NAME

MPI_Wtime - Get the current time in seconds with microsecond precision

SYNOPSIS

#include <mpi.h> 
double MPI_Wtime(void); 
#include <pmpi.h> 
double PMPI_Wtime(void); 

RETURN VALUE

The current time in seconds from an arbitrary point in the past.

DESCRIPTION

The MPI_Wtime() function is used to obtain the current time in microseconds. This function is also implemented as a macro in this MPI implementation. It calls the clock_gettime() function with the clock CLOCK_MONOTONIC_RAW and calculates tv_sec + tv_nsec * 1.0e-9.

PMPI_Wtime() is the profiling version of this function. Note that since this function is usually used as a macro, hooking this function in a profiler will probably not work.

ERRORS

All MPI routines except for MPI_Wtime and MPI_Wtick return an error value. The the current MPI error handler is invoked if this return value is not MPI_SUCCESS. The default error handler aborts, but this may be changed with by using the MPI_Errhandler_set() function. The predefined error handler MPI_ERRORS_RETURN may be used to cause error values to be returned instead. Note that MPI does not guarentee that an MPI program can continue past an error. In this implementation, all errors except MPI_ERR_INTERN or MPI_ERR_OTHER should always be recoverable.

SEE ALSO

MPI_Wtick (3) clock_getttime(2)

• Lockless
• MPI Documentation
• MPI_Wtime