Intel® oneAPI Threading Building Blocks
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Turn off TBB Warning

erling_andersen
New Contributor I
738 Views

Hi

 

I understand why get this warning:

 

TBB Warning: The number of workers is currently limited to 3. The request for 7 workers is ignored. Further requests for more workers will be silently ignored until the limit changes.

 

But I do not want TBB print it out ever. How to turn it off?

 

The customers of our program would get very annoyed by this warning.

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6 Replies
NoorjahanSk_Intel
Moderator
705 Views

Hi,

Thanks for reaching out to us.

 

The warning is usually caused by either tbb::task_scheduler_init or tbb::task_arena when an explicit number of threads is requested.

Could you please provide a sample reproducer to work on it from our end?

 

Also please provide the below details:

Os & version

Compiler used

OneTBB version is being used.

 

Thanks & Regards,

Noorjahan.

 

 

erling_andersen
New Contributor I
699 Views
Below should be sufficient info. to reproduce it.
 
It also happens you try to set the number threads to a large number in the official OneAPI TBB
Version 2021.4.0 Build 20210924
(for Windows) supplied by you. I tried to set numworkers=128 on a 12 core Windows machine as follows:
 
arena = new tbb::task_arena (numworkers);
 
and got
 
TBB Warning: The number of workers is currently limited to 23. The request for 127 workers is ignored. Further requests for more workers will be silently ignored until the limit changes.
erling_andersen
New Contributor I
681 Views

Now I also located the source generating the warning

 

https://github.com/oneapi-src/oneTBB/search?q=The+number+of+workers+is+currently+limited

 

 

NoorjahanSk_Intel
Moderator
652 Views

Hi,


Thanks for providing the details.


Sorry for the inconvenience caused to you during the TBB warning.


We do not have any flag that can turn off the warning as of now.


If necessary you can raise a feature request if you have priority support, else you can potentially submit a request through GitHub.


Thanks & Regards,

Noorajahn.


NoorjahanSk_Intel
Moderator
611 Views

Hi,


Could you please let us know if you require any further assistance? If not then can we go ahead and close this thread?


Thanks & Regards,

Noorajahan.


NoorjahanSk_Intel
Moderator
514 Views

Hi,


I have not heard back from you, so I will close this inquiry now. If you need further assistance, please post a new question.


Thanks & Regards,

Noorjahan.


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