Valve's Mesa Developers Continue Tuning KHR_no_error For Saving CPU Cycles
Written by Michael Larabel in Mesa on 1 June 2017 at 09:22 AM EDT. 11 Comments
MESA --
Valve's developers working on the Mesa / Linux graphics driver stack continue tuning KHR_no_error for helping lower the CPU utilization in OpenGL bug-free games.

KHR_no_error allows not generating OpenGL errors to save some CPU resources but instead if issues are encountered there could be cases of undefined behavior. But for OpenGL bug-free games/applications, making use of KHR_no_error could free up some CPU resources and potentially allow the system to run in a lower power-state a bit longer.

The KHR_no_error support has been in mainline Mesa since April and users of Mesa Git can toggle it via MESA_NO_ERROR environment variable. Your mileage may vary though depending upon your CPU, GPU, and OpenGL workloads.

Since the initial support landed, Timothy Arceri and now Samuel Pitoiset (both of Valve) have continued finding additional areas to improve upon for conserving CPU resources when this no-error-reporting is enabled. Pitoiset has sent out a set of 21 patches for adding KHR_no_error coverage to more OpenGL functions. He found these while system profiling Dawn of War III, which will be released next week. With these 21 extra patches touching a few hundred lines of code, it can save a "few CPU cycles."

Dawn of War III OpenGL/Vulkan Linux benchmarks next week, but whether it will work on mainline Mesa Git next week is yet to be determined as first the ARB_bindless_texture work must land for RadeonSI to handle this game.
Related News
About The Author
Author picture

Michael Larabel is the principal author of Phoronix.com and founded the site in 2004 with a focus on enriching the Linux hardware experience. Michael has written more than 20,000 articles covering the state of Linux hardware support, Linux performance, graphics drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and OpenBenchmarking.org automated benchmarking software. He can be followed via Twitter or contacted via MichaelLarabel.com.

Popular News This Week