Intel GPU driver for Linux has been updated to increase performance 100 times, why?

The developers of graphics drivers for Intel Linux have released an update that improves ray tracing performance for Arc GPUs by a factor of 100. However, it is reported that this update actually fixed a coding mistake and was only able to achieve 1/100 of the original performance so far.

Intel's Open-Source Vulkan Driver For Ray-Tracing Gets 'Like A 100x Improvement' --Phoronix
https://www.phoronix.com/news/Intel-Vulkan-RT-100x-Improve

Coding Mistake Made Intel GPUs 100X Slower in Ray Tracing | Tom's Hardware
https://www.tomshardware.com/news/intel-gpu-100x-performance-ray-tracing

In August 2021, Intel announced the high-performance graphics brand 'Intel Arc'. The first-generation microarchitecture 'Alchemist' included in this Intel Arc is based on Xe-HPG , one of the instruction set architectures of discrete GPUs developed by Intel for the first time in decades.

Intel announces high-performance graphics brand 'Intel Arc', codename of next-generation architecture revealed-GIGAZINE

According to Linux-related news site Phoronix, Lionel Landwerlin, the developer of graphics drivers for Linux on Intel GPUs, has implemented a fix merged into the open source Intel Arc Alchemist driver.

However, there was actually only one line missing in the driver's code, which made it impossible to set up a temporary memory allocation task to use for Vulkan Ray Tracing work. Therefore, the data of Vulkan Ray Tracing was allocated to the slower system memory instead of the VRAM of the graphics board, and the performance was reduced to about 1/100 of the original. 'This fix (not a joke) would be an improvement that would improve Vulkan Ray Tracing 's performance by a factor of 100,' Landwerlin commented ironically.

As a result, by setting the flag of 'ANV_BO_ALLOC_LOCAL_MEM', VRAM was allocated to the work of Vulkan Ray Tracing, and the performance was improved 100 times. Version 22.2 of Mesa , which includes the fixed driver, will be branched in the next few days and will be delivered to end users by the end of August.

Hardware news site Tom's Hardware reminds us of the importance of good drivers to support hardware. Intel's discrete GPUs and drivers are certainly immature and Arc Alchemist's expected initial performance And actual performance may be far from what it is. Intel has shown in a recent official benchmark that its card is the winner when comparing the Arc A750 to NVIDIA's GeForce RTX 3060. It's unclear if the A750 was a rival to the GeForce RTX 3060 or if it was aiming for a higher position. '