Вы ошибаетесь в first MPI_Wait (для ранга 0). Это шаг 7 в приведенном ниже примере кода.
Использование mpirun -np 2 ./whatever:
Похоже, что sReqD это , а не , установленный правильно. Это установлено на шаге 5 ранга 1.
Но, шаг 7 выполняется с рангом 0, который не устанавливает sReqD.
Итак, вам нужно настроить свои операторы if, чтобы они соответствовали правильно для того, какой ранг делает, какой MPI_Wait и т. Д.
Вот ваш код с некоторыми операторами отладки printf:
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <time.h>
#include <mpi.h>
int
main(int argc, char *argv[])
{
/* MPI Specific Variables */
int my_size,
my_rank,
up,
down;
MPI_Request reqU,
reqD,
sreqU,
sreqD;
MPI_Status rUstatus,
rDstatus,
sUstatus,
sDstatus;
/* Physical Dimensions */
double Linner = 5.0; /* mm */
double Rinner = 1.0; /* mm */
double phi_0 = 1000.0;
/*V*/
/* Other Variables */
int grid_size = 100;
int slice;
int x,
y;
double grid_res_y = 0.2;
double grid_res_x = 0.1;
int xboundary,
yboundary;
MPI_Init(&argc, &argv);
MPI_Comm_rank(MPI_COMM_WORLD, &my_rank);
MPI_Comm_size(MPI_COMM_WORLD, &my_size);
/* Determining neighbours */
/* if statemets used to stop highest and lowest rank neighbours arent
outside 0 - my_size-1 range of ranks */
if (my_rank != 0) {
up = my_rank - 1;
}
else {
up = 0;
}
if (my_rank != my_size - 1) {
down = my_rank + 1;
}
else {
down = my_size - 1;
}
printf("my_rank=%d my_size=%d up=%d down=%d\n",my_rank,my_size,up,down);
/* cross-check: presumed my_size is a factor of gridsize else there are
odd sized slices and this is not coded for */
if (grid_size % my_size != 0) {
printf("ERROR - number of procs = %d, this is not a factor of grid_size %d\n", my_size, grid_size);
exit(0);
}
/* Set Up Distributed Data Approach */
slice = grid_size / my_size;
/* y grid index of inner conductor wall */
yboundary = Linner / grid_res_y;
/* x grid and individual array index of inner conductor wall */
xboundary = Rinner / grid_res_x;
if (my_rank == 0) {
printf("Linner=%g grid_res_y=%g yboundary=%d\n",
Linner,grid_res_y,yboundary);
printf("Rinner=%g grid_res_x=%g xboundary=%d\n",
Rinner,grid_res_x,xboundary);
printf("slice=%d grid_size=%d phi=%ld\n",
slice,grid_size,sizeof(double) * (slice + 2) * grid_size);
}
/* extra 2 rows to allow for halo data */
double phi[slice + 2][grid_size];
for (y = 0; y < slice + 2; y++) {
for (x = 0; x < grid_size; x++) {
phi[y][x] = 0.0;
}
}
/* Boundary Containing rank does 2 loops. One over part with inner
conductor and one over part without inner conductor */
if (my_rank == 0) {
for (y = 0; y < slice + 1; y++) {
for (x = xboundary; x < grid_size; x++) {
phi[y][x] = phi_0;
}
}
}
if (my_rank < my_size - 1) {
/* send top most strip up one node to be recieved as bottom halo */
printf("1: my_rank=%d MPI_Isend\n",my_rank);
MPI_Isend(&phi[1][0], grid_size, MPI_DOUBLE, down, 1, MPI_COMM_WORLD,
&sreqU);
/* recv top halo from up one node */
printf("2: my_rank=%d MPI_Irecv\n",my_rank);
MPI_Irecv(&phi[slice + 1][0], grid_size, MPI_DOUBLE, down, 2,
MPI_COMM_WORLD, &reqU);
printf("3: my_rank=%d\n",my_rank);
}
if (my_rank > 0) {
