Hermes

Hermes is a heterogeneous-aware, multi-tiered, dynamic, and distributed I/O buffering system that aims to significantly accelerate I/O performance. See the official site for more information. For design documents, architecture description, performance data, and individual component design, see the wiki.

Dependencies

• A C++ compiler that supports C++ 17.
• Thallium - RPC library for HPC. Use a version greater than 0.5 for RoCE support.
• GLOG - The Google logging library.
• GLPK - GNU Linear Programming Kit
• yaml-cpp - YAML file parser
• MPI (tested with MPICH 3.3.2 and OpenMPI 4.0.3). Note: The MPI-IO adapter only supports MPICH. If you don't need the MPI-IO adapter you can use OpenMPI, but you must define the CMake variable HERMES_ENABLE_MPIIO_ADAPTER=OFF.
• The Catch2 testing framework (only required if built with -DBUILD_TESTING=ON; tested with 3.0.1)

Building

Spack

Spack is the easiest way to get Hermes and all its dependencies installed.

# Install spack if you don't already have it
SPACK_DIR=~/spack
git clone https://github.com/spack/spack ${SPACK_DIR}
. ${SPACK_DIR}/share/spack/setup-env.sh
spack install hermes

If this doesn't work, the Hermes and Mochi spack recipes might be out of sync with the version of spack you're using. In that case, you can try the most up-to-date repos.

# set location of hermes_file_staging
STAGE_DIR=~/hermes_stage
MOCHI_REPO=${STAGE_DIR}/mochi
HERMES_REPO=${STAGE_DIR}/hermes
git clone https://github.com/mochi-hpc/mochi-spack-packages.git ${MOCHI_REPO}
git clone https://github.com/HDFGroup/hermes ${HERMES_REPO}
spack repo add ${MOCHI_REPO}
spack repo add ${HERMES_REPO}/ci/hermes
spack install hermes

CMake

Hermes makes use of the CMake build system and requires an out of source build.

cd /path/to/hermes
mkdir build
cd build
ccmake ..

Type 'c' to configure until there are no errors, then generate the makefile with 'g'. The default options should suffice for most use cases. In addition, we recommend the following options.

-DCMAKE_INSTALL_PREFIX=/installation/prefix
-DCMAKE_PREFIX_PATH=/path/to/dependencies
-DCMAKE_BUILD_RPATH=/path/to/dependencies/lib
-DCMAKE_INSTALL_RPATH=/path/to/dependencies/lib
-DCMAKE_BUILD_TYPE=Release
-DCMAKE_CXX_COMPILER=`which mpicxx`
-DBUILD_SHARED_LIBS=ON

After the makefile has been generated, you can type make -j 4 or cmake --build . -- -j 4. Add VERBOSE=1 to see detailed compiler output.

Testing and Installation

After successfully building Hermes, it's a good idea to run the test suite via the command ctest .. This should be run from the build directory.

Finally, install the library with make install. You can find a complete example build script here.

Contributing

We follow the Google C++ Style Guide. You can run make lint to ensure that your code conforms to the style. This requires the cpplint Python module (pip install cpplint). Alternatively, you can let the CI build inform you of required style changes.