mpi error from ncmpi_end_indep_data

[Wei-keng Liao]

Hi, Jim

After I move the call to ncmpi_wait() to after ncmpi_end_indep_data()
I can reproduce the error.

The problem has been fixed in the latest revision of PnetCDF.


Wei-keng

On Dec 30, 2014, at 12:13 PM, Wei-keng Liao wrote:

> Hi, Jim
> 
> I was not able to reproduce the error. Could you try the following program?
> Also, could you add an error checking for the ncmpi APIs before ncmpi_end_indep_data.
> I wonder if there is an error returned from one of those APIs.
> 
> #include <stdio.h>
> #include <stdlib.h>
> #include <mpi.h>
> #include <pnetcdf.h>
> 
> #define NY 4
> #define NX 10
> #define NDIMS 2
> 
> #define ERR \
>    if (err != NC_NOERR) { \
>        printf("Error at line=%d: %s\n", __LINE__, ncmpi_strerror(err)); \
>    }
> 
> int main(int argc, char** argv)
> {
>    int rank, nprocs, err;
>    int ncid, varid, dimid[2], req, st;
>    MPI_Offset start[2], count[2], stride[2];
>    unsigned char buffer[NY][NX];
> 
>    MPI_Init(&argc, &argv);
>    MPI_Comm_rank(MPI_COMM_WORLD, &rank);
>    MPI_Comm_size(MPI_COMM_WORLD, &nprocs);
> 
>    err = ncmpi_create(MPI_COMM_WORLD, "testfile.nc", NC_CLOBBER|NC_64BIT_DATA,
>                       MPI_INFO_NULL, &ncid);
>    ERR
> 
>    err = ncmpi_def_dim(ncid, "Y", NY,        &dimid[0]); ERR
>    err = ncmpi_def_dim(ncid, "X", NX*nprocs, &dimid[1]); ERR
>    err = ncmpi_def_var(ncid, "var", NC_UBYTE, NDIMS, dimid, &varid); ERR
>    err = ncmpi_enddef(ncid); ERR
> 
>     start[0] = 0;     start[1] = NX*rank;
>     count[0] = NY/2;  count[1] = NX/2;
>    stride[0] = 2;    stride[1] = 2;
>    err = ncmpi_buffer_attach(ncid, NY*NX); ERR
> 
>    err = ncmpi_begin_indep_data(ncid); ERR
>    err = ncmpi_bput_vars_uchar(ncid, varid, start, count, stride,
>                                &buffer[0][0], &req);
>    ERR
>    err = ncmpi_wait(ncid, 1, &req, &st); ERR
>    err = ncmpi_end_indep_data(ncid); ERR
> 
>    err = ncmpi_buffer_detach(ncid); ERR
>    err = ncmpi_close(ncid); ERR
> 
>    MPI_Finalize();
>    return 0;
> }
> 
> 
> Wei-keng
> 
> On Dec 30, 2014, at 10:31 AM, Jim Edwards wrote:
> 
>> Hi Wei-keng,
>> 
>> I have a code block that looks like:
>> 
>>      ncmpi_begin_indep_data(file->fh);
>> 
>>      usage = 0;
>> 
>>      if(ios->io_rank==file->indep_rank){
>> 
>> ierr = ncmpi_bput_vars_uchar(file->fh, varid, start, count, stride, op, &request);;
>> 
>> pio_push_request(file, request);
>> 
>> ierr = ncmpi_inq_buffer_usage(ncid, &usage);
>> 
>> //	printf("%s %d %d\n",__FILE__,__LINE__,usage);
>> 
>>      }
>> 
>> 
>>      ncmpi_end_indep_data(file->fh);
>> 
>> 
>> It's generating an error message on the ncmpi_end_indep_data call:
>> MPI_FILE_WRITE_AT(83): File does not exist
>> 
>> Regardless of the error message the write seems to work fine, any idea what's causing this?
>> 
>> I'm using pnetcdf svn revision 1920 with intel 15 compiler and mpich.
>> 
>> - Jim
>> 
>> 
>> 
>> 
>> 
>> 
>> 
>> 
>> -- 
>> Jim Edwards
>> 
>> CESM Software Engineer
>> National Center for Atmospheric Research
>> Boulder, CO 
>