transmission delay Other indicators that can be associated Number of affected users The so-called affected refers to how many users are affected when a certain indicator of the service is relatively poor . pass through
This indicator can then be used to obtain the specific affected users.
The number of affected sites
is how many sites are affected when there is a problem with the network or the server. pass through
Simply speaking, the processing of a Web request includes the following steps:
(1) The client sends the request
(2) The webserver receives the request and processes it;
(3) The webserver obtains data from the DB;
(4) The webserver generates the user's object (page), returned to the user. The time from the beginning of sending the request to the client to the last byte is called the response time (the third step is not included in each request processing).
1. Transaction
2. Request response time
3. Transaction response time A
transaction may be composed of a series of requests. The response time of a transaction is mainly for users, which is a macro concept and is proposed to explain the business response time to users. For
example: the response time of an inter-bank withdrawal transaction is composed of a series of requests. The
transaction response time is a parameter that directly measures the performance of the system.
4. The number of concurrent users
Concurrency is generally divided into two
situations. One is concurrency in the strict sense,
that is, all users do the same thing or operation at the same time, which generally refers to doing the same type of business. For example, in the credit card approval business, a certain number of supporters submit the completed approval business at the same time; there is also a special case, that is, all users perform exactly the same operation, for example, in the credit card approval business, all users can apply together business, or modify the same record.
Another type of concurrency is broad scope concurrency. The difference between this concurrency and the previous concurrency is that although multiple users have issued requests or performed operations on the system, these requests or operations can be the same or different. For the whole system, there are still many users operating the system at the same time, so it also belongs to the category of concurrency.
It can be seen that the latter concurrency includes the former concurrency. And the latter kind of concurrency is closer to the actual usage of users, so for most systems, only a small number of users are "strictly concurrent". For WEB performance testing, these two concurrency situations generally need to be tested, and the usual practice is to perform concurrency testing in a strict sense first. User concurrency in the strict sense generally occurs in modules that are used
more frequently. Although the probability of occurrence is not very large, once a performance problem occurs, the consequences are likely to be fatal. Concurrency testing in the strict sense is often
associated , because exceptions encountered in concurrent functions are usually program problems, and this testing is also part of robustness and stability testing.
Number of concurrent users: There are 2 common misconceptions about the number of concurrent users.
A wrong view is to interpret the number of concurrent users as the total number of users using the system, on the grounds that these users may use the system at the same time; there is a more correct view that the number of online users is understood as the number of concurrent users. In fact, online users are not necessarily concurrent with other users. For example, users who are browsing web pages have no impact on the server. However, the number of online users is one of the main criteria for calculating the number of concurrent users.
5. Throughput
refers to the total amount of data transmitted on the network during a performance test
. Throughput/transmission time is the throughput rate.
6.tps
7. Hits PV
The number of HTTP requests submitted by users to the WEB server per second. This indicator is a unique indicator of WEB applications: WEB applications are in the "request-response" mode. Once a user sends an application, the server will process it once, so clicking is a WEB
application can The smallest unit of transactions processed. If each click is defined as a transaction, the CTR and TPS are a concept. It is easy to see that the higher the CTR, the greater the pressure on the server. The CTR is only a performance reference indicator, important is to analyze the impact of clicks. It should be noted that the click here does not refer to a single-click operation of the mouse, because in a single-click operation, the client may issue multiple HTTP requests to the server.
8. Resource utilization
Performance item command indicator
CPU limit vmstat when % When user+%sys exceeds 80%
Disk I/O limit Vmstat When %iowait exceeds 40% (AIX4.3.3 or later)
Apply disk limit Iostat When %tm_act exceeds 70%
Virtual memory space is less Lsps, -a when paging When the active rate of the space exceeds 70%,
the paging limit Iostat, stat virtual memory logical volume %tm_act exceeds 30% of the I/O (iostat), and the activated virtual memory rate exceeds 10 times the number of CPUs (vmstat).
from when the page starts to load to when the page onload event is triggered. Generally speaking, the onload trigger means that the CSS, JS, and image resources directly referenced by HTML have been fully loaded.
2. Total page load time
Total page load time refers to the time from the initial start of browsing until all elements are loaded, and there is still no network activity after 2 seconds.
0-2 seconds: The user experience is the best, with a score of 100.
2-8 seconds: The user can tolerate it. From the second second, every time it exceeds 1 second, 5 minutes are subtracted.
8-15 seconds: The user cannot bear it. From the second second, every More than 1 second minus 5 minutes
3. The first byte time The time
from the start of loading to the receipt of the first byte of data returned by the server. The time to reach the
standard = DNS resolution time + time to create a connection + SSL certification time + 100ms. Each time slower than the standard time 10ms minus 1 minute.
0-1 seconds: the best user experience
1-2 seconds: users can tolerate
2-3 seconds: users can't tolerate
4. Use long connections The
connection view shows the (keepalive) connections created during page loading, and the resources loaded by each connection.
