MPI Programming Guide

MP_QUERYINTRDELAY, mpc_queryintrdelay

Purpose

Returns the current interrupt delay time.

Library

libmpi.a

C synopsis

#include <pm_util.h>
int mpc_queryintrdelay();

FORTRAN synopsis

MP_QUERYINTRDELAY(INTEGER RC)

Parameters

In FORTRAN, RC will contain one of the values listed under Return Values.

Description

This parallel utility subroutine returns the current interrupt delay time in microseconds.

Notes

• The default interrupt delay time is 35 microseconds for the SP Switch adapter and 1 microsecond for the SP Switch2 adapter.
• This subroutine is thread safe.

Return values

The current interrupt delay time in microseconds.

Examples

C Example

/*
 * Running this program, after compiling with mpcc,
 * without setting the MP_INTRDELAY environment variable,
 * and without using the "-intrdelay" command-line option,
 * produces the following output:
 *
 *    Current interrupt delay time is 35
 *    About to set interrupt delay time to 100...
 *    Current interrupt delay time is 100
 */
 
#include "pm_util.h"
 
main()
{
 printf("Current interrupt delay time is %d\n", mpc_queryintrdelay());
 
 printf("About to set interrupt delay time to 100...\n");
 mpc_setintrdelay(100);
 
 printf("Current interrupt delay time is %d\n", mpc_queryintrdelay());
}
 

FORTRAN Example

Running this program, after compiling with mpxlf, without setting the MP_INTRDELAY environment variable, and without using the "-intrdelay" command-line option, produces the following output:

      Current interrupt delay time is 35
      About to set interrupt delay time to 100...
      Current interrupt delay time is 100
 
 
 
      PROGRAM INTRDELAY_EXAMPLE
 
      INTEGER DELAY, RC
 
      CALL  MP_QUERYINTRDEALY(DELAY)
      WRITE(6,*)'Current interrupt delay time is', delay
 
      WRITE(6,*)'About to set interrupt delay time to 100...'
      DELAY = 100
      CALL MP_SETINTRDELAY(DELAY, RC)
 
      CALL  MP_QUERYINTRDELAY(DELAY)
      WRITE(6,*)'Current interrupt delay time is', delay
 
      STOP
      END
 

Related information

Subroutines:

• MP_DISABLEINTR, mpc_disableintr
• MP_ENABLEINTR, mpc_enableintr
• MP_QUERYINTR, mpc_queryintr
• MP_SETINTRDELAY, mpc_setintrdelay