/ Check-in [6f99b54a]
Login

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Additional performance improvements in sqlite3BtreeNext() and sqlite3BtreePrevious().
Downloads: Tarball | ZIP archive | SQL archive
Timelines: family | ancestors | descendants | both | toTypeFuncs
Files: files | file ages | folders
SHA1:6f99b54aedeb91e46d52f65504d02a9cc61c0062
User & Date: drh 2013-08-19 22:22:41
References
2013-08-20
03:13
Performance optimizations in the VDBE and especially to the OP_Next and related opcodes and in the sqlite3BtreeNext() and sqlite3BtreePrevious() routines. This is a cherrypick of [6f99b54aedeb], [d2efea1682a7], and [d78c5d89de4b]. check-in: 7f72fc4f user: drh tags: trunk
Context
2013-08-20
03:13
Performance optimizations in the VDBE and especially to the OP_Next and related opcodes and in the sqlite3BtreeNext() and sqlite3BtreePrevious() routines. This is a cherrypick of [6f99b54aedeb], [d2efea1682a7], and [d78c5d89de4b]. check-in: 7f72fc4f user: drh tags: trunk
2013-08-19
23:18
Performance improvement to SQL function calls in the VDBE. check-in: d2efea16 user: drh tags: toTypeFuncs
22:22
Additional performance improvements in sqlite3BtreeNext() and sqlite3BtreePrevious(). check-in: 6f99b54a user: drh tags: toTypeFuncs
21:15
Add tointeger() and toreal() SQL functions. check-in: af497072 user: mistachkin tags: toTypeFuncs
Changes
Hide Diffs Unified Diffs Ignore Whitespace Patch

Changes to src/btree.c.

720
721
722
723
724
725
726



727
728
729
730
731
732
733
...
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
....
4793
4794
4795
4796
4797
4798
4799

4800
4801
4802
4803
4804
4805
4806
4807
4808
4809
4810


4811
4812
4813
4814
4815
4816

4817
4818
4819
4820
4821
4822
4823
....
4870
4871
4872
4873
4874
4875
4876


4877
4878
4879
4880
4881
4882
4883
4884
4885
4886
4887
4888


4889
4890
4891
4892
4893
4894

4895
4896
4897
4898
4899
4900
4901
  }
  pCur->eState = CURSOR_INVALID;
  rc = btreeMoveto(pCur, pCur->pKey, pCur->nKey, 0, &pCur->skipNext);
  if( rc==SQLITE_OK ){
    sqlite3_free(pCur->pKey);
    pCur->pKey = 0;
    assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_INVALID );



  }
  return rc;
}

#define restoreCursorPosition(p) \
  (p->eState>=CURSOR_REQUIRESEEK ? \
         btreeRestoreCursorPosition(p) : \
................................................................................
  int rc;

  rc = restoreCursorPosition(pCur);
  if( rc ){
    *pHasMoved = 1;
    return rc;
  }
  if( pCur->eState!=CURSOR_VALID || pCur->skipNext!=0 ){
    *pHasMoved = 1;
  }else{
    *pHasMoved = 0;
  }
  return SQLITE_OK;
}

................................................................................
int sqlite3BtreeNext(BtCursor *pCur, int *pRes){
  int rc;
  int idx;
  MemPage *pPage;

  assert( cursorHoldsMutex(pCur) );
  assert( pRes!=0 );

  if( pCur->eState!=CURSOR_VALID ){
    rc = restoreCursorPosition(pCur);
    if( rc!=SQLITE_OK ){
      return rc;
    }
    if( CURSOR_INVALID==pCur->eState ){
      *pRes = 1;
      return SQLITE_OK;
    }
  }
  if( pCur->skipNext ){


    if( pCur->skipNext>0 ){
      pCur->skipNext = 0;
      *pRes = 0;
      return SQLITE_OK;
    }
    pCur->skipNext = 0;

  }

  pPage = pCur->apPage[pCur->iPage];
  idx = ++pCur->aiIdx[pCur->iPage];
  assert( pPage->isInit );

