1 // Copyright (C) 2005, 2006 Douglas Gregor.
2
3 // Use, modification and distribution is subject to the Boost Software
4 // License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
5 // http://www.boost.org/LICENSE_1_0.txt)
6
7 // A test of the scatter() and scatterv() collectives.
8 #include <iterator>
9 #include <boost/mpi/collectives/scatter.hpp>
10 #include <boost/mpi/collectives/scatterv.hpp>
11 #include <boost/mpi/communicator.hpp>
12 #include <boost/mpi/environment.hpp>
13 #include "gps_position.hpp"
14 #include <boost/serialization/string.hpp>
15 #include <boost/serialization/list.hpp>
16 #include <boost/iterator/counting_iterator.hpp>
17 #include <boost/lexical_cast.hpp>
18
19 #define BOOST_TEST_MODULE mpi_scatter
20 #include <boost/test/included/unit_test.hpp>
21
22 using namespace boost::mpi;
23
24 template<typename Generator>
25 void
scatter_test(const communicator & comm,Generator generator,const char * kind,int root=-1)26 scatter_test(const communicator& comm, Generator generator,
27 const char* kind, int root = -1)
28 {
29 typedef typename Generator::result_type value_type;
30
31 if (root == -1) {
32 for (root = 0; root < comm.size(); ++root)
33 scatter_test(comm, generator, kind, root);
34 } else {
35 using boost::mpi::scatter;
36
37 value_type value;
38
39 if (comm.rank() == root) {
40 std::vector<value_type> values;
41
42 for (int p = 0; p < comm.size(); ++p)
43 values.push_back(generator(p));
44
45 std::cout << "Scattering " << kind << " from root "
46 << root << "..." << std::endl;
47
48 scatter(comm, values, value, root);
49 } else {
50 scatter(comm, value, root);
51 }
52
53 BOOST_CHECK(value == generator(comm.rank()));
54 }
55
56 comm.barrier();
57 }
58
59
60 //
61 // Generators to test with scatter/scatterv
62 //
63 struct int_generator
64 {
65 typedef int result_type;
66
operator ()int_generator67 int operator()(int p) const { return 17 + p; }
68 };
69
70 struct gps_generator
71 {
72 typedef gps_position result_type;
73
operator ()gps_generator74 gps_position operator()(int p) const
75 {
76 return gps_position(39 + p, 16, 20.2799);
77 }
78 };
79
80 struct string_generator
81 {
82 typedef std::string result_type;
83
operator ()string_generator84 std::string operator()(int p) const
85 {
86 std::string result = boost::lexical_cast<std::string>(p);
87 result += " rosebud";
88 if (p != 1) result += 's';
89 return result;
90 }
91 };
92
93 struct string_list_generator
94 {
95 typedef std::list<std::string> result_type;
96
operator ()string_list_generator97 std::list<std::string> operator()(int p) const
98 {
99 std::list<std::string> result;
100 for (int i = 0; i <= p; ++i) {
101 std::string value = boost::lexical_cast<std::string>(i);
102 result.push_back(value);
103 }
104 return result;
105 }
106 };
107
108 std::ostream&
operator <<(std::ostream & out,std::list<std::string> const & l)109 operator<<(std::ostream& out, std::list<std::string> const& l) {
110 out << '[';
111 std::copy(l.begin(), l.end(), std::ostream_iterator<std::string>(out, " "));
112 out << ']';
113 return out;
114 }
115
116 template<typename Generator>
117 void
scatterv_test(const communicator & comm,Generator generator,const char * kind,int root=-1)118 scatterv_test(const communicator& comm, Generator generator,
119 const char* kind, int root = -1)
120 {
121 typedef typename Generator::result_type value_type;
122
123 if (root == -1) {
124 for (root = 0; root < comm.size(); ++root)
125 scatterv_test(comm, generator, kind, root);
