Are you running from a PVFS directory?
If so, please run command "mount" and "pwd" to confirm that.
I usually us the full file path name in MPI_File_open()
Wei-keng
On Jul 9, 2013, at 5:10 AM, Yves Revaz wrote:
>
> Dear Wei-keng,
>
> Thanks for the corrections. I improved the code and run it again,
> and I get the following output:
>
>
> PE00: write at offset = 0
> PE00: write at offset = 10
> PE00: write at offset = 20
> PE00: write at offset = 30
> PE00: write count = 0
> PE00: write count = 0
> PE00: write count = 0
> PE00: write count = 0
>
> and in addition, the outputfile is still not created !
> So I really suspect an issue with the parallel file system.
>
> yves
>
>
>
> On 07/08/2013 06:15 PM, Wei-keng Liao wrote:
>>> MPI_Exscan(&b,&offset, 1, MPI_INT, MPI_SUM,MPI_COMM_WORLD);
>> Your offset is of type MPI_Offset, an 8-byte integer.
>> Variable b is of type int, a 4-byte integer.
>>
>> Please try change the data type for b to MPI_Offset and use
>> MPI_Exscan(&b,&offset, 1, MPI_OFFSET, MPI_SUM,MPI_COMM_WORLD);
>>
>>
>> Wei-keng
>>
>> On Jul 8, 2013, at 10:58 AM, Yves Revaz wrote:
>>
>>> Dear List,
>>>
>>> I'm facing a problem with the mpi-io on pvfs.
>>> I'm using orangefs-2.8.7 on 6 server nodes.
>>>
>>> I recently tried to play with mpi-io as pvfs is designed to
>>> support parallel access to a single file.
>>>
>>> I used the following simple code (see below) where different processes open
>>> a file
>>> and write each at a different position in the file.
>>>
>>> I compiled it with mpich2, as pvfs seems to only support this version to
>>> use the
>>> parallel access facilities, right ?
>>>
>>> When running my test code on a classical file system, the code works
>>> perfectly and I get the following output:
>>>
>>> mpirun -n 4 ./a.out
>>> PE03: write at offset = 30
>>> PE03: write count = 10
>>> PE00: write at offset = 0
>>> PE00: write count = 10
>>> PE01: write at offset = 10
>>> PE01: write count = 10
>>> PE02: write at offset = 20
>>> PE02: write count = 10
>>>
>>> as expected a file "testfile" is created.
>>> However, the same code acessing my pvfs file system gives:
>>>
>>> mpirun -n 4 ./a.out
>>> PE00: write at offset = 0
>>> PE00: write count = -68457862
>>> PE02: write at offset = 20
>>> PE02: write count = 32951150
>>> PE01: write at offset = 10
>>> PE01: write count = -110085322
>>> PE03: write at offset = 30
>>> PE03: write count = -268114218
>>>
>>> and no file "testfile" is created.
>>>
>>> I'm I doing something wrong ? Do I need to compile orangefs or mpich2 with
>>> particular options ?
>>>
>>> Thanks for your precious help,
>>>
>>> yves
>>>
>>>
>>>
>>> My simple code:
>>> ---------------------
>>>
>>> #include "mpi.h"
>>> #include<stdio.h>
>>> #define BUFSIZE 10
>>>
>>> int main(int argc, char *argv[])
>>> {
>>> int i, me, buf[BUFSIZE];
>>> int b, offset, count;
>>> MPI_File myfile;
>>> MPI_Offset disp;
>>> MPI_Status stat;
>>>
>>> MPI_Init(&argc,&argv);
>>> MPI_Comm_rank(MPI_COMM_WORLD,&me);
>>> for (i=0; i<BUFSIZE; i++)
>>> buf[i] = me*BUFSIZE + i;
>>>
>>> MPI_File_open(MPI_COMM_WORLD, "testfile", MPI_MODE_WRONLY |
>>> MPI_MODE_CREATE,
>>> MPI_INFO_NULL,&myfile);
>>>
>>> offset = 0;
>>> b = BUFSIZE;
>>> MPI_Exscan(&b,&offset, 1, MPI_INT, MPI_SUM,MPI_COMM_WORLD);
>>> disp = offset*sizeof(int);
>>> printf("PE%2.2i: write at offset = %d\n", me, offset);
>>>
>>> MPI_File_set_view(myfile, disp,
>>> MPI_INT, MPI_INT, "native", MPI_INFO_NULL);
>>> MPI_File_write(myfile, buf, BUFSIZE, MPI_INT,
>>> &stat);
>>> MPI_Get_count(&stat, MPI_INT,&count);
>>> printf("PE%2.2i: write count = %d\n", me, count);
>>> MPI_File_close(&myfile);
>>>
>>> MPI_Finalize();
>>>
>>> return 0;
>>> }
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>> --
>>>
>>> ---------------------------------------------------------------------
>>> Dr. Yves Revaz
>>> Laboratory of Astrophysics
>>> Ecole Polytechnique Fédérale de Lausanne (EPFL)
>>> Observatoire de Sauverny Tel : +41 22 379 24 28
>>> 51. Ch. des Maillettes Fax : +41 22 379 22 05
>>> 1290 Sauverny e-mail :
>>> [email protected]
>>>
>>> SWITZERLAND Web :
>>> http://people.epfl.ch/yves.revaz
>>>
>>> ---------------------------------------------------------------------
>>>
>>> _______________________________________________
>>> Pvfs2-users mailing list
>>> [email protected]
>>> http://www.beowulf-underground.org/mailman/listinfo/pvfs2-users
>
>
> --
>
> ---------------------------------------------------------------------
> Dr. Yves Revaz
> Laboratory of Astrophysics
> Ecole Polytechnique Fédérale de Lausanne (EPFL)
> Observatoire de Sauverny Tel : +41 22 379 24 28
> 51. Ch. des Maillettes Fax : +41 22 379 22 05
> 1290 Sauverny e-mail : [email protected]
> SWITZERLAND Web : http://people.epfl.ch/yves.revaz
> ---------------------------------------------------------------------
>
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