Captain-TrippsandJon Staples 02269b4c00 sycl: add set_tensor_2d for faster tensor-split loading (#30358)
* sycl: add set_tensor_2d for faster tensor-split loading

Pack host rows into chunks of up to 64 MiB when destination rows are
contiguous, avoiding a separate upload call for each row. Keep the
existing per-row copy path for non-contiguous destinations.

On two Arc Pro B70s with gpt-oss-120b UD-Q4_K_XL, total llama-perplexity
runtime drops from 263-268 s to 114-115 s. A full-load readback check
verified 26,784,256 rows with no mismatches.

* sycl: batch 2D tensor uploads through shared staging slots

Implement set_tensor_2d to speed up tensor-split model loading by
packing rows into the existing pinned staging slots and uploading
each batch with a single device copy.

Share staging initialization with set_tensor and wait only when
reusing a slot, allowing CPU packing and device copies to overlap.

Fall back to per-row uploads for noncontiguous device rows,
oversized rows, or unavailable staging.

---------

Co-authored-by: Jon Staples <250234834+Captain-Tripps@users.noreply.github.com>
2026-10-26 16:12:25 +02:00
2026-10-23 07:46:53 -07:00
2026-06-12 15:53:26 +02:00
2026-10-17 02:11:56 +02:00
2026-02-02 08:38:55 +02:00

llama.cpp

llama

Quick start

A few options to get llama.cpp installed on your machine:

# curl
curl -LsSf https://llama.app/install.sh | sh

# powershell
irm https://llama.app/install.ps1 | iex

Once installed:

# Download and run a model directly from Hugging Face
llama cli -hf ggml-org/Qwen3.5-0.8B-GGUF

# Launch OpenAI-compatible API server
llama serve -hf ggml-org/Qwen3.5-0.8B-GGUF
VLM session with `llama cli` VLM session with llama cli Built-in web UI against `llama serve` running Qwen 3.6 Built-in web UI against llama serve

Description

The main goal of llama.cpp is to enable LLM (and VLM) inference with minimal setup and state-of-the-art performance on a wide range of hardware - locally and in the cloud.

  • Plain C/C++ implementation without any dependencies
  • Apple silicon is a first-class citizen - optimized via ARM NEON, Accelerate and Metal frameworks
  • AVX, AVX2, AVX512 and AMX support for x86 architectures
  • RVV, ZVFH, ZFH, ZICBOP and ZIHINTPAUSE support for RISC-V architectures
  • 1.5-bit, 2-bit, 3-bit, 4-bit, 5-bit, 6-bit, and 8-bit integer quantization for faster inference and reduced memory use
  • Custom CUDA kernels for running LLMs on NVIDIA GPUs (support for AMD GPUs via HIP and Moore Threads GPUs via MUSA)
  • Vulkan and SYCL backend support
  • CPU+GPU hybrid inference to partially accelerate models larger than the total VRAM capacity

The llama.cpp project is build on top of the ggml library.

Supported backends

Backend Target devices
BLAS All
BLIS All
CANN Ascend NPU
CUDA Nvidia GPU
HIP AMD GPU
Hexagon Snapdragon
IBM zDNN IBM Z & LinuxONE
MUSA Moore Threads GPU
Metal Apple Silicon
OpenCL Adreno GPU
OpenVINO [In Progress] Intel CPUs, GPUs, and NPUs
RPC All
SYCL Intel GPU
VirtGPU VirtGPU APIR
Vulkan GPU
WebGPU All
ZenDNN AMD CPU

Documentation

Tools

Development

Contributing

  • Contributors can open PRs
  • Collaborators will be invited based on contributions
  • Maintainers can push to branches in the llama.cpp repo and merge PRs into the master branch
  • Any help with managing issues, PRs and projects is very appreciated!
  • Read the CONTRIBUTING.md for more information

Acknowledgements

  • yhirose/cpp-httplib - Single-header HTTP server, used by llama-server - MIT license
  • nothings/stb - Single-header image format decoder, used by multimodal subsystem - Public domain
  • nlohmann/json - Single-header JSON library, used by various tools/examples - MIT License
  • mackron/miniaudio - Single-header audio format decoder, used by multimodal subsystem - Public domain
  • sheredom/subprocess.h - Single-header process launching solution for C and C++ - Public domain
Languages
C++ 56.2%
C 15.5%
Python 7.5%
Cuda 5.2%
TypeScript 4.4%
Other 11%