how to do nonblocking collective i/o

[Liu, Jaln]

Hi,

I want to test the nonblocking i/o of PnetCDF, is there an implementation of non-blocking version's two-phase collective I/O?
Here are the codes I wrote:

else if(isnonblock==1)
      {
        float ** nb_temp_in=malloc(numcalls*sizeof(float *));
        int * request=calloc(numcalls, sizeof(int));
        int * status=calloc(numcalls,sizeof(int));
        int varasize;
        for(j=0;j<numcalls;j++)
        {
          mpi_count[1]=(j>NLVL)?NLVL:j+1;
          varasize=mpi_count[0]*mpi_count[1]*NLAT*NLON;
          nb_temp_in[j]=calloc(varasize,sizeof(float));
          if (ret = ncmpi_iget_vara(ncid, temp_varid, mpi_start,mpi_count,nb_temp_in[j],varasize,MPI_FLOAT,&(request[j])));
          if (ret != NC_NOERR) handle_error(ret);
        }

        ret = ncmpi_wait_all(ncid, numcalls, request, status);
        for (j=0; j<numcalls; j++)
         if (status[j] != NC_NOERR) handle_error(status[j]);
      }

I have two questions,
1, in the above code, what is right way to parallelize the program? by decomposing the for loop " for(j=0;j<numcalls;j++)"?
2, how to do non-blocking collective I/O? is there a function like 'ncmpi_iget_vara_all'?
Thanks for your attention.

Regrads,
Jialin Liu