DASH Example bench.12.for_each
Synopsis:
Benchmark for comparing the performance of different for_each implementations. Each for each implementation calculates the sum of the “passed” elements.
Implementations
In all cases the fastet implementation (which fits the interface) for the given task is used.
- std::for_each l.
std::for_each(lbegin, lend, f) - dash::for_each
dash::for_each(begin, end, f) - dash::stl_for_each
dash::stl_for_each(begin, end, f) - dash::for_each_with_index
dash::for_each_with_index(begin, end, f)
Usage (DART-MPI)
$ DASH_MAX_UNIT_THREADS=<T> mpirun -n <P> ./bin/bench.12.for_eachOptions
| Parameter | Description | Default |
|---|---|---|
| \(\texttt{sb}\) | initial size of one dimension of the square NArray | 1000 |
| \(\texttt{tmax}\) | end benchmark if single round takes longer than # seconds | 20 |
Sample Output
Projekt03 Haswell: 20 units, 1 thread / unit
$ mpirun -n 20 ./bin/bench.12.for_each-- Runtime arguments
-- -sb 1000 initial matrix size
-- -tmax 1000 max time in s per iteration
----------------------------------------------------------------------------------
units, mpi.impl, l. size mb, l. elems.s , impl., time fill.s,time foreach.s,time total.s
20, intelmpi, 0.00, 235849.06k, std::for_each l., 0.00, 0.00, 0.00
20, intelmpi, 0.00, 2053.30k, dash::for_each, 0.00, 0.02, 0.03
20, intelmpi, 0.00, 2133.38k, dash::stl_for_each, 0.00, 0.02, 0.02
20, intelmpi, 0.00, 2085.24k,dash::for_each_with_index, 0.00, 0.02, 0.02
20, intelmpi, 0.00, 223964.17k, std::for_each l., 0.00, 0.00, 0.00
20, intelmpi, 0.00, 2059.94k, dash::for_each, 0.00, 0.10, 0.10
20, intelmpi, 0.00, 2131.26k, dash::stl_for_each, 0.00, 0.09, 0.10
20, intelmpi, 0.00, 2087.18k,dash::for_each_with_index, 0.00, 0.10, 0.10
20, intelmpi, 3.00, 225161.84k, std::for_each l., 0.01, 0.00, 0.02
20, intelmpi, 3.00, 2058.80k, dash::for_each, 0.01, 0.39, 0.40
20, intelmpi, 3.00, 2133.98k, dash::stl_for_each, 0.01, 0.37, 0.39
20, intelmpi, 3.00, 2089.24k,dash::for_each_with_index, 0.01, 0.38, 0.40
20, intelmpi, 12.00, 229835.52k, std::for_each l., 0.05, 0.01, 0.07
20, intelmpi, 12.00, 2059.23k, dash::for_each, 0.05, 1.55, 1.61
20, intelmpi, 12.00, 2134.36k, dash::stl_for_each, 0.06, 1.50, 1.56
20, intelmpi, 12.00, 2089.51k,dash::for_each_with_index, 0.06, 1.53, 1.59
20, intelmpi, 48.00, 219595.46k, std::for_each l., 0.22, 0.06, 0.27
20, intelmpi, 48.00, 2059.85k, dash::for_each, 0.22, 6.21, 6.43
20, intelmpi, 48.00, 2134.21k, dash::stl_for_each, 0.22, 6.00, 6.21
20, intelmpi, 48.00, 2089.49k,dash::for_each_with_index, 0.24, 6.13, 6.37