Nsight system error : Unified Memory cannot be traced on devices that don't support peer-to-peer transfers

Developer Tools Nsight Systems Profiling Linux Targets
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Hello, I’m profiling my cuda program with Nsight System 2023.4.4.
But when i got nsys-rep, i got error message “CUDA device 0: Unified Memory cannot be traced on devices that don’t support peer-to-peer transfers.Please verify that SLI/NVLink is functioning properly.” and “CUDA device 1: Unified Memory cannot be traced on devices that don’t support peer-to-peer transfers.Please verify that SLI/NVLink is functioning properly.”.
It says that my devices don’t support peer-to-peer transfer, so it cannot trace any more.

I think i’m already check all the requirements.
I use 2 NVIDIA GeForce RTX 3090 devices which are both 552.22 driver version, core i9 cpu, windows 10.
Also my cuda program is version 11.7.

When i check the peer-to-peer memory accessability by “cudaDeviceCanAccessPeer”, it return 1 which means my 3090 gpus can support p2p memory access.
Also i enable peer access by “cudaDeviceEnablePeerAccess”.

The nsys-rep shows many things but error messages above appear, so i cannot believe the results of nsys-rep.

Can anyone help me? Thanks a lot.

2

That’s a pretty old CUDA and Nsys with a pretty new driver, which shouldn’t be a problem, but might be worth updating your Nsys to 2024.4.

The only bad data you would have from this warning is that the UVM trace line would not be present and if you asked for UVM gpu or CPU page faults you would not get them. The rest of the data should be solid.