LLM inference in C/C++
Go to file
Daniel Bevenius ffba4f29e6
examples : add debug utility/example (#18464)
* examples : add debug utility/example

This commit introduces a new example named llama-debug which is a
utility that is intended to be used to assist with developing/debugging
a converted model.

The motivation for this utilitiy is to assist in model conversion work
to verify that the model produces the expected outputs. It is intended
to replace logits.cpp in examples/model-conversion.

Example usage:
```console
./build/bin/llama-debug \
    -m models/Qwen2.5-0.5B-Instruct.gguf \
    --prompt "Hello, my name is" \
    --save-logits
...
Model add_bos: false
Input prompt: "Hello, my name is"
Token ids (5):
Hello(9707) ,(11)  my(847)  name(829)  is(374)
Data saved to data/llamacpp-Qwen2.5-0.5B-Instruct.bin
Data saved to data/llamacpp-Qwen2.5-0.5B-Instruct.txt
Prompt saved to data/llamacpp-Qwen2.5-0.5B-Instruct-prompt.txt
Tokens saved to data/llamacpp-Qwen2.5-0.5B-Instruct-tokens.bin
```

For more details about the options available for this example, please
refer to examples/debug/README.md.

* throw runtime error instead of logging error

* remove params.warmup and enable the warmup/nowarmup option

* model-conversion : remove logits.cpp

This commit removes logits.cpp in favor of using llama-debug for
generating logits and embeddings.

* examples : remove model-conversion directory

This was missed in the previous commit.

* model-conversion : add support for saving prompt and token ids

This commit add support for storing the prompt and the token ids for the
prompt when running the original models.

The motivation for this is that this will allow us to compare the prompt
and the tokens generated for the prompt when verifing the converted
model. Currently it is possible that even if the same prompt is used
that the tokens generated are different if there is a difference in the
tokenization between the original and converted model which would
currently go unnoticed (the verification will most likely fail but it
might not be obvious why).

* squash! model-conversion : add support for saving prompt and token ids

fix pyright errors.

* model-conversion : add compare_tokens utility

This commit adds a script to compare token outputs between original and
converted models.

Example usage:
```console
(venv) $ ./scripts/utils/compare_tokens.py pytorch-gemma-3-270m-it llamacpp-gemma-3-270m-it-bf16

Comparing tokens between:
  Original : pytorch-gemma-3-270m-it (6 tokens)
  Converted: llamacpp-gemma-3-270m-it-bf16 (6 tokens)

 All 6 tokens match!
```
And there is a verbose flag that will also print out the prompts:
```console
(venv) $ ./scripts/utils/compare_tokens.py pytorch-gemma-3-270m-it llamacpp-gemma-3-270m-it-bf16 -v

Original model prompt (pytorch-gemma-3-270m-it):
  prompt: Hello, my name is
n_tokens: 6
token ids: 2, 9259, 236764, 1041, 1463, 563

Converted model prompt (llamacpp-gemma-3-270m-it-bf16):
  prompt: Hello, my name is
n_tokens: 6
token ids: 2, 9259, 236764, 1041, 1463, 563

Comparing tokens between:
  Original : pytorch-gemma-3-270m-it (6 tokens)
  Converted: llamacpp-gemma-3-270m-it-bf16 (6 tokens)

 All 6 tokens match!
```

* model-conversion : add token comparison to verifiction scripts

This commit add the calling of the compare_tokens function in
compare-logits.py and semantic_check.py to ensure that the token ids
that the tokenizers procoduce are the same before proceeding with
verifying the logits/embeddings.

Placing them in the existing scripts instead calling them separately
ensures that the token comparison is always done prior to the
logit/embedding verifications.

Follow up commit/pr could refactor the causal logits verification into
a single script instead of the two that exist now. This would reduce the
code and make it consistent with the embeddings verficiation which only
has a single script.

* debug : use llama_model_n_embd_out

This commit updates the debug example to use the new function
llama_model_n_embd_out instead of llama_model_n_embd.

The motivation for this change is to support late interation retriever
models, like LFM2-ColBert-350M, where the output embeddings are down
projected to a lower dimension.

* debug : add print_usage function

This commit adds a print_usage function that is passed to the
common_params_parse.

