Same kernel but huge performance difference under linux and windows
Submitted by wan..@..il.com
Assigned to Zhigang Gong @gongzg
Description
I have managed to run my kernel on iGPU using beignet under Linux, great job. At the same time I test the performance of the same kernel under windows. Following is the performance result for my kernel (deblocking filter in HEVC), the performance (time in seconds) was not obtained by binding event to kernel launching in OpenCL as it also depends on the OpenCL runtime implementation under windows and linux, instead, it was obtained by the host side CPU profiling utilities.
H2D Kernel D2H
Linux 1.95, 3.89, 1.56 Windows 6.74, 0.85, 1.44
I am not sure whether you use the same compiler to the windows OpenCL compiler, but the performance of kernel differs too much under these two operation systems (but with the same hardware). Also the host to device copy take much more time on Windows, can not figure out why. Any hints?
my testbed configuration hardware:
CPU: i5-4570R, iGPU (HD5200)
OS: Win8.1
iGPU driver version 10.18.10.3960, latest INDE, Visual Studio 2013
Linux :14.04,
kernel 3.13
Beignet Release v1.0
gcc 4.8.3