/* recv top halo from down one node */
printf("4: my_rank=%d MPI_Irecv\n",my_rank);
MPI_Irecv(&phi[0][0], grid_size, MPI_DOUBLE, up, 2, MPI_COMM_WORLD,
&reqD);
/* send bottom most strip down one node to be recieved as top halo */
printf("5: my_rank=%d MPI_Isend\n",my_rank);
MPI_Isend(&phi[slice][0], grid_size, MPI_DOUBLE, up, 1, MPI_COMM_WORLD,
&sreqD);
printf("6: my_rank=%d\n",my_rank);
}
if (my_rank < my_size - 1) {
/* Wait for send to down one rank to complete */
printf("7: my_rank=%d\n",my_rank);
MPI_Wait(&sreqD, &sDstatus);
printf("8: my_rank=%d\n",my_rank);
/* Wait for recieve from up one rank to complete */
printf("9: my_rank=%d\n",my_rank);
MPI_Wait(&reqD, &rDstatus);
printf("10: my_rank=%d\n",my_rank);
}
if (my_rank > 0) {
/* Wait for send to up down one rank to complete */
printf("11: my_rank=%d\n",my_rank);
MPI_Wait(&sreqU, &sUstatus);
printf("12: my_rank=%d\n",my_rank);
/* Wait for recieve from down one rank to complete */
printf("12: my_rank=%d\n",my_rank);
MPI_Wait(&reqU, &rUstatus);
printf("13: my_rank=%d\n",my_rank);
}
MPI_Finalize();
return 0;
}
Вот вывод. Обратите внимание, что на шаге 7 печатается (то есть до первое MPI_Wait для ранга 0). Но ранг 0 никогда не достигает шага 8 (printf после этого вызова)
my_rank=0 my_size=2 up=0 down=1
Linner=5 grid_res_y=0.2 yboundary=25
Rinner=1 grid_res_x=0.1 xboundary=10
slice=50 grid_size=100 phi=41600
1: my_rank=0 MPI_Isend
2: my_rank=0 MPI_Irecv
3: my_rank=0
7: my_rank=0
my_rank=1 my_size=2 up=0 down=1
4: my_rank=1 MPI_Irecv
5: my_rank=1 MPI_Isend
6: my_rank=1
11: my_rank=1
[manderly:230404] *** Process received signal ***
[manderly:230403] *** Process received signal ***
[manderly:230403] Signal: Segmentation fault (11)
[manderly:230403] Signal code: Address not mapped (1)
[manderly:230403] Failing at address: 0x58
[manderly:230404] Signal: Segmentation fault (11)
[manderly:230404] Signal code: Address not mapped (1)
[manderly:230404] Failing at address: 0x58
[manderly:230403] [ 0] [manderly:230404] [ 0] /lib64/libpthread.so.0(+0x121c0)/lib64/libpthread.so.0(+0x121c0)[0x7fa5478341c0]
[0x7fa0ebe951c0]
[manderly:230404] [ 1] [manderly:230403] [ 1] /usr/lib64/openmpi/lib/libmpi.so.20(ompi_request_default_wait+0x31)[0x7fa0ec0e9a81]
[manderly:230404] [ 2] /usr/lib64/openmpi/lib/libmpi.so.20(ompi_request_default_wait+0x31)[0x7fa547a88a81]
[manderly:230403] [ 2] /usr/lib64/openmpi/lib/libmpi.so.20(PMPI_Wait+0x60)[0x7fa0ec12c350]
[manderly:230404] [ 3] ./fix2[0x400f93]
[manderly:230404] [ 4] /usr/lib64/openmpi/lib/libmpi.so.20(PMPI_Wait+0x60)[0x7fa547acb350]
[manderly:230403] [ 3] ./fix2[0x400ef7]
/lib64/libc.so.6(__libc_start_main+0xea)[0x7fa0ebaedfea]
[manderly:230404] [ 5] ./fix2[0x40081a[manderly:230403] [ 4] ]
[manderly:230404] *** End of error message ***
/lib64/libc.so.6(__libc_start_main+0xea)[0x7fa54748cfea]
[manderly:230403] [ 5] ./fix2[0x40081a]
[manderly:230403] *** End of error message ***
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mpirun noticed that process rank 0 with PID 0 on node manderly exited on signal 11 (Segmentation fault).
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