Results for x.org server
The article was published in issue №3
This article describes several methods that the X Windows System interacts with hardware. The basic 2D hardware acceleration operations were examined using the EXA architecture as an example. Xorg was tested with x11perf version 1.5 to examine the performance.
Testing was carried out in 5 modes, i.e. with 2D hardware acceleration and without. The test results lead to the conclusion that the use of 2D hardware acceleration with EXA is justified when high-resolution images are to be used or it is necessary to reduce the load on the CPU.
Performance testing with disabled hardware interaction (2D GPU + dummy EXA) showed that the use of EXA significantly affects the test rate as 2D GPU + dummy EXA driver performs better compared to the modesetting driver only with a certain set of tests. It’s worth noting that the use of EXA with the DRM stack has to be studied further, since, in most cases, scaling, pixmap copying, solid color filling, and other operations are processed by the CPU when using the DRM stack with the EXA_MIXED_PIXMAPS option. In certain situations, the absence of this option can lead to many visual artifacts in the form of unrendered areas of the image when updating the framebuffer.