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Comment:Add another timer on pcache1TruncateUnsafe().
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SHA1: 42ce53f648a506d0a5d9c1231eb28c11b4e6b124
User & Date: drh 2016-08-09 11:44:06
Context
2016-08-10
02:54
Remove all timers and other debugging logs except for the one timer on pcache1TruncateUnsafe(). check-in: 5980e625 user: drh tags: debug
2016-08-09
11:44
Add another timer on pcache1TruncateUnsafe(). check-in: 42ce53f6 user: drh tags: debug
11:23
Add a debug timer to pcache1Truncate(). Change the formatting of some other messages to make them easier to read. check-in: 7d0af4b5 user: dan tags: debug
Changes
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Changes to src/pcache1.c.

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*/
static void pcache1TruncateUnsafe(
  PCache1 *pCache,             /* The cache to truncate */
  unsigned int iLimit          /* Drop pages with this pgno or larger */
){
  TESTONLY( unsigned int nPage = 0; )  /* To assert pCache->nPage is correct */
  unsigned int h;


  assert( sqlite3_mutex_held(pCache->pGroup->mutex) );
  for(h=0; h<pCache->nHash; h++){
    PgHdr1 **pp = &pCache->apHash[h]; 
    PgHdr1 *pPage;
    while( (pPage = *pp)!=0 ){
      if( pPage->iKey>=iLimit ){
        pCache->nPage--;

        *pp = pPage->pNext;
        if( !pPage->isPinned ) pcache1PinPage(pPage);
        pcache1FreePage(pPage);
      }else{
        pp = &pPage->pNext;
        TESTONLY( nPage++; )
      }
    }
  }
  assert( pCache->nPage==nPage );




}

/******************************************************************************/
/******** sqlite3_pcache Methods **********************************************/

/*
** Implementation of the sqlite3_pcache.xInit method.







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*/
static void pcache1TruncateUnsafe(
  PCache1 *pCache,             /* The cache to truncate */
  unsigned int iLimit          /* Drop pages with this pgno or larger */
){
  TESTONLY( unsigned int nPage = 0; )  /* To assert pCache->nPage is correct */
  unsigned int h;
  START_DEBUG_TIMER;
  int nFree = 0;
  assert( sqlite3_mutex_held(pCache->pGroup->mutex) );
  for(h=0; h<pCache->nHash; h++){
    PgHdr1 **pp = &pCache->apHash[h]; 
    PgHdr1 *pPage;
    while( (pPage = *pp)!=0 ){
      if( pPage->iKey>=iLimit ){
        pCache->nPage--;
        nFree++;
        *pp = pPage->pNext;
        if( !pPage->isPinned ) pcache1PinPage(pPage);
        pcache1FreePage(pPage);
      }else{
        pp = &pPage->pNext;
        TESTONLY( nPage++; )
      }
    }
  }
  assert( pCache->nPage==nPage );
  END_DEBUG_TIMER( DEBUG_TIMER_BIG_TIMEOUT ){
    sqlite3_log(SQLITE_NOTICE, "slow pcache1TruncateUnsafe() %lld nFree=%d",
                iDebugTimer, nFree);
  }
}

/******************************************************************************/
/******** sqlite3_pcache Methods **********************************************/

/*
** Implementation of the sqlite3_pcache.xInit method.

Changes to src/sqliteInt.h.

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#define END_DEBUG_TIMER(nDebugUsec) \
  gettimeofday(&debug_timer_var, 0);                                \
  iDebugTimer = 1000000*(sqlite3_uint64)debug_timer_var.tv_sec      \
                +debug_timer_var.tv_usec-iDebugTimerStart;          \
  if( iDebugTimer>=nDebugUsec )



#define DEBUG_TIMER_BIG_TIMEOUT  10000


#define DEBUG_TIMER_SMALL_TIMEOUT 1000


#endif /* _SQLITEINT_H_ */







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#define END_DEBUG_TIMER(nDebugUsec) \
  gettimeofday(&debug_timer_var, 0);                                \
  iDebugTimer = 1000000*(sqlite3_uint64)debug_timer_var.tv_sec      \
                +debug_timer_var.tv_usec-iDebugTimerStart;          \
  if( iDebugTimer>=nDebugUsec )


#ifndef DEBUG_TIMER_BIG_TIMEOUT
# define DEBUG_TIMER_BIG_TIMEOUT  10000
#endif
#ifndef DEBUG_TIMER_SMALL_TIMEOUT
# define DEBUG_TIMER_SMALL_TIMEOUT 1000
#endif

#endif /* _SQLITEINT_H_ */