The llama.cpp project released version b10456, which includes a critical fix for the SYCL backend in quantized copy kernel launches. The update adjusts thread and block counts to be proportional to the quantization size, effectively reducing under- and over-subscription issues.

  • Fixes thread/block count in quantized cpy kernel launches (PR #27160).
  • Throughput for the q4_0 -> f32 path on an Arc 70 increases from 20.21 GB/s to 158.19 GB/s.
  • Other quantization paths show flat performance uplifts.
  • Binaries are available for macOS, Linux, Windows, Android, and openEuler across CPU, CUDA, Vulkan, ROCm, OpenVINO, and SYCL backends.

This change significantly improves data transfer efficiency on Intel Arc GPUs using the SYCL backend, addressing a major performance bottleneck in quantized operations.