126 } else {
127 using boost::mpi::scatterv;
128
129 int mysize = comm.rank() + 1;
130 std::vector<value_type> myvalues(mysize);
131
132 if (comm.rank() == root) {
133 std::vector<value_type> values;
134 std::vector<int> sizes(comm.size());
135
136 // process p will receive p+1 identical generator(p) elements
137 for (int p = 0; p < comm.size(); ++p) {
138 for (int i = 0; i < p+1; ++i)
139 values.push_back(generator(p));
140 sizes[p] = p + 1;
141 }
142
143 std::cout << "Scatteringv " << kind << " from root "
144 << root << "..." << std::endl;
145 assert(mysize == sizes[comm.rank()]);
146 scatterv(comm, values, sizes, &(myvalues[0]), root);
147 } else {
148 scatterv(comm, &(myvalues[0]), mysize, root);
149 }
150
151 for (int i = 0; i < mysize; ++i)
152 BOOST_CHECK(myvalues[i] == generator(comm.rank()));
153 }
154
155 comm.barrier();
156 }
157
158 template<typename Generator>
159 void
scatterd_test(const communicator & comm,Generator generator,const char * kind,int root=-1)160 scatterd_test(const communicator& comm, Generator generator,
161 const char* kind, int root = -1)
162 {
163 typedef typename Generator::result_type value_type;
164
165 if (root == -1) {
166 for (root = 0; root < comm.size(); ++root)
167 scatterv_test(comm, generator, kind, root);
168 } else {
169 using boost::mpi::scatterv;
170
171 int mysize = comm.rank() + 1;
172 std::vector<value_type> myvalues(mysize);
173
174 if (comm.rank() == root) {
175 std::vector<value_type> values;
176 std::vector<int> sizes(comm.size());
177 std::vector<int> displs(comm.size());
178 value_type noise = generator(comm.size()+1);
179 // process p will receive a payload of p+1 identical generator(p) elements
180 // root will insert pseudo random pading between each payload.
181 int shift = 0; // the current position of next payload in source array
182 for (int p = 0; p < comm.size(); ++p) {
183 int size = p+1;
184 int pad = p % 3;
185 // padding
186 for (int i = 0; i < pad; ++i) {
187 values.push_back(noise);
188 }
189 // payload
190 for (int i = 0; i < size; ++i)
191 values.push_back(generator(p));
192 shift += pad;
193 displs[p] = shift;
194 sizes[p] = size;
195 shift += size;
196 }
197
198 std::cout << "Scatteringv " << kind << " from root "
199 << root << "..." << std::endl;
200 assert(mysize == sizes[comm.rank()]);
201 scatterv(comm, values, sizes, displs, &(myvalues[0]), mysize, root);
202 } else {
203 scatterv(comm, &(myvalues[0]), mysize, root);
204 }
205
206 for (int i = 0; i < mysize; ++i)
207 BOOST_CHECK(myvalues[i] == generator(comm.rank()));
208 }
209
210 comm.barrier();
211 }
212
213
BOOST_AUTO_TEST_CASE(simple_scatter)214 BOOST_AUTO_TEST_CASE(simple_scatter)
215 {
216 environment env;
217 communicator comm;
218
219 scatter_test(comm, int_generator(), "integers");
220 scatter_test(comm, gps_generator(), "GPS positions");
221 scatter_test(comm, string_generator(), "string");
222 scatter_test(comm, string_list_generator(), "list of strings");
223
224 scatterv_test(comm, int_generator(), "integers");
225 scatterv_test(comm, gps_generator(), "GPS positions");
226 scatterv_test(comm, string_generator(), "string");
227 scatterv_test(comm, string_list_generator(), "list of strings");
228
229 scatterd_test(comm, int_generator(), "integers");
230 scatterd_test(comm, gps_generator(), "GPS positions");
231 scatterd_test(comm, string_generator(), "string");
232 scatterd_test(comm, string_list_generator(), "list of strings");
233 }
234