C中使用MPI的分段错误?
所以我需要在C中使用MPI并行实现一个向量加法函数。 不幸的是,当我运行它时,它会打印大量内存位置的跟踪,然后显示以下消息:C中使用MPI的分段错误?,c,parallel-processing,mpi,C,Parallel Processing,Mpi,所以我需要在C中使用MPI并行实现一个向量加法函数。 不幸的是,当我运行它时,它会打印大量内存位置的跟踪,然后显示以下消息: ================================================================================== = BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES = PID 2419 RUNNING AT hbaum-pc = EXIT CODE:
==================================================================================
= BAD TERMINATION OF ONE OF YOUR APPLICATION PROCESSES
= PID 2419 RUNNING AT hbaum-pc
= EXIT CODE: 6
= CLEANING UP REMAINING PROCESSES
= YOU CAN IGNORE THE BELOW CLEANUP MESSAGES
===================================================================================
YOUR APPLICATION TERMINATED WITH THE EXIT STRING: Aborted (signal 6)
This typically refers to a problem with your application.
Please see the FAQ page for debugging suggestions
这是我的功能代码:
double* vector_vector_addition_parallel(double* a, double* b, int length)
{
int rank, size, error;
double* result = (double*)malloc(sizeof(double)*length);
error = MPI_Init(NULL,NULL);
error = MPI_Comm_size(MPI_COMM_WORLD,&size);
error = MPI_Comm_rank(MPI_COMM_WORLD,&rank);
int sublist_length = (int)(length/size);
double* sub_a = (double*)malloc(sizeof(double) * sublist_length);
double* sub_b = (double*)malloc(sizeof(double) * sublist_length);
error = MPI_Scatter(a, sublist_length, MPI_DOUBLE, sub_a, sublist_length, MPI_DOUBLE, 0, MPI_COMM_WORLD);
error = MPI_Scatter(b, sublist_length, MPI_DOUBLE, sub_b, sublist_length, MPI_DOUBLE, 0, MPI_COMM_WORLD);
double* buffer = (double*)malloc(sizeof(double)*sublist_length);
for(int i = 0; i < sublist_length; i++)
{
buffer[i] = sub_a[i] + sub_b[i];
}
error = MPI_Gather(buffer,sublist_length,MPI_DOUBLE,result,length,MPI_DOUBLE,0,MPI_COMM_WORLD);
error = MPI_Finalize();
return result;
}
我用
mpicc <source_file>
mpicc
并运行它
mpiexec -n 4 <path_to_executable>
mpiexec-n4
我还尝试使用gdb调试代码,但根据gdb的说法,没有问题,而且非常好。当我使用printf输出向量时,当我通过gdb运行程序时,它甚至会打印正确的向量
我认为我使用MPI_Gather的方式有问题,因为当我注释它时,代码将在没有分段错误的情况下运行,尽管显然不是正确的答案,因为我需要使用MPI_Gather来获得结果
如何改进代码以避免出现分段错误?事实上,您的
MPI\u聚集是一个问题。接收计数参数应该是从任何单个进程接收的元素数。因此,对于记录
,您应该传递子列表的长度
,而不是长度
,即:
MPI_Gather(buffer,sublist_length,MPI_DOUBLE,result,sublist_length,MPI_DOUBLE,0,MPI_COMM_WORLD);
谢谢!很好用!
MPI_Gather(buffer,sublist_length,MPI_DOUBLE,result,sublist_length,MPI_DOUBLE,0,MPI_COMM_WORLD);