HACC I/O
Copyright (c) 2012, UChicago Argonne, LLC. All rights reserved.
Originally authored by Venkatram Vishwanath, Argonne National Laboratory. More details available on the official CORAL Benchmarks website.
Compiling
HACC-IO requires only MPI and can be built from the provided makefile via
make CXX=mpicxx
Running
The general syntax for testhacc_io is
mpirun ./testhacc_io numparticles /path/to/outputfile
numparticles is the length of the arrays that each MPI rank should allocate.
HACC IO currently uses this parameter to size the following arrays:
| variable | type | size |
|---|
xx | float | 4 bytes
yy | float | 4 bytes
zz | float | 4 bytes
vx | float | 4 bytes
vy | float | 4 bytes
vz | float | 4 bytes
phi | float | 4 bytes
pid | int64 | 8 bytes
mask | int16 | 2 bytes
So each rank will write out numparticles * 38 bytes worth of data.