Metall (memory allocator for persistent memory)

Provides rich memory allocation interfaces for C++ applications that use persistent memory devices to persistently store heap data on such devices.
Creates files in persistent memory and maps them into virtual memory space so that users can access the mapped region just as normal memory regions allocated in DRAM.
To provide persistent memory allocation, Metall employs concepts and APIs developed by Boost.Interprocess.
Supports multi-threa
Also provides a space-efficient snapshot/versioning leveraging reflink copy mechanism in filesystem. In case reflink is not supported, Metall automatically falls back to regular copy.

Getting Started

Install and Build

Metall consists of only header files and requires some header files in Boost C++ Libraries.

Metall is available at: https://github.com/LLNL/metall.

All core files exist under metall/include/metall/.

To build your program with Metall, all you have to do is just setting include paths such as '-I' or CPLUS_INCLUDE_PATH.

For example,

g++ -std=c++17 -lstdc++fs your_program.cpp -I/path/to/metall/include -I/path/to/boost/include

Note GCC requires linking stdc++fs to use the Filesystem library in C++17.

Install Using Spack

Metall package is also available on Spack.

To install Metall using Spack, type spack install metall.

As Metall requires Boost C++ Libraries, Spack also installs a proper (latest) version of Boost C++ Libraries automatically, if needed.

As Spack's load command configures environmental values properly, one can avoid specifying include paths to build a program with Metall. For instance:

spack load metall
g++ -std=c++17 -lstdc++fs your_program.cpp

Required to Build Metall

GCC 8.1 or more.
Boost C++ Libraries 1.64 or more (build is not required; needs only their header files).

Unofficial Support For Clang

Clang can be used instead of GCC to build Metall. However, we haven't tested it intensively. Also, Boost C++ Libraries 1.69 or more may be required if one wants to build Metall with Clang + CUDA.

Documentation

Full documentation is available.

Generate API document using Doxygen

A Doxygen configuration file is here.

To generate API document:

cd metall
mkdir build_doc
cd build_doc
doxygen ../docs/Doxyfile.in

Publication

Metall: A Persistent Memory Allocator Enabling Graph Processing

Paper PDF

IEEE Xplore

About

Authors

Keita Iwabuchi (kiwabuchi at llnl dot gov)
Roger A Pearce (rpearce at llnl dot gov)
Maya B Gokhale (gokhale2 at llnl dot gov).

License

Metall is distributed under the terms of both the MIT license and the Apache License (Version 2.0). Users may choose either license, at their option.

All new contributions must be made under both the MIT and Apache-2.0 licenses.

See LICENSE-MIT, LICENSE-APACHE, NOTICE, and COPYRIGHT for details.

SPDX-License-Identifier: (Apache-2.0 OR MIT)

Release

LLNL-CODE-768617

sg0/metall