Using MKL Single Dynamic Library (mkl_rt)

[Towie__Ewan]

Hi,

I'm currently in the middle of migrating our software tools to using the Single Dynamic Library method for MKL, in replacement for directly linking the interface/threading layer libs. The main reason for this is to improve compatibility within Python environments.

I was aware that the runtime calls to define the interface/threading layers must be prior to any use of the MKL library, but in some cases it can be difficult to ensure that this is actually the case.

Worse still, there doesn't appear to be any way to determine if the MKL library has been initialised at the point of the runtime layer calls. It seems that if the MKL library has been used in any way prior to the layer calls, then they are simply ignored without any error/warning message or information.

For example, I had a case where the CNR mode had been defined prior to the calls to `mkl_set_interface_layer()` and `mkl_set_threading_layer()`. This meant these calls were ignored and the default interface/threading layers were initialised causing a seg fault later in the runtime.

Is there some way to check at the time of the call to define the layers if the MKL library has already been initialised?

Is it possible for the runtime layer commands to actually report if they are successful or not?

Thanks,

Ewan

For reference, I'm working on a:

- Linux x86_64 system

- MKL 2023.0

- GCC 9.5.0 compilers

- Mix of C/C++/Fortran code

[VarshaS_Intel]

Hi,

Thanks for posting in Intel Communities.

Could you please provide us with the sample reproducer code where you are observing such behavior which helps us to investigate more on your issue?

Thanks & Regards,

Varsha

[Gennady_F_Intel · Accepted solution]

Ewan,

explicitly, MKL has only mkl_set_interface_layer() and mkl_set_threading_layer() API to track if the requested interface layer has been set.

-Gennady

[Towie__Ewan]

Hi Gennady,

I haven't yet had the time to create a reproducer, although I do intend to.

I see from the documentation that these two method return an integer that is meant to represent the layer, but to clarify is this the layer that is currently set or the layer that it has been set to?

I'm trying to understand if there is a way to determine what layers are currently loaded, and how to check if the call was successful.

Thanks,

Ewan 

[VarshaS_Intel]

Hi,

We have not heard back from you. Could you please let us know if you have any other queries?

Thanks & Regards,

Varsha

[VarshaS_Intel]

Hi,

We have not heard back from you. Could you please let us know if you have any other queries?

Thanks & Regards,

Varsha

[VarshaS_Intel]

Hi,

mkl_set_interface_layer sets the interface layer for Intel oneMKL at run time. 

>>how to check if the call was successful

The function call returns -1 if the input parameter is incorrect or if the layer was not specified prior to the function call.

For more details regarding the setting of the interface/threading layer please go through the below link:

https://www.intel.com/content/www/us/en/docs/onemkl/developer-guide-windows/2023-2/dynamic-select-the-interface-and-threading-layer.html

Thanks & Regards,

Varsha

[VarshaS_Intel]

Hi,

We have not heard back from you. Could you please provide us with an update on your issue?

Thanks & Regards,

Varsha