DLT_LOG() is taking much time to return

[Somesh55]

Hello Team,

I am using DLT_LOG() api my application. And DLT_LOG() api is taking much longer time to return it is taking around 1.5 sec to return. This leads the issue which has performance requirement.

Environment:
Platform: SA8155 (Hypervisor QNX & Android)
OS: QNX

This is happening at around 20sec since boot up.
I have verified this after capturing the time before and after DLT_LOG() in my application.

Code Snippet:
clock_gettime(CLOCK_MONOTONIC, &tspec);
DLT_LOG();
clock_gettime(CLOCK_MONOTONIC, &tspec);

Also, I have added logs in dlt user library and found that dlt_initialize_socket_connection() is taking much time to finish.
https://github.com/COVESA/dlt-daemon/blob/master/src/lib/dlt_user.c#L284

After further analysis I have found that Semaphore is locked under dlt_initialize_socket_connection() and after processing ~1.5 sec it unlock. Mean while when DLT_LOG() is called then it is waiting for Semaphore unlock and delay can be seen at DLT_LOG() api.

Here's the trace info,
Thread 2 (housekeeper thread) is calling dlt_initialize_socket_connection() and semaphore lock is applied.
Thread 11 is calling DLT_LOG() and waiting for dlt_initialize_socket_connection() semaphore unlock.

Could you please share your feedback that how to change the semaphore in order to avoid this issue?

Thank you!

[Somesh55]

I wanted to attach the tracelog image but I could not able to attach.

[Somesh55]

Hello Team,

Could you please check and response. Thank you.

[Somesh55]

Hello Team,
Sorry, could you please check and share your feedback.
I required this information to fix in my project which I want to do soon.
It would be great if you could response.
Thank you.

[Somesh55]

Hello @minminlittleshrimp,
It would be great if you can support. Thank you.

[minminlittleshrimp]

Hello @Somesh55
So sorry not putting this into my tasklist.

I shall move this to issue tab later when I check for further info. Please next time can you just ping me in issue tab for more convenience for you so that we can provide you more efficient support.
Thanks

[minminlittleshrimp]

Hi @Somesh55
If you still interested, recently we found there deadlock global holding DLT_LOG from logging by housekeeping thread, this has been solved in v2.18.11
Regards