Additional Wait Time Affects Onload Time for Same URL

Problem description

The customer The customer has configured two tasks with the same URL, and the other tasks are the same, with only one difference. One has an Extra Wait Time of 5s, and the other has not set.

In the Element module, in the same time period, it is found that Onload Time has a large difference? What's the reason?

Problem analysis

(1) Check the scatter data and find that Configuration has Extra Wait Time for task A. Most of the Probe scatter details include Onload Time. On the other hand, task B has only one point (2022-09-14 12:03:30) with Onload Time.

(2) So in the Element module, what is displayed is the average value. Within the time period, the number of all Onload Time added together/points
task A: A large number of Probe have Onload Time, so the data looks normal.
task B: There is only one Probe and Onload Time. If you average it, the value will drop instantly.
So there is no problem with Tingyun's statistics.
(3) Why can’t Onload Time be received during the access process?
First of all, onload is most commonly used in Element, which is used to execute scripts after all content of the web page visually complete (including images, script files, CSS files, etc.).
The customer page does not trigger onload after loading, so there is no report display.
Viewed through the "Developer Tools" of the page, it is a method on the customer page that is not supported on Chrome 79. If there is a long enough time to wait for it to come back, you can receive this time, so after giving Extra Wait Time, most of the Probe will have Onload Time.

Summarize

Through the above points, let’s summarize a few points:

1. The Extra Wait Time will not affect Onload Time,
   2.onload event is Event triggered by the browser when the page ends. Whether it is triggered or not is related to the actual structure of the page.
2. There is only one point in the background check 14 task with Onload Time, 2022-09-14 12:03:30
   4.13 This task received a large amount of data Onload Time,
3. The Element module is an average of Onload Time within the time period, so the time points/total points of 13 tasks are averaged out in one go.
4. There is no problem with our data statistics.
5. The reason is that there is a problem with loading the customer page on the lower version, which sometimes fails to trigger onload event.
6. This reason is caused by the incompatibility of the customer page on the Chrome 79 version.

Solution

1. Customers are compatible with lower versions and make the screenshot method compatible with Chrome 79 version. Currently, the chrome versions of Tingyun network Probe Windows system are all version 79.
2. Use a Linux client. The Linux clients are all Chrome 90. However, currently only page monitoring can be used as much as possible. Other Task Types need to be tested in advance.

Related indicators

(1) onload event: onload is most commonly used in Element to execute scripts after all content of web page visually complete (including images, script files, CSS files, etc.).
The Tingyun network page task takes the receipt of this Event as the end condition. When the Event is received, it is judged that the task is over, Total Download Time=Onload Time.
(2) Additional Wait Time: The time to wait for delayed loading of content after the page is loaded. The Default value is 0, which means no waiting.
If this function is configured, after receiving onload event, wait again