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
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
|
/*
* Copyright (C) by Argonne National Laboratory
* See COPYRIGHT in top-level directory
*/
/* This program provides a simple test of send-receive performance between
two (or more) processes. This sometimes called head-to-head or
ping-ping test, as both processes send at the same time.
*/
#include "mpi.h"
#include <stdio.h>
#include <stdlib.h>
#include "mpitest.h"
#define MAXTESTS 32
#define ERROR_MARGIN 1.0 /* FIXME: This number is pretty much randomly chosen */
static int verbose = 0;
int main(int argc, char *argv[])
{
int wsize, wrank, partner, len, maxlen, k, reps, repsleft;
double t1;
MPI_Request rreq;
char *rbuf, *sbuf;
double times[3][MAXTESTS];
MTest_Init(&argc, &argv);
if (getenv("MPITEST_VERBOSE"))
verbose = 1;
MPI_Comm_size(MPI_COMM_WORLD, &wsize);
MPI_Comm_rank(MPI_COMM_WORLD, &wrank);
if (wsize < 2) {
fprintf(stderr, "This program requires at least 2 processes\n");
MPI_Abort(MPI_COMM_WORLD, 1);
}
/* Set partner based on whether rank is odd or even */
if (wrank & 0x1) {
partner = wrank - 1;
} else if (wrank < wsize - 1) {
partner = wrank + 1;
} else
/* Handle wsize odd */
partner = MPI_PROC_NULL;
/* Allocate and initialize buffers */
maxlen = 1024 * 1024;
rbuf = (char *) malloc(maxlen);
sbuf = (char *) malloc(maxlen);
if (!rbuf || !sbuf) {
fprintf(stderr, "Could not allocate %d byte buffers\n", maxlen);
MPI_Abort(MPI_COMM_WORLD, 2);
}
for (k = 0; k < maxlen; k++) {
rbuf[k] = 0;
sbuf[k] = 0;
}
MPI_Barrier(MPI_COMM_WORLD);
/* Test Irecv and send, head to head */
if (wrank == 0 && verbose) {
printf("Irecv-send\n");
printf("len\ttime \trate\n");
}
/* Send powers of 2 bytes */
len = 1;
for (k = 0; k < 20; k++) {
/* We use a simple linear form for the number of tests to
* reduce the impact of the granularity of the timer */
reps = 50 - k;
repsleft = reps;
/* Make sure that both processes are ready to start */
MPI_Sendrecv(MPI_BOTTOM, 0, MPI_BYTE, partner, 0,
MPI_BOTTOM, 0, MPI_BYTE, partner, 0, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
t1 = MPI_Wtime();
while (repsleft--) {
MPI_Irecv(rbuf, len, MPI_BYTE, partner, k, MPI_COMM_WORLD, &rreq);
MPI_Send(sbuf, len, MPI_BYTE, partner, k, MPI_COMM_WORLD);
MPI_Wait(&rreq, MPI_STATUS_IGNORE);
}
t1 = MPI_Wtime() - t1;
times[0][k] = t1 / reps;
if (wrank == 0) {
t1 = t1 / reps;
if (t1 > 0) {
t1 = t1 * 1.e6;
if (verbose)
printf("%d\t%g\t%g\n", len, t1, len / t1);
} else {
t1 = t1 * 1.e6;
if (verbose)
printf("%d\t%g\tINF\n", len, t1);
}
if (verbose)
fflush(stdout);
}
len *= 2;
}
MPI_Barrier(MPI_COMM_WORLD);
/* Test Sendrecv, head to head */
if (wrank == 0 && verbose) {
printf("Sendrecv\n");
printf("len\ttime (usec)\trate (MB/s)\n");
}
/* Send powers of 2 bytes */
len = 1;
for (k = 0; k < 20; k++) {
/* We use a simple linear form for the number of tests to
* reduce the impact of the granularity of the timer */
reps = 50 - k;
repsleft = reps;
/* Make sure that both processes are ready to start */
