Large SYCL Iris Xe kernel performance reduction between Windows Intel Display driver v31 and v32

[MikeDB]

Hi,

I have some SYCL kernels I've been optimizing to run on Iris Xe integrated GPU. I'm seeing a large performance reduction in these kernels when running with Intel display driver v32 compared with v31. I've reverted to v31 drivers once and tried again with a later v32 driver with similar results.

Intel display driver:

new version A 32.0.101.6079 Release date: September 26, 2024

previous v32 attempt Version B 32.0.101.5972 Release date: August 23, 2024

old version 31.0.101.5592 Release date: June 24, 2024

Processor 12th Gen Intel(R) Core(TM) i7-1260P, 2100 Mhz, 12 Core(s), 16 Logical Processor(s)

Microsoft Windows 11 Pro

Intel DPC++ 2024.2.1

I have two kernels A and B templated on differing parameters 1/2. These are the timings in ms for kernel runs using versions 31.0.101.5592 and  32.0.101.6079. The output results are identical between the two.

A1 12.88 11.15
A2 9.25 1.81

B1 4.32 3.88
B2 2.28 2.02
These are the performance stats reported by SYCL queue profiling. In the worst case, kernel A2 runs over 5x slower after upgrading to display driver v32.

Is this change in any way expected due to changes in this update?

Can Intel suggest any steps to try and diagnose the cause of this performance reduction and so I can tweak my kernels to get the old performance back? Can we expect similar fluctuations in SYCL kernel performance with future display driver updates?

Thanks for your help.

[Alex_Y_Intel]

We would need a reproducer and exact commands used to investigate further. 

[MikeDB]

I've reverted to the v31 Intel display driver which is the official Dell driver for my machine and the performance is fine again. I'll stick to official Dell drivers for now rather than installing the latest Intel drivers.

Thanks,