  /* If the database file is corrupt, it is possible for the value of idx 
................................................................................
** this routine was called, then set *pRes=1.
*/
int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){
  int rc;
  MemPage *pPage;

  assert( cursorHoldsMutex(pCur) );


  pCur->atLast = 0;
  if( pCur->eState!=CURSOR_VALID ){
    if( ALWAYS(pCur->eState>=CURSOR_REQUIRESEEK) ){
      rc = btreeRestoreCursorPosition(pCur);
      if( rc!=SQLITE_OK ) return rc;
    }
    if( CURSOR_INVALID==pCur->eState ){
      *pRes = 1;
      return SQLITE_OK;
    }
  }
  if( pCur->skipNext ){


    if( pCur->skipNext<0 ){
      pCur->skipNext = 0;
      *pRes = 0;
      return SQLITE_OK;
    }
    pCur->skipNext = 0;

  }

  pPage = pCur->apPage[pCur->iPage];
  assert( pPage->isInit );
  if( !pPage->leaf ){
    int idx = pCur->aiIdx[pCur->iPage];
    rc = moveToChild(pCur, get4byte(findCell(pPage, idx)));







>
>
>







 







|







 







>









<
|
>
>
|
|
|
|
|
|
>







 







>
>










<
|
>
>
|
|
|
|
|
|
>







720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
...
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
....
4796
4797
4798
4799
4800
4801
4802
4803
4804
4805
4806
4807
4808
4809
4810
4811
4812

4813
4814
4815
4816
4817
4818
4819
4820
4821
4822
4823
4824
4825
4826
4827
4828
4829
....
4876
4877
4878
4879
4880
4881
4882
4883
4884
4885
4886
4887
4888
4889
4890
4891
4892
4893
4894

4895
4896
4897
4898
4899
4900
4901
4902
4903
4904
4905
4906
4907
4908
4909
4910
4911
  }
  pCur->eState = CURSOR_INVALID;
  rc = btreeMoveto(pCur, pCur->pKey, pCur->nKey, 0, &pCur->skipNext);
  if( rc==SQLITE_OK ){
    sqlite3_free(pCur->pKey);
    pCur->pKey = 0;
    assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_INVALID );
    if( pCur->skipNext && pCur->eState==CURSOR_VALID ){
      pCur->eState = CURSOR_SKIPNEXT;
    }
  }
  return rc;
}

#define restoreCursorPosition(p) \
  (p->eState>=CURSOR_REQUIRESEEK ? \
         btreeRestoreCursorPosition(p) : \
................................................................................
  int rc;

  rc = restoreCursorPosition(pCur);
  if( rc ){
    *pHasMoved = 1;
    return rc;
  }
  if( pCur->eState!=CURSOR_VALID || NEVER(pCur->skipNext!=0) ){
    *pHasMoved = 1;
  }else{
    *pHasMoved = 0;
  }
  return SQLITE_OK;
}

................................................................................
int sqlite3BtreeNext(BtCursor *pCur, int *pRes){
  int rc;
  int idx;
  MemPage *pPage;

  assert( cursorHoldsMutex(pCur) );
  assert( pRes!=0 );
  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
  if( pCur->eState!=CURSOR_VALID ){
    rc = restoreCursorPosition(pCur);
    if( rc!=SQLITE_OK ){
      return rc;
    }
    if( CURSOR_INVALID==pCur->eState ){
      *pRes = 1;
      return SQLITE_OK;
    }

    if( pCur->skipNext ){
      assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_SKIPNEXT );
      pCur->eState = CURSOR_VALID;
      if( pCur->skipNext>0 ){
        pCur->skipNext = 0;
        *pRes = 0;
        return SQLITE_OK;
      }
      pCur->skipNext = 0;
    }
  }

  pPage = pCur->apPage[pCur->iPage];
  idx = ++pCur->aiIdx[pCur->iPage];
  assert( pPage->isInit );

  /* If the database file is corrupt, it is possible for the value of idx 
................................................................................
** this routine was called, then set *pRes=1.
*/
int sqlite3BtreePrevious(BtCursor *pCur, int *pRes){
  int rc;
  MemPage *pPage;

  assert( cursorHoldsMutex(pCur) );
  assert( pRes!=0 );
  assert( pCur->skipNext==0 || pCur->eState!=CURSOR_VALID );
  pCur->atLast = 0;
  if( pCur->eState!=CURSOR_VALID ){
    if( ALWAYS(pCur->eState>=CURSOR_REQUIRESEEK) ){
      rc = btreeRestoreCursorPosition(pCur);
      if( rc!=SQLITE_OK ) return rc;
    }
    if( CURSOR_INVALID==pCur->eState ){
      *pRes = 1;
      return SQLITE_OK;
    }