The motivation for this is that this enables a specific usage message
which will be printed after all the options, for example:
```console
example usage:

  Print tensors:

  ./build/bin/llama-debug -m model.gguf -p "Hello my name is" --verbose

  The tensors to be printed can be filtered with --tensor-filter option.

  Save logits/embeddings:

  ./build/bin/llama-debug -m model.gguf -p "Hello my name is" --save-logits

  Add --embedding to save embeddings
```
2026-01-07 10:42:19 +01:00
.devops docker : add CUDA 13.1 image build (#18441) 2025-12-30 22:28:53 +01:00
.gemini contributing: tighten AI usage policy (#18388) 2025-12-29 16:01:32 +01:00
.github ci : init git lfs in every build for RISC-V (#18590) 2026-01-05 02:18:33 +01:00
benches/dgx-spark benches : add eval results (#17139) 2025-11-10 10:44:10 +02:00
ci sampling : add support for backend sampling (#17004) 2026-01-04 22:22:16 +02:00
cmake cmake : simplify build info detection using standard variables (#17423) 2025-12-04 12:42:13 +02:00
common examples : add debug utility/example (#18464) 2026-01-07 10:42:19 +01:00
docs ggml webgpu: add CEIL operation support (#18605) 2026-01-05 11:38:57 -08:00
examples examples : add debug utility/example (#18464) 2026-01-07 10:42:19 +01:00
ggml CANN: Fix rename for get_env (#18652) 2026-01-07 16:11:31 +08:00
gguf-py gguf-py : add requests to dependencies (#18629) 2026-01-06 08:56:38 +01:00
grammars docs : document that JSON Schema is not available to model when using response_format (#18492) 2025-12-30 15:13:49 -06:00
include model : add LFM2-ColBert-350M (#18607) 2026-01-05 19:52:56 +01:00
licenses cmake : enable curl by default (#12761) 2025-04-07 13:35:19 +02:00
media media : add transparent icon svg and png [no ci] (#15891) 2025-09-10 14:51:28 +03:00
models common : default content to an empty string (#18485) 2025-12-30 12:00:57 -06:00
pocs ggml : move AMX to the CPU backend (#10570) 2024-11-29 21:54:58 +01:00
requirements convert : update transformers requirements (#16866) 2025-10-30 23:15:03 +01:00
scripts Hexagon add support for f16/f32 flash attention, scale, set-rows and improve f16/32 matmul (#18611) 2026-01-06 17:38:29 -08:00
src llama-params-fit: fix last devices with low VRAM (#18494) 2026-01-06 20:02:30 +01:00
tests arg: use CSV escape style for multiple-value args (#18643) 2026-01-06 17:51:08 +01:00
tools mtmd: mtmd_audio_streaming_istft (#18645) 2026-01-06 21:00:29 +01:00
vendor cmake: correct scope - link ws2_32 for MinGW/w64devkit builds in cpp-httplib (#17972) 2025-12-13 12:46:36 +01:00
.clang-format fix: apply clang-format to CUDA macros (#16017) 2025-09-16 08:59:19 +02:00
.clang-tidy clang-tidy : disable warning about performance enum size (#16127) 2025-09-22 19:57:46 +02:00
.dockerignore ci : fix docker build number and tag name (#9638) 2024-09-25 17:26:01 +02:00
.ecrc common : Update stb_image.h to latest version (#9161) 2024-08-27 08:58:50 +03:00
.editorconfig editorconfig : ignore benches/ (#17140) 2025-11-10 12:17:19 +02:00
.flake8 llama : move end-user examples to tools directory (#13249) 2025-05-02 20:27:13 +02:00
.gitignore vulkan: faster q6_k matmul (#17813) 2025-12-14 08:29:37 +01:00
.gitmodules ggml : remove kompute backend (#14501) 2025-07-03 07:48:32 +03:00
.pre-commit-config.yaml convert.py : add python logging instead of print() (#6511) 2024-05-03 22:36:41 +03:00
AGENTS.md contributing: tighten AI usage policy (#18388) 2025-12-29 16:01:32 +01:00
AUTHORS authors : update (#12271) 2025-03-08 18:26:00 +02:00
CLAUDE.md contributing: tighten AI usage policy (#18388) 2025-12-29 16:01:32 +01:00
CMakeLists.txt build : move _WIN32_WINNT definition to headers (#17736) 2025-12-04 07:04:02 +01:00
CMakePresets.json cmake : Add CMake presets for Linux and GCC (#14656) 2025-07-13 08:12:36 +03:00
CODEOWNERS llama.android : Rewrite Android binding (w/o cpu_features dep) (#17413) 2025-12-17 10:14:47 +02:00
CONTRIBUTING.md contributing: tighten AI usage policy (#18388) 2025-12-29 16:01:32 +01:00
LICENSE license : update copyright notice + add AUTHORS (#6405) 2024-04-09 09:23:19 +03:00
Makefile make : remove make in favor of CMake (#15449) 2025-08-20 13:31:16 +03:00
README.md llama.android : Rewrite Android binding (w/o cpu_features dep) (#17413) 2025-12-17 10:14:47 +02:00
SECURITY.md security : add collaborator guidance (#18081) 2025-12-16 11:17:11 +02:00
build-xcframework.sh cmake : move OpenSSL linking to vendor/cpp-httplib (#17177) 2025-11-12 12:32:50 +01:00
convert_hf_to_gguf.py model : add LFM2-ColBert-350M (#18607) 2026-01-05 19:52:56 +01:00
convert_hf_to_gguf_update.py model: support youtu-vl model (#18479) 2026-01-01 19:25:54 +01:00
convert_llama_ggml_to_gguf.py py : fix wrong input type for raw_dtype in ggml to gguf scripts (#8928) 2024-08-16 13:36:30 +03:00
convert_lora_to_gguf.py convert : allow quantizing lora again (#17453) 2025-11-24 15:50:55 +01:00
flake.lock flake.lock: Update (#10470) 2024-11-24 08:03:25 -08:00
flake.nix fix(nix): remove non-functional llama-cpp cachix cache from flake.nix (#15295) 2025-08-13 11:21:31 -07:00
mypy.ini convert : partially revert PR #4818 (#5041) 2024-01-20 18:14:18 -05:00
poetry.lock build(python): Package scripts with pip-0517 compliance 2024-07-04 15:39:13 +00:00
pyproject.toml gguf-py : avoid requiring pyside6 for other scripts (#13036) 2025-05-05 22:27:31 -04:00
pyrightconfig.json model-conversion : use CONVERTED_MODEL value for converted model [no ci] (#17984) 2025-12-13 08:34:26 +01:00
requirements.txt `tool-call`: fix Qwen 2.5 Coder support, add micro benchmarks, support trigger patterns for lazy grammars (#12034) 2025-03-05 13:05:13 +00:00

