我正在尝试将序列化结构从一个等级发送到另一个等级。结果是
Segmentation fault: 11
我不知道它来自哪里。
我试图通过打印出一些值来定位问题,并且代码总是在 MPI_Send
和 MPI_Recv
之间中断,但由于它是段错误,因此无法确定这是问题的根源。请赐教。
int N = 11;
struct tests{
int number;
double *fx;
};
void locateMemoryTests(struct tests *t){
t->fx = (double*) malloc(N*sizeof(double));
}
void he(struct tests *t, int N){
int NRank, MyRank;
MPI_Comm_rank( MPI_COMM_WORLD, &MyRank );
MPI_Comm_size( MPI_COMM_WORLD, &NRank );
int st = MyRank * int(N/2);
int en = (MyRank+1) * int(N/2) + (N%2)*MyRank;
for (int i=st; i<en; i++){
t->fx[i] = i*i + 5*(i + t->number);
}
const int nitems = 2;
int blocklengths[2] = {1, N};
MPI_Datatype types[2] = {MPI_INT, MPI_DOUBLE};
MPI_Datatype mpi_tests_type;
MPI_Aint offsets[2];
offsets[0] = offsetof(tests, number);
offsets[1] = offsetof(tests, fx);
MPI_Type_create_struct(nitems, blocklengths, offsets, types, &mpi_tests_type);
MPI_Type_commit(&mpi_tests_type);
MPI_Comm_rank(MPI_COMM_WORLD, &MyRank);
if (MyRank == 0){
struct tests send;
send.number = t->number;
locateMemoryTests(&send);
for (int i=0; i<N; i++){
send.fx[i] = t->fx[i];
}
MPI_Send(&send, 2, mpi_tests_type, 1, 111, MPI_COMM_WORLD);
}
else if (MyRank == 1){
MPI_Status status;
struct tests recv;
locateMemoryTests(&recv);
MPI_Recv(&recv, 2, mpi_tests_type, 0, 111, MPI_COMM_WORLD, &status);
MPI_Type_free(&mpi_tests_type);
}
int main( int argc, char *argv[] ){
int NRank, MyRank;
MPI_Init( &argc, &argv );
MPI_Comm_rank( MPI_COMM_WORLD, &MyRank );
MPI_Comm_size( MPI_COMM_WORLD, &NRank );
struct tests tt;
tt.number = 5;
locateMemoryTests(&tt);
he(&tt,N);
MPI_Finalize();
return 0;
}
最佳答案
您的 MPI 派生数据类型描述了以下 C struct
struct tests{
int number;
double fx[N];
};
但是你用的是不同的
struct tests{
int number;
double *fx;
};
如果 N
不是常量,您可以声明
struct tests{
int number;
double fx[];
};
正确分配这样的结构
取决于您。
另一种选择是保持相同的struct
定义,并手动MPI_Pack()
和MPI_Unpack()
将数据传入/传出临时缓冲区。
关于c++ - 段错误 : Struct Serialisation and MPI Data Transfer in C++,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/56507811/