InfiniCCL

InfiniCCL is a unified, cross-platform collective communication library designed to provide a unified interface for distributed deep learning and high-performance computing workloads across heterogeneous hardware architectures.

Prerequisites

Software Requirements

• C++17-compatible compiler

• CMake ≥ 3.18

• Python ≥ 3.10

  • Earlier versions MAY work but are not guaranteed

• Involved Hardware-specific SDKs (e.g. CUDA Toolkit)

• Involved Backend Libraries (e.g., OpenMPI, NCCL)

System Configuration

The participating nodes must meet the following requirements:

• Network connectivity between all nodes

• Passwordless SSH access

• Consistent library and binary paths across the cluster (e.g., shared filesystem such as NFS).

  • Note: Using inconsistent file paths across nodes has not yet been fully validated and may cause runtime failures during orchestration.

Key Features

• Platform Agnostic: NCCL‑like, unified C API for all supported platforms.
• Heterogeneous Communication: Supports communication operations across different platforms and accelerators.
• Platform Auto-Detection: Automatically detects the underlying hardware without manual specification.
• Smart Orchestration: Includes icclrun, a lightweight launcher for automated multi-node building, installation, and execution.

Building and Installation

InfiniCCL can be built either manually with CMake or using the provided build.sh script for a single‑command, environment‑aware installation. Currently InfiniCCL only offers install-from-source option.

To start, download InfiniCCL using git:

# Clone the repository
git clone https://github.com/InfiniTensor/InfiniCCL.git
cd InfiniCCL

There are two methods to build InfiniCCL.

Method 1 - Quick Build with build.sh (Recommended)

# Give execute permission to the script
chmod +x ./scripts/build.sh

# Build and install to default location (~/.infini)
./scripts/build.sh

To specify a custom install path (e.g., NFS shared directory)

INSTALL_PREFIX=/nfs/shared/infini ./scripts/build.sh

To set any CMake flag or option, simply add it after the script (See the end of this section for all the available options)

# For instance, explicitly turn on `NCCL`
./scripts/build.sh -DWITH_NCCL=ON

After the script completes, you will see output similar to:

========================================================
 Starting InfiniCCL Build
 Build Directory:  build
 Install Prefix:   /nfs/shared/infini
========================================================
-- No backend specified. Defaulting to WITH_OMPI=ON
-- Auto-detecting available devices...
-- Auto-detected NVIDIA environment.
-- InfiniCCL Config: Devices [cpu, nvidia] | Backends [ompi]
...
-- Installing: /nfs/shared/infini/lib/libinfiniccl.so
...
========================================================
 Build and Install Finished!
 Binaries:  /nfs/shared/infini/bin
 Libraries: /nfs/shared/infini/lib
 Headers:   /nfs/shared/infini/include
========================================================
 NOTE: If this is your first install, run: source ~/.bashrc
 You can now run 'icclrun' from anywhere.

Note: Running source ~/.bashrc (or restarting your terminal) is required only once to add icclrun to your PATH.

---

Method 2 - Manual Build with CMake

InfiniCCL can be built and installed manually.

# Build and Install InfiniCCL
mkdir build && cd build
cmake .. -DCMAKE_INSTALL_PREFIX=/path/to/install [options]
cmake --build . -j $(nproc)
cmake --install .

# Configure the Enviroment Variables
# It is recommended to add these to your `~/.bashrc` for persistence.
export INFINICCL_ROOT="/path/to/InfiniCCL"
export PATH="/path/to/install/bin:$PATH"
export LD_LIBRARY_PATH="/path/to/install/lib:$LD_LIBRARY_PATH"

Example Configurations: NVIDIA + OpenMPI

cmake .. -DWITH_NVIDIA=ON -DWITH_OMPI=ON

---

📋 Full list of CMake options (Click to expand)

InfiniCCL‑Specific Options

Option	Description	Default
Device (Hardware) Options
WITH_NVIDIA	Enable NVIDIA GPU support	OFF
WITH_METAX	Enable MetaX GPU support	OFF
WITH_CPU	CPU support (always enabled)	ON (internal, not user‑settable)
Backend (Communication) Options
WITH_OMPI	Enable OpenMPI backend	ON if no backend specified, otherwise OFF
WITH_NCCL	Enable NCCL backend	OFF
Miscellaneous
AUTO_DETECT_DEVICES	Automatically detect available devices and enable corresponding support	ON
BUILD_EXAMPLES	Build internal example programs	ON