README.md

llama.cpp

llama

License: MIT Release Server

Manifesto / ggml / ops

LLM inference in C/C++

Recent API changes

Hot topics


Quick start

Getting started with llama.cpp is straightforward. Here are several ways to install it on your machine:

Once installed, you'll need a model to work with. Head to the Obtaining and quantizing models section to learn more.

Example command:

# Use a local model file
llama-cli -m my_model.gguf

# Or download and run a model directly from Hugging Face
llama-cli -hf ggml-org/gemma-3-1b-it-GGUF

# Launch OpenAI-compatible API server
llama-server -hf ggml-org/gemma-3-1b-it-GGUF

Description

The main goal of llama.cpp is to enable LLM 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 the main playground for developing new features for the ggml library.

Models

Typically finetunes of the base models below are supported as well.

Instructions for adding support for new models: HOWTO-add-model.md

Text-only

Multimodal

Bindings
UIs

(to have a project listed here, it should clearly state that it depends on llama.cpp)

Tools
  • akx/ggify download PyTorch models from HuggingFace Hub and convert them to GGML
  • akx/ollama-dl download models from the Ollama library to be used directly with llama.cpp
  • crashr/gppm launch llama.cpp instances utilizing NVIDIA Tesla P40 or P100 GPUs with reduced idle power consumption
  • gpustack/gguf-parser - review/check the GGUF file and estimate the memory usage
  • Styled Lines (proprietary licensed, async wrapper of inference part for game development in Unity3d with pre-built Mobile and Web platform wrappers and a model example)
  • unslothai/unsloth 🦥 exports/saves fine-tuned and trained models to GGUF (Apache-2.0)
Infrastructure
  • Paddler - Open-source LLMOps platform for hosting and scaling AI in your own infrastructure
  • GPUStack - Manage GPU clusters for running LLMs
  • llama_cpp_canister - llama.cpp as a smart contract on the Internet Computer, using WebAssembly
  • llama-swap - transparent proxy that adds automatic model switching with llama-server
  • Kalavai - Crowdsource end to end LLM deployment at any scale
  • llmaz - ☸️ Easy, advanced inference platform for large language models on Kubernetes.
Games
  • Lucy's Labyrinth - A simple maze game where agents controlled by an AI model will try to trick you.