    if( pCur->skipNext ){
      assert( pCur->eState==CURSOR_VALID || pCur->eState==CURSOR_SKIPNEXT );
      pCur->eState = CURSOR_VALID;
      if( pCur->skipNext<0 ){
        pCur->skipNext = 0;
        *pRes = 0;
        return SQLITE_OK;
      }
      pCur->skipNext = 0;
    }
  }

  pPage = pCur->apPage[pCur->iPage];
  assert( pPage->isInit );
  if( !pPage->leaf ){
    int idx = pCur->aiIdx[pCur->iPage];
    rc = moveToChild(pCur, get4byte(findCell(pPage, idx)));

Changes to src/btreeInt.h.

516
517
518
519
520
521
522
523
524
525
526
527
528
529
530








531
532
533
534
535
536
537
...
540
541
542
543
544
545
546

547
548
549
550
551
552
553
554
555
  u16 aiIdx[BTCURSOR_MAX_DEPTH];        /* Current index in apPage[i] */
  MemPage *apPage[BTCURSOR_MAX_DEPTH];  /* Pages from root to current page */
};

/*
** Potential values for BtCursor.eState.
**
** CURSOR_VALID:
**   Cursor points to a valid entry. getPayload() etc. may be called.
**
** CURSOR_INVALID:
**   Cursor does not point to a valid entry. This can happen (for example) 
**   because the table is empty or because BtreeCursorFirst() has not been
**   called.
**








** CURSOR_REQUIRESEEK:
**   The table that this cursor was opened on still exists, but has been 
**   modified since the cursor was last used. The cursor position is saved
**   in variables BtCursor.pKey and BtCursor.nKey. When a cursor is in 
**   this state, restoreCursorPosition() can be called to attempt to
**   seek the cursor to the saved position.
**
................................................................................
**   on a different connection that shares the BtShared cache with this
**   cursor.  The error has left the cache in an inconsistent state.
**   Do nothing else with this cursor.  Any attempt to use the cursor
**   should return the error code stored in BtCursor.skip
*/
#define CURSOR_INVALID           0
#define CURSOR_VALID             1

#define CURSOR_REQUIRESEEK       2
#define CURSOR_FAULT             3

/* 
** The database page the PENDING_BYTE occupies. This page is never used.
*/
# define PENDING_BYTE_PAGE(pBt) PAGER_MJ_PGNO(pBt)

/*







<
<
<





>
>
>
>
>
>
>
>







 







>
|
|







516
517
518
519
520
521
522



523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
...
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
  u16 aiIdx[BTCURSOR_MAX_DEPTH];        /* Current index in apPage[i] */
  MemPage *apPage[BTCURSOR_MAX_DEPTH];  /* Pages from root to current page */
};

/*
** Potential values for BtCursor.eState.
**



** CURSOR_INVALID:
**   Cursor does not point to a valid entry. This can happen (for example) 
**   because the table is empty or because BtreeCursorFirst() has not been
**   called.
**
** CURSOR_VALID:
**   Cursor points to a valid entry. getPayload() etc. may be called.
**
** CURSOR_SKIPNEXT:
**   Cursor is valid except that the Cursor.skipNext field is non-zero
**   indicating that the next sqlite3BtreeNext() or sqlite3BtreePrevious()
**   operation should be a no-op.
**
** CURSOR_REQUIRESEEK:
**   The table that this cursor was opened on still exists, but has been 
**   modified since the cursor was last used. The cursor position is saved
**   in variables BtCursor.pKey and BtCursor.nKey. When a cursor is in 
**   this state, restoreCursorPosition() can be called to attempt to
**   seek the cursor to the saved position.
**
................................................................................
**   on a different connection that shares the BtShared cache with this
**   cursor.  The error has left the cache in an inconsistent state.
**   Do nothing else with this cursor.  Any attempt to use the cursor
**   should return the error code stored in BtCursor.skip
*/
#define CURSOR_INVALID           0
#define CURSOR_VALID             1
#define CURSOR_SKIPNEXT          2
#define CURSOR_REQUIRESEEK       3
#define CURSOR_FAULT             4

/* 
** The database page the PENDING_BYTE occupies. This page is never used.
*/
# define PENDING_BYTE_PAGE(pBt) PAGER_MJ_PGNO(pBt)

/*