Quicksilver is a proxy application that represents some elements of the Mercury workload by solving a simplified dynamic monte carlo particle transport problem. Quicksilver attempts to replicate the memory access patterns, communication patterns, and the branching or divergence of Mercury for problems using multigroup cross sections. OpenMP and MPI are used for parallelization. A GPU version is available. Unified memory is assumed.

Performance of Quicksilver is likely to be dominated by latency bound table look-ups, a highly branchy/divergent code path, and poor vectorization potential.

For more information, visit the LLNL co-design pages.

Instructions to build Quicksilver can be found in the Makefile. Quicksilver is a relatively easy to build code with no external dependencies (except MPI and OpenMP). You should be able to build Quicksilver on nearly any system by customizing the values of only four variables in the Makefile:

• CXX The name of the C++ compiler (with path if necessary) Quicksilver uses C++11 features, so a C++11 compliant compiler should be used.

• CXXFLAGS Command line switches to pass to the C++ compiler when compiling objects and when linking the executable.

• CPPFLAGS Command line switches to pass to the compiler only when compiling objects

• LDFLAGS Command line switches to pass to the compiler only when linking the executable

Sample definitions for a number of common systems are provided.

Quicksilver recognizes a number of pre-processor macros that enable or disable various code features such as MPI, OpenMP, etc. These are described in the Makefile.

For performance measurement run the input file located in Examples/CORAL2_Benchmark/Problem1/Coral2_P1_1.inp

To build sycl version

cd SYCL/build

CXX=icpx cmake ../ -DGPU_AOT=PVC

make -sj

To build sycl version on nvidia backend

source /path/to/clang/

cd SYCL/build

//For A100 Machine

CC=clang CXX=clang++ cmake ../ -DUSE_NVIDIA_BACKEND=YES -DUSE_SM=80

//For H100 Machine

CC=clang CXX=clang++ cmake ../ -DUSE_NVIDIA_BACKEND=YES -DUSE_SM=90

make -sj

To build sycl version on amd backend

source /path/to/clang/

mkdir build && cd build

//For MI-100 Machine

CC=clang CXX=clang++ cmake ../ -DUSE_AMDHIP_BACKEND=gfx908

//For MI-250 Machine

CC=clang CXX=clang++ cmake ../ -DUSE_AMDHIP_BACKEND=gfx90a

make -sj

To build cuda version

cd CUDA/src

make USE_SM=90 CUDA_PATH=/opt/hpc_software/compilers/nvidia/cuda-12.0 -sj //for H100

make USE_SM=80 CUDA_PATH=/opt/hpc_software/compilers/nvidia/cuda-12.0 -sj //for A100

To build hip version

cd HIP/src

make -sj

Quicksilver’s behavior is controlled by a combination of command line options and an input file. All of the parameters that can be set on the command line can also be set in the input file. The input file values will override the command line. Run $ qs –h to see documentation on the available command line switches. Documentation of the input file parameters is in preparation.

Quicksilver also has the property that the output of every run is a valid input file. Hence you can repeat any run for which you have the output file by using that output as an input file.

For benchmarking run the example "Examples/CORAL2_Benchmark/Problem1/Coral2_P1_1.inp"

To run sycl version

export QS_DEVICE=GPU (This flag is required only for SYCL version)

./qs -i ../../Examples/AllScattering/scatteringOnly.inp

To run sycl version on nvidia backend

./qs -i ../../Examples/AllScattering/scatteringOnly.inp

To run sycl version on amd backend

ONEAPI_DEVICE_SELECTOR=hip:* ./qs -i ../../Examples/AllScattering/scatteringOnly.inp

To run cuda version

./qs -i ../../Examples/AllScattering/scatteringOnly.inp

To run hip version

./qs -i ../../Examples/AllScattering/scatteringOnly.inp

Quicksilver is available on github