Supported backends

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

Obtaining and quantizing models

The Hugging Face platform hosts a number of LLMs compatible with llama.cpp:

You can either manually download the GGUF file or directly use any llama.cpp-compatible models from Hugging Face or other model hosting sites, such as ModelScope, by using this CLI argument: -hf <user>/<model>[:quant]. For example:

llama-cli -hf ggml-org/gemma-3-1b-it-GGUF

By default, the CLI would download from Hugging Face, you can switch to other options with the environment variable MODEL_ENDPOINT. For example, you may opt to downloading model checkpoints from ModelScope or other model sharing communities by setting the environment variable, e.g. MODEL_ENDPOINT=https://www.modelscope.cn/.

After downloading a model, use the CLI tools to run it locally - see below.

llama.cpp requires the model to be stored in the GGUF file format. Models in other data formats can be converted to GGUF using the convert_*.py Python scripts in this repo.

The Hugging Face platform provides a variety of online tools for converting, quantizing and hosting models with llama.cpp:

To learn more about model quantization, read this documentation

llama-cli

A CLI tool for accessing and experimenting with most of llama.cpp's functionality.

  • Run in conversation mode

    Models with a built-in chat template will automatically activate conversation mode. If this doesn't occur, you can manually enable it by adding -cnv and specifying a suitable chat template with --chat-template NAME

    llama-cli -m model.gguf
    
    # > hi, who are you?
    # Hi there! I'm your helpful assistant! I'm an AI-powered chatbot designed to assist and provide information to users like you. I'm here to help answer your questions, provide guidance, and offer support on a wide range of topics. I'm a friendly and knowledgeable AI, and I'm always happy to help with anything you need. What's on your mind, and how can I assist you today?
    #
    # > what is 1+1?
    # Easy peasy! The answer to 1+1 is... 2!
    
  • Run in conversation mode with custom chat template
    # use the "chatml" template (use -h to see the list of supported templates)
    llama-cli -m model.gguf -cnv --chat-template chatml
    
    # use a custom template
    llama-cli -m model.gguf -cnv --in-prefix 'User: ' --reverse-prompt 'User:'
    
  • Constrain the output with a custom grammar
    llama-cli -m model.gguf -n 256 --grammar-file grammars/json.gbnf -p 'Request: schedule a call at 8pm; Command:'
    
    # {"appointmentTime": "8pm", "appointmentDetails": "schedule a a call"}
    

    The grammars/ folder contains a handful of sample grammars. To write your own, check out the GBNF Guide.

    For authoring more complex JSON grammars, check out https://grammar.intrinsiclabs.ai/

llama-server

A lightweight, OpenAI API compatible, HTTP server for serving LLMs.

  • Start a local HTTP server with default configuration on port 8080
    llama-server -m model.gguf --port 8080
    
    # Basic web UI can be accessed via browser: http://localhost:8080
    # Chat completion endpoint: http://localhost:8080/v1/chat/completions
    
  • Support multiple-users and parallel decoding
    # up to 4 concurrent requests, each with 4096 max context
    llama-server -m model.gguf -c 16384 -np 4
    
  • Enable speculative decoding
    # the draft.gguf model should be a small variant of the target model.gguf
    llama-server -m model.gguf -md draft.gguf
    
  • Serve an embedding model
    # use the /embedding endpoint
    llama-server -m model.gguf --embedding --pooling cls -ub 8192
    
  • Serve a reranking model
    # use the /reranking endpoint
    llama-server -m model.gguf --reranking
    
  • Constrain all outputs with a grammar
    # custom grammar
    llama-server -m model.gguf --grammar-file grammar.gbnf
    
    # JSON
    llama-server -m model.gguf --grammar-file grammars/json.gbnf
    

llama-perplexity

A tool for measuring the perplexity 1 (and other quality metrics) of a model over a given text.

