Trace Profiting: Some questions need to be answered

[137-zwq]

environment:skywalking10.1.0、java-agent9.3.0、elasticsearch7.10.2

Question 1: After creating the Trace Profiling task, I found that some API interfaces were unable to obtain the trace of the samples.
The operation is as follows:
Endpoint GET:/ system/role/list， There is no sampled data.

I found that there is already data in the link tracing, but during the task, the endpoint GET:/ The response time of system/ole/list is all less than 10ms.

Another analysis task, with the endpoint being GET:/ basic/homepage/warnList， The average response time is 280ms, which can be collected.

I found that the official documentation states that if the endpoint response time is less than 10ms, the trace analysis task cannot collect data. Is this the reason for this?

Question 2: If the first Trace Profiting task is not completed, the second task cannot be created. Is this the design?And the task still prompts for successful creation, but it does not exist in the task list.

Question 3:When conducting task analysis, an error message will be reported indicating a null pointer exception.Is this a bug?
I found that when using Elasticsearch storage, when clicking the analyze button and no results are found, the code returns null, and the code converts null to int type and reports an error. How should I handle it? Do I need to set the sequence to -1 when no results are found in the database?

[wu-sheng]

I found that the official documentation states that if the endpoint response time is less than 10ms, the trace analysis task cannot collect data. Is this the reason for this?

Yes, it is.

Question 2: If the first Trace Profiting task is not completed, the second task cannot be created. Is this the design?And the task still prompts for successful creation, but it does not exist in the task list.

Yes, it is by design. Because profiling has extra payload, your app may be impacted too much.

Question 3:When conducting task analysis, an error message will be reported indicating a null pointer exception.Is this a bug?

It could be, we are going to release 10.2 soon. Maybe you could try to upgrade and try new verssion.

[137-zwq]

Okay, thank you for your answer!