Standard CMake Options (not InfiniCCL‑specific)

These options are available in any CMake project and can be passed during configuration:

Option	Description	Typical Default
CMAKE_INSTALL_PREFIX	Installation directory	/usr/local (set via -DCMAKE_INSTALL_PREFIX=... or environment)
CMAKE_BUILD_TYPE	Build type (Release, Debug, RelWithDebInfo, MinSizeRel)	(empty, but build.sh sets Release)

Notes:

• AUTO_DETECT_DEVICES overrides device options like WITH_NVIDIA when detection succeeds.

Using the Library

To compile and execute any program that uses InfiniCCL, we can simply use icclrun from a single node to launch, compile, and execute the program across a cluster.

To achieve this, a cluster.yaml is required to be filled. This is the configuration file for icclrun. examples/cluster.yaml is an example template.

After having a successful build and a complete cluster.yaml, we are ready for compiling and executing a distributed program across the cluster.

1. Run Internal Examples

To run an internal example program (e.g., examples/all_reduce.cc), just run:

# Build and run the executable across the cluster based on the config specified in your `cluster.yaml`
icclrun --config [path-to-your-cluster.yaml] --build all_reduce [program args]

• --config / -c : Path to the cluster YAML file.
• --build : Instructs icclrun to compile the library on each node before execution. If omitted, icclrun assumes the library is already installed at a consistent location.

The executable (e.g., all_reduce) and its arguments follow the options.

For more details, run:

icclrun --help

If everything is correctly set up, the example program should have just been launched and executed across the cluster you specified in cluster.yaml!

2. Run a Custom User Program

InfiniCCL does not yet provide a CMake config package (e.g., find_package(InfiniCCL)). Until then, the recommended way to link your own programs is to:

1. Set an environment variable INFINICCL_INSTALL pointing to the InfiniCCL installation directory (e.g., ~/.infini or a shared NFS path), and/or set the installed library path to LD_LIBRARY_PATH.

2. Link directly to the library, headers, and required dependencies (MPI, GPU runtime).

Within the program, just include:

#include <infiniccl/infiniccl.h>

Minimal CMakeLists.txt Example

cmake_minimum_required(VERSION 3.18)
project(UserApp LANGUAGES CXX)

# Path to InfiniCCL installation (set via environment)
set(INFINI_INSTALL_DIR $ENV{INFINICCL_INSTALL})

# Your application
add_executable(app main.cc)

# Direct linking to InfiniCCL
target_include_directories(app PRIVATE "${INFINI_INSTALL_DIR}/include")
target_link_libraries(app 
    PRIVATE 
    "${INFINI_INSTALL_DIR}/lib/libinfiniccl.so" 
    # other necessary libraries
    # ...
)

# RPATH to find `libinfiniccl.so` at runtime
set_target_properties(app PROPERTIES 
    BUILD_WITH_INSTALL_RPATH TRUE
    INSTALL_RPATH "${INFINI_INSTALL_DIR}/lib"
)

Then build and run with icclrun similar to internal examples:

icclrun --config [path-to-your-cluster.yaml] --build app [program args]

If You are not using CMake, you can compile and link the program manually similar to other dependencies, for instance with these options:

-I${INFINI_INSTALL}/include \
-L${INFINI_INSTALL}/lib \
-Wl,-rpath,${INFINI_INSTALL}/lib \
-linfiniccl \

If without -Wl, -rpath:

export LD_LIBRARY_PATH=${INFINI_INSTALL}/lib:$LD_LIBRARY_PATH

Supported Platforms and Backends

📋 Supported runtime device platforms (Click to expand)

Platform	Support Level	Notes
CPU	Partial	Runtime available, but no pure CPU collective operations yet. Planned for future releases.
NVIDIA	Full	Requires CUDA Toolkit.
MetaX	Full	Requires MACA SDK and MACA_PATH (default /opt/maca) to be set.

📋 Supported communication backends (Click to expand)

Backend	Support Level	Required CMake Option	Dependencies
OpenMPI	Full	WITH_OMPI=ON	The default backend. Requires the OpenMPI development package.

License

InfiniCCL is distributed under the LICENSE file in the root of the repository.

Contributing

Contributions are welcome! Please refer to the contribution guidelines in CONTRIBUTING.md.