[MPICH2-dev] Caused collective abort:

[Rajeev Thakur]

This should work. There must be something else wrong with the code, probably
memory related.

Rajeev 

> -----Original Message-----
> From: owner-mpich2-dev at mcs.anl.gov 
> [mailto:owner-mpich2-dev at mcs.anl.gov] On Behalf Of Amit H Kumar
> Sent: Tuesday, November 27, 2007 10:56 AM
> To: mpich2-dev at mcs.anl.gov
> Subject: [MPICH2-dev] Caused collective abort: 
> 
> 
> 
> Hi MPICH2,
> 
> I am having synchronization problem. Which is causing 
> collective abort.
> 
> What I am trying to accomplish.
> As shown below, basic idea is to have every process send some data to
> lowered number process in an overlapped fashion. And I can 
> only continue
> with the computation after I have received the required data. 
>   Data can be
> large at times, for simplicity I am only showing a single 
> valued buff in
> the code.
> 
> I am using MPI_Irecv and MPI_Isend  as show below.
> 
> My Question is:
> When using Non-blocking communication,  each sender initiates a "Send
> start" and continues with computation and waits on a 
> Non-Blocking receive
> with MPI_Waitall as show below: Is it okay to have the sender 
> Wait on both
> of its MPI_Isend and MPI_Irecv initiated at different points 
> in the code ?
> 
> I believe I am doing something wrong here,  because 
> everything works okay
> for a smaller problem size.
> 
> Any help or feedback will be of great help.
> 
> Thank you,
> Amit
> 
> 
> /////////////////CODE
> 
> for(i=NUMBER; i>0; i--)
>  {
>   printf("\nDoing Initialization ...\n");
> 
>  if(i==NUMBER){
>       /*  DO COMPUTATION */
>   } else{
> 
> 
>         /*  Receive Data from the higher numberd process-rank , with
> Process rank Zero receivng from Rank=Size-1 */
> 
>         err = MPI_Irecv(&buff,sizeof(double),
> MPI_DOUBLE,((rank+1)%size),0,MPI_COMM_WORLD, &mrequest[1] );
>         MPI_Waitall(2,mrequest,mstatus);
> 
>       /* After Receiving Continue with Computation*/
> 
>   }/*Else  End*/
> 
>   /*Communication Block*/
>   if(i>1){
>       /*  SEND DATA TO lowered number process-rank*/
>         err = MPI_Isend(&buff,sizeof(double),
> MPI_DOUBLE,((rank+(size-1))%size),0, MPI_COMM_WORLD, &mrequest[0]);
>   }/*if(i>1)*/
> 
>  }/*End of Main For loop*/
> 
>