Gilles Gouaillardet writes:
> clock_gettime() has a higher precision than gettimeofday(), though it
> likely has
> a lower precision and higher overhead than opal_sys_timer_get_cycles()
Do you mean OMPI actually uses cycles for timing somewhere? The
precision of that would be irrelevant, when i
Hello,
Here is a simple `C` program reading a file in parallel with `MPI IO`:
#include
#include
#include "mpi.h"
#define N 10
main( int argc, char **argv )
{
int rank, size;
MPI_Init(&argc, &argv);
MPI_Comm_rank( MPI_COMM_WORLD, &rank );
What version of Open MPI did you execute your test with?
Edgar
On 4/7/2016 1:54 PM, david.froger...@mailoo.org wrote:
Hello,
Here is a simple `C` program reading a file in parallel with `MPI IO`:
#include
#include
#include "mpi.h"
#define N 10
main( int argc,
What version of Open MPI did you execute your test with?
mpirun (Open MPI) 1.8.6
On Thu, Apr 7, 2016 at 9:28 AM, Dave Love wrote:
> ...
> Anyhow, the lesson seems to be that you shouldn't use mpi_wtime if you
> need decent precision or realistic mpi_wtick across implementations.
>
> I certainly hope that this isn't the lesson anyone learns from this. It
is extremely importan
You're right, thanks a lot Edgar!
Quoting Edgar Gabriel (2016-04-07 23:18:46)
> I found the bug in your code. The displacement of the file view has to
> be given in absolute bytes, not in multiples of etypes.
> ---snip---
> The disp displacement argument specifies the position (absolute offset