  • Measure the perplexity over a text file
    llama-perplexity -m model.gguf -f file.txt
    
    # [1]15.2701,[2]5.4007,[3]5.3073,[4]6.2965,[5]5.8940,[6]5.6096,[7]5.7942,[8]4.9297, ...
    # Final estimate: PPL = 5.4007 +/- 0.67339
    
  • Measure KL divergence
    # TODO
    

llama-bench

Benchmark the performance of the inference for various parameters.

  • Run default benchmark
    llama-bench -m model.gguf
    
    # Output:
    # | model               |       size |     params | backend    | threads |          test |                  t/s |
    # | ------------------- | ---------: | ---------: | ---------- | ------: | ------------: | -------------------: |
    # | qwen2 1.5B Q4_0     | 885.97 MiB |     1.54 B | Metal,BLAS |      16 |         pp512 |      5765.41 ± 20.55 |
    # | qwen2 1.5B Q4_0     | 885.97 MiB |     1.54 B | Metal,BLAS |      16 |         tg128 |        197.71 ± 0.81 |
    #
    # build: 3e0ba0e60 (4229)
    

llama-run

A comprehensive example for running llama.cpp models. Useful for inferencing. Used with RamaLama 2.

  • Run a model with a specific prompt (by default it's pulled from Ollama registry)
    llama-run granite-code
    

llama-simple

A minimal example for implementing apps with llama.cpp. Useful for developers.

  • Basic text completion
    llama-simple -m model.gguf
    
    # Hello my name is Kaitlyn and I am a 16 year old girl. I am a junior in high school and I am currently taking a class called "The Art of
    

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!
  • See good first issues for tasks suitable for first contributions
  • Read the CONTRIBUTING.md for more information
  • Make sure to read this: Inference at the edge
  • A bit of backstory for those who are interested: Changelog podcast

Other documentation

Development documentation

Seminal papers and background on the models

If your issue is with model generation quality, then please at least scan the following links and papers to understand the limitations of LLaMA models. This is especially important when choosing an appropriate model size and appreciating both the significant and subtle differences between LLaMA models and ChatGPT:

XCFramework

The XCFramework is a precompiled version of the library for iOS, visionOS, tvOS, and macOS. It can be used in Swift projects without the need to compile the library from source. For example:

// swift-tools-version: 5.10
// The swift-tools-version declares the minimum version of Swift required to build this package.

import PackageDescription

let package = Package(
    name: "MyLlamaPackage",
    targets: [
        .executableTarget(
            name: "MyLlamaPackage",
            dependencies: [
                "LlamaFramework"
            ]),
        .binaryTarget(
            name: "LlamaFramework",
            url: "https://github.com/ggml-org/llama.cpp/releases/download/b5046/llama-b5046-xcframework.zip",
            checksum: "c19be78b5f00d8d29a25da41042cb7afa094cbf6280a225abe614b03b20029ab"
        )
    ]
)

The above example is using an intermediate build b5046 of the library. This can be modified to use a different version by changing the URL and checksum.

Completions

Command-line completion is available for some environments.

Bash Completion

$ build/bin/llama-cli --completion-bash > ~/.llama-completion.bash
$ source ~/.llama-completion.bash

Optionally this can be added to your .bashrc or .bash_profile to load it automatically. For example:

$ echo "source ~/.llama-completion.bash" >> ~/.bashrc

Dependencies

  • yhirose/cpp-httplib - Single-header HTTP server, used by llama-server - MIT license
  • stb-image - Single-header image format decoder, used by multimodal subsystem - Public domain
  • nlohmann/json - Single-header JSON library, used by various tools/examples - MIT License
  • minja - Minimal Jinja parser in C++, used by various tools/examples - MIT License
  • linenoise.cpp - C++ library that provides readline-like line editing capabilities, used by llama-run - BSD 2-Clause License
  • curl - Client-side URL transfer library, used by various tools/examples - CURL License
  • miniaudio.h - Single-header audio format decoder, used by multimodal subsystem - Public domain
  • subprocess.h - Single-header process launching solution for C and C++ - Public domain