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Sourcecode: postgresql-8.4 version File versions  Download package

instrument.c
/*-------------------------------------------------------------------------
 *
 * instrument.c
 *     functions for instrumentation of plan execution
 *
 *
 * Copyright (c) 2001-2009, PostgreSQL Global Development Group
 *
 * IDENTIFICATION
 *      $PostgreSQL: pgsql/src/backend/executor/instrument.c,v 1.22 2009/01/01 17:23:41 momjian Exp $
 *
 *-------------------------------------------------------------------------
 */
#include "postgres.h"

#include <unistd.h>

#include "executor/instrument.h"


/* Allocate new instrumentation structure(s) */
Instrumentation *
InstrAlloc(int n)
{
      Instrumentation *instr = palloc0(n * sizeof(Instrumentation));

      /* we don't need to do any initialization except zero 'em */

      return instr;
}

/* Entry to a plan node */
void
InstrStartNode(Instrumentation *instr)
{
      if (INSTR_TIME_IS_ZERO(instr->starttime))
            INSTR_TIME_SET_CURRENT(instr->starttime);
      else
            elog(DEBUG2, "InstrStartNode called twice in a row");
}

/* Exit from a plan node */
void
InstrStopNode(Instrumentation *instr, double nTuples)
{
      instr_time  endtime;

      /* count the returned tuples */
      instr->tuplecount += nTuples;

      if (INSTR_TIME_IS_ZERO(instr->starttime))
      {
            elog(DEBUG2, "InstrStopNode called without start");
            return;
      }

      INSTR_TIME_SET_CURRENT(endtime);
      INSTR_TIME_ACCUM_DIFF(instr->counter, endtime, instr->starttime);

      INSTR_TIME_SET_ZERO(instr->starttime);

      /* Is this the first tuple of this cycle? */
      if (!instr->running)
      {
            instr->running = true;
            instr->firsttuple = INSTR_TIME_GET_DOUBLE(instr->counter);
      }
}

/* Finish a run cycle for a plan node */
void
InstrEndLoop(Instrumentation *instr)
{
      double            totaltime;

      /* Skip if nothing has happened, or already shut down */
      if (!instr->running)
            return;

      if (!INSTR_TIME_IS_ZERO(instr->starttime))
            elog(DEBUG2, "InstrEndLoop called on running node");

      /* Accumulate per-cycle statistics into totals */
      totaltime = INSTR_TIME_GET_DOUBLE(instr->counter);

      instr->startup += instr->firsttuple;
      instr->total += totaltime;
      instr->ntuples += instr->tuplecount;
      instr->nloops += 1;

      /* Reset for next cycle (if any) */
      instr->running = false;
      INSTR_TIME_SET_ZERO(instr->starttime);
      INSTR_TIME_SET_ZERO(instr->counter);
      instr->firsttuple = 0;
      instr->tuplecount = 0;
}

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