NAME

PAPI_get_virt_cyc, PAPI_get_virt_usec - get virtual time counter values

CONTENTS

Synopsis
Description
Errors
Example
Authors
Bugs
See Also

SYNOPSIS

C Interface

#include <papi.h> 

long_long PAPI_get_virt_cyc(void); 

long_long PAPI_get_virt_usec(void); 

Fortran Interface

#include fpapi.h 

PAPIF_get_virt_usec(C_LONG_LONG time) 

PAPIF_get_virt_cyc(C_LONG_LONG virt_cyc) 

PAPI_get_virt_cyc (3) 

DESCRIPTION

Both of these functions return the total number of virtual units from some arbitrary starting point. Virtual units accrue every time the process is running in user-mode on behalf of the process. Like the real time counters, these are guaranteed to exist on every platform PAPI supports. However on some platforms, the resolution can be as bad as 1/Hz as defined by the operating system.

ERRORS

The functions returns PAPI_ECNFLCT if there is no master event set. This will happen if the library has not been initialized, or for threaded applications, if there has been no thread id function defined by the PAPI_thread_init function.

For threaded applications, if there has not yet been any thread specific master event created for the current thread, and if the allocation of such an event set fails, the call will return PAPI_ENOMEMorPAPI_ESYS.

EXAMPLE


long_long s, e;
        
if (PAPI_library_init(PAPI_VER_CURRENT) != PAPI_VER_CURRENT)
  exit(1);

s = PAPI_get_virt_cyc();

your_slow_code();

e = PAPI_get_virt_cyc(); printf("Process has run for cycles: %lld\n",e-s);

AUTHORS

The PAPI Team. See them at the PAPI Web Site: http://icl.cs.utk.edu/projects/papi

BUGS

These functions have no known bugs.

SEE ALSO

PAPI_library_init (3), PAPI_get_real_usec (3), PAPI_get_real_cyc (3)


PAPI Programmer’s Reference PAPI_get_virt_cyc (3) November, 2003

  Innovative Computing Laboratory
2001 R&D Winner  
Contact PAPI: papi@cs.utk.edu Computer Science Department
  University of Tennessee