c++ - MPI_Scatter Segfaulting -


I am working on a parallel sort program to learn MPI, and every time I am having problems with MPI_Scatter I try to run, I get the following: 

  Input reading input inputting input _pidadad (sigclld): [nid 00012] PE exit signal signal segmentation error [NID 00012] 2011- 03-28 10:21:56 APID 23655: Application termination started   
 On the other questions, a basic form really did not answer why I am getting bothered - close to arrays, so I do not want to have problems with non-compatible memory access, and I passed the correct indicators in the right order. I am here. Anyone have any ideas?  
 The source code is below - it is specified for a specific number because I do not want to deal with variable input and rank size yet.  
  #include & lt; Mpi.h & gt; # Include & lt; Iostream & gt; Using the Std :: endl; Using std :: cout; # Include & lt; Fstream & gt; Std :: using ifstream; Using std :: ofstream; # Include & lt; Algorithm & gt; Using the Std :: sort; #define SIZEOF_INPUT 10000000 # defined NUMTHREADS 100 #define SIZEOF_SUBARRAY SIZEOF_INPUT / NUMTHREADS int main (int argc, char ** argv) {MPI_Init (and argc, and argv); Int input [SIZEOF_INPUT]; Int tact [SIZEOF_SUBARRAY]; Int myRank; MPI_Comm_rank (MPI_COMM_WORLD, & myRank); / * Read input from file * / if (myRank == 0) {cout & lt; & Lt; "Input reading" & lt; & Lt; Endl; Ifstream in (argv [1]); For (Int i = 0; I>   
 Any help would be greatly appreciated Regards, Zach   
 
 < P> huh! This took me a while to see it  
 This move is in  MPI_Scatter , sending the sender amount  every  process, not collected in the total Along with; This is the amount to get from each, that is, it matters like  MPI_Scatterv ; The count is for each process, but in this case, it is considered to be the same.  
 Such  
  MPI_Scatter (input, SIZEOF_SUBARRAY, MPI_INT, tempbuf, SIZEOF_SUBARRAY, MPI_INT, 0, MPI_COMM_WORLD); Cout & lt; & Lt; "Rank" & lt; & Lt; My rank & lt; & Lt; "Sorting" & lt; & Lt; Endl; MPI_Gather (tempbuf, SIZEOF_SUBARRAY, MPI_INT, input, SIZEOF_SUBARRAY, MPI_INT, 0, MPI_COMM_WORLD);   
 Works for me.  
 Also, beware of allocating large arrays on the stack; I know that this is just an example problem, but for me it was the cause of accidents. Dynamically do this  
  int * input = new int [SIZEOF_INPUT]; Int * tempbuf = new int [SIZEOF_SUBARRAY]; // .... Delete [] Input; Remove [] tempbuf;   
 Resolved that issue.

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