MPI_Sendrecv(MPI_BOTTOM, 0, MPI_BYTE, partner, 0,
MPI_BOTTOM, 0, MPI_BYTE, partner, 0, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
t1 = MPI_Wtime();
while (repsleft--) {
MPI_Sendrecv(sbuf, len, MPI_BYTE, partner, k,
rbuf, len, MPI_BYTE, partner, k, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
}
t1 = MPI_Wtime() - t1;
times[1][k] = t1 / reps;
if (wrank == 0) {
t1 = t1 / reps;
if (t1 > 0) {
t1 = t1 * 1.e6;
if (verbose)
printf("%d\t%g\t%g\n", len, t1, len / t1);
} else {
t1 = t1 * 1.e6;
if (verbose)
printf("%d\t%g\tINF\n", len, t1);
}
if (verbose)
fflush(stdout);
}
len *= 2;
}
MPI_Barrier(MPI_COMM_WORLD);
/* Test Send/recv, ping-pong */
if (wrank == 0 && verbose) {
printf("Pingpong\n");
printf("len\ttime (usec)\trate (MB/s)\n");
}
/* Send powers of 2 bytes */
len = 1;
for (k = 0; k < 20; k++) {
/* We use a simple linear form for the number of tests to
* reduce the impact of the granularity of the timer */
reps = 50 - k;
repsleft = reps;
/* Make sure that both processes are ready to start */
MPI_Sendrecv(MPI_BOTTOM, 0, MPI_BYTE, partner, 0,
MPI_BOTTOM, 0, MPI_BYTE, partner, 0, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
t1 = MPI_Wtime();
while (repsleft--) {
if (wrank & 0x1) {
MPI_Send(sbuf, len, MPI_BYTE, partner, k, MPI_COMM_WORLD);
MPI_Recv(rbuf, len, MPI_BYTE, partner, k, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
} else {
MPI_Recv(rbuf, len, MPI_BYTE, partner, k, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
MPI_Send(sbuf, len, MPI_BYTE, partner, k, MPI_COMM_WORLD);
}
}
t1 = MPI_Wtime() - t1;
times[2][k] = t1 / reps;
if (wrank == 0) {
t1 = t1 / reps;
if (t1 > 0) {
t1 = t1 * 1.e6;
if (verbose)
printf("%d\t%g\t%g\n", len, t1, len / t1);
} else {
t1 = t1 * 1.e6;
if (verbose)
printf("%d\t%g\tINF\n", len, t1);
}
if (verbose)
fflush(stdout);
}
len *= 2;
}
/* At this point, we could optionally analyze the results and report
* success or failure based on some criteria, such as near monotone
* increases in bandwidth. This test was created because of a
* fall-off in performance noted in the ch3:sock device:channel */
int nPerfErrors = 0;
if (wrank == 0) {
len = 1;
for (k = 0; k < 20; k++) {
double T0, T1, T2;
T0 = times[0][k] * 1.e6;
T1 = times[1][k] * 1.e6;
T2 = times[2][k] * 1.e6;
if (verbose)
printf("%d\t%12.2f\t%12.2f\t%12.2f\n", len, T0, T1, T2);
/* Lets look at long messages only */
if (k > 10) {
double T0Old, T1Old, T2Old;
T0Old = times[0][k - 1] * 1.0e6;
T1Old = times[1][k - 1] * 1.0e6;
T2Old = times[2][k - 1] * 1.0e6;
if (T0 > (2 + ERROR_MARGIN) * T0Old) {
nPerfErrors++;
if (verbose)
printf("Irecv-Send:\t%d\t%12.2f\t%12.2f\n", len, T0Old, T0);
}
if (T1 > (2 + ERROR_MARGIN) * T1Old) {
nPerfErrors++;
if (verbose)
printf("Sendrecv:\t%d\t%12.2f\t%12.2f\n", len, T1Old, T1);
}
if (T2 > (2 + ERROR_MARGIN) * T2Old) {
nPerfErrors++;
if (verbose)
printf("Pingpong:\t%d\t%12.2f\t%12.2f\n", len, T2Old, T2);
}
}
len *= 2;
}
fflush(stdout);
}
free(sbuf);
free(rbuf);
MTest_Finalize(nPerfErrors);
return MTestReturnValue(nPerfErrors);
}
|