5. DNS time The time required
for domain name resolution is
0-50 milliseconds, 100 minutes and
50-500 milliseconds. Generally, it may affect the user experience. Starting from 50 milliseconds, every 10 milliseconds will be subtracted by 2 minutes and
500 milliseconds. Serious impact? The user's web page experience starts from 50 milliseconds, and subtracts 2 minutes for every 10 milliseconds.
6. TCP time
The time for the client to establish a connection is
0-100 milliseconds, 100 minutes and
100-500 milliseconds. Generally, it may affect the user experience. Starting from 100 milliseconds, there is no increase of 10 milliseconds, minus 1 minute and
500 milliseconds, which seriously affects the user's web page experience. , starting from 100 milliseconds, every 10 milliseconds, minus 1
point Byte time score * 0.2 + long connection used * 0.1 + DNS time score * 0.2 + TCP time score * 0.2 + HTTP web page score * 0.1 9. Other measurement indicators The time from can be used to locate network problems. Network packet loss rate Definition : The current network packet loss statistics. Network Delay Definition : The delay of the current network. Includes RTTc and RTTs. RTTc user-to-probe transmission delay RTTs probe-to-server transmission delay Other indicators that can be associated Number of affected users The so-called affected refers to how many users are affected when a certain indicator of the service is relatively poor . pass through
This indicator can then be used to obtain the specific affected users.
The number of affected sites
is how many sites are affected when there is a problem with the network or the server. pass through
This indicator can then be used to obtain the specific affected sites.
Simply speaking, the processing of a Web request includes the following steps:
(1) The client sends the request
(2) The webserver receives the request and processes it;
(3) The webserver obtains data from the DB;
(4) The webserver generates the user's object (page), returned to the user. The time from the beginning of sending the request to the client to the last byte is called the response time (the third step is not included in each request processing).
1. Transaction
2. Request response time
3. Transaction response time A
transaction may be composed of a series of requests. The response time of a transaction is mainly for users, which is a macro concept and is proposed to explain the business response time to users. For
example: the response time of an inter-bank withdrawal transaction is composed of a series of requests. The
transaction response time is a parameter that directly measures the performance of the system.
4. The number of concurrent users
Concurrency is generally divided into two
situations. One is concurrency in the strict sense,
that is, all users do the same thing or operation at the same time, which generally refers to doing the same type of business. For example, in the credit card approval business, a certain number of supporters submit the completed approval business at the same time; there is also a special case, that is, all users perform exactly the same operation, for example, in the credit card approval business, all users can apply together business, or modify the same record.
Another type of concurrency is broad scope concurrency. The difference between this concurrency and the previous concurrency is that although multiple users have issued requests or performed operations on the system, these requests or operations can be the same or different. For the whole system, there are still many users operating the system at the same time, so it also belongs to the category of concurrency.
It can be seen that the latter concurrency includes the former concurrency. And the latter kind of concurrency is closer to the actual usage of users, so for most systems, only a small number of users are "strictly concurrent". For WEB performance testing, these two concurrency situations generally need to be tested, and the usual practice is to perform concurrency testing in a strict sense first. User concurrency in the strict sense generally occurs in modules that are used
more frequently. Although the probability of occurrence is not very large, once a performance problem occurs, the consequences are likely to be fatal. Concurrency testing in the strict sense is often
associated , because exceptions encountered in concurrent functions are usually program problems, and this testing is also part of robustness and stability testing.
Number of concurrent users: There are 2 common misconceptions about the number of concurrent users.
A wrong view is to interpret the number of concurrent users as the total number of users using the system, on the grounds that these users may use the system at the same time; there is a more correct view that the number of online users is understood as the number of concurrent users. In fact, online users are not necessarily concurrent with other users. For example, users who are browsing web pages have no impact on the server. However, the number of online users is one of the main criteria for calculating the number of concurrent users.
5. Throughput
refers to the total amount of data transmitted on the network during a performance test
. Throughput/transmission time is the throughput rate.
6.tps
7. Hits PV
The number of HTTP requests submitted by users to the WEB server per second. This indicator is a unique indicator of WEB applications: WEB applications are in the "request-response" mode. Once a user sends an application, the server will process it once, so clicking is a WEB
application can The smallest unit of transactions processed. If each click is defined as a transaction, the CTR and TPS are a concept. It is easy to see that the higher the CTR, the greater the pressure on the server. The CTR is only a performance reference indicator, important is to analyze the impact of clicks. It should be noted that the click here does not refer to a single-click operation of the mouse, because in a single-click operation, the client may issue multiple HTTP requests to the server.
8. Resource utilization
Performance item command indicator
CPU limit vmstat when % When user+%sys exceeds 80%
Disk I/O limit Vmstat When %iowait exceeds 40% (AIX4.3.3 or later)
Apply disk limit Iostat When %tm_act exceeds 70%
Virtual memory space is less Lsps, -a when paging When the active rate of the space exceeds 70%,
the paging limit Iostat, stat virtual memory logical volume %tm_act exceeds 30% of the I/O (iostat), and the activated virtual memory rate exceeds 10 times the number of CPUs (vmstat).
System failure Vmstat, sar page swap increases, CPU waits and runs the queue.
Reprinted: https://www.cnblogs.com/Javame/archive/2018/04/02/8690012.html