1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
|
/*
* Distributed under the OSI-approved Apache License, Version 2.0. See
* accompanying file Copyright.txt for details.
*
* bpFlushWriter.cpp: Example that tests buffer overflow forcing a flush to
* transports when writing a large variable in independent N-to-N mode. This
* will have performance penalties, but it's safer.
*
* Created on: Feb 16, 2017
* Author: William F Godoy godoywf@ornl.gov
*/
#include <ios> //std::ios_base::failure
#include <iostream> //std::cout
#include <mpi.h>
#include <stdexcept> //std::invalid_argument std::exception
#include <vector>
#include <adios2.h>
int main(int argc, char *argv[])
{
int provided;
// MPI_THREAD_MULTIPLE is only required if you enable the SST MPI_DP
MPI_Init_thread(&argc, &argv, MPI_THREAD_MULTIPLE, &provided);
int rank, size;
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
MPI_Comm_size(MPI_COMM_WORLD, &size);
/** Application variable */
std::vector<float> myFloats(1000000); //~ 4 MB
const std::size_t Nx = myFloats.size();
try
{
/** ADIOS class factory of IO class objects */
adios2::ADIOS adios(MPI_COMM_WORLD);
/*** IO class object: settings and factory of Settings: Variables,
* Parameters, Transports, and Execution: Engines */
adios2::IO bpIO = adios.DeclareIO("BPFile_N2N_Flush");
bpIO.SetEngine("BPFile");
// bpIO.SetParameters({{"MaxBufferSize", "9Mb"},
// {"BufferGrowthFactor", "1.5"},
// {"Threads", "2"}});
// bpIO.AddTransport("File", {{"ProfileUnits", "Microseconds"}});
/** global array : name, { shape (total) }, { start (local) }, { count
* (local) }, all are constant dimensions */
adios2::Variable<float> bpFloats = bpIO.DefineVariable<float>(
"bpFloats", {size * Nx}, {rank * Nx}, {Nx}, adios2::ConstantDims);
/** Engine derived class, spawned to start IO operations */
adios2::Engine bpWriter = bpIO.Open("myVectorFlush.bp", adios2::Mode::Write);
bpWriter.BeginStep();
for (unsigned int t = 0; t < 100; ++t)
{
/** values to time step */
myFloats.assign(myFloats.size(), static_cast<float>(t));
/** Write variable for buffering */
bpWriter.Put<float>(bpFloats, myFloats.data());
}
bpWriter.EndStep();
/** Create bp file, engine becomes unreachable after this*/
bpWriter.Close();
}
catch (std::invalid_argument &e)
{
std::cout << "Invalid argument exception, STOPPING PROGRAM from rank " << rank << "\n";
std::cout << e.what() << "\n";
}
catch (std::ios_base::failure &e)
{
std::cout << "IO System base failure exception, STOPPING PROGRAM from rank " << rank
<< "\n";
std::cout << e.what() << "\n";
}
catch (std::exception &e)
{
std::cout << "Exception, STOPPING PROGRAM from rank " << rank << "\n";
std::cout << e.what() << "\n";
}
MPI_Finalize();
return 0;
}
|
