Add the BtCursor.pPage field which is the current page to which the cursor
points, for a very small performance gain.
FossilOrigin-Name: a200e1eae9a1350ed2aed9bfe70042fec05dd98b
diff --git a/manifest b/manifest
index 2bcb4fd..7077460 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Prevent\sthe\sfetchPayload()\sroutine\sfrom\sreporting\sa\scell\ssize\sthat\sextends\noff\sthe\send\sof\sthe\spage\son\sa\spathologically\scorrupted\sdatabase\sfile.
-D 2015-04-15T17:26:55.979
+C Add\sthe\sBtCursor.pPage\sfield\swhich\sis\sthe\scurrent\spage\sto\swhich\sthe\scursor\npoints,\sfor\sa\svery\ssmall\sperformance\sgain.
+D 2015-04-15T19:13:26.759
F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
F Makefile.in 5f78b1ab81b64e7c57a75d170832443e66c0880a
F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -173,9 +173,9 @@
F src/backup.c ff743689c4d6c5cb55ad42ed9d174b2b3e71f1e3
F src/bitvec.c 19a4ba637bd85f8f63fc8c9bae5ade9fb05ec1cb
F src/btmutex.c 45a968cc85afed9b5e6cf55bf1f42f8d18107f79
-F src/btree.c c6e32d84442f79d5b96965265d65b3baa231dffc
+F src/btree.c 485e357f2409b1d23f21e542190764ea707d567f
F src/btree.h 969adc948e89e449220ff0ff724c94bb2a52e9f1
-F src/btreeInt.h 973a22a6fd61350b454ad614832b1f0a5e25a1e4
+F src/btreeInt.h 3c791196f75a737b234aee7ba36b37160373fc18
F src/build.c 01b969b20a44a3d9620e597d9af8242348123540
F src/callback.c 7b44ce59674338ad48b0e84e7b72f935ea4f68b0
F src/complete.c a5cf5b4b56390cfb7b8636e8f7ddef90258dd575
@@ -1250,7 +1250,10 @@
F tool/warnings-clang.sh f6aa929dc20ef1f856af04a730772f59283631d4
F tool/warnings.sh 0abfd78ceb09b7f7c27c688c8e3fe93268a13b32
F tool/win/sqlite.vsix deb315d026cc8400325c5863eef847784a219a2f
-P 61d72e17916bc043ce53c64e5ba7050a9bae554e
-R a75e3890d67000037a79bd4d7c9f248e
+P f71053cf658b3260a32ac06f8ba5c2cde0ea54dd
+R a88b52422fda2f2ea905aaa2e3a17ff4
+T *branch * btree-current-page-cache
+T *sym-btree-current-page-cache *
+T -sym-trunk *
U drh
-Z c0a93418012c7dd834fb5d24bb6e0682
+Z 4cafb2843490ebe751738bc5633d8f3a
diff --git a/manifest.uuid b/manifest.uuid
index ec95ab7..8811cda 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-f71053cf658b3260a32ac06f8ba5c2cde0ea54dd
\ No newline at end of file
+a200e1eae9a1350ed2aed9bfe70042fec05dd98b
\ No newline at end of file
diff --git a/src/btree.c b/src/btree.c
index 51fca4b..046c177 100644
--- a/src/btree.c
+++ b/src/btree.c
@@ -587,6 +587,7 @@
pCur->apPage[i] = 0;
}
pCur->iPage = -1;
+ pCur->pPage = 0;
}
@@ -3651,6 +3652,7 @@
releasePage(p->apPage[i]);
p->apPage[i] = 0;
}
+ p->pPage = 0;
}
sqlite3BtreeLeave(pBtree);
}
@@ -3865,6 +3867,7 @@
** variables and link the cursor into the BtShared list. */
pCur->pgnoRoot = (Pgno)iTable;
pCur->iPage = -1;
+ pCur->pPage = 0;
pCur->pKeyInfo = pKeyInfo;
pCur->pBtree = p;
pCur->pBt = pBt;
@@ -3966,7 +3969,8 @@
CellInfo info;
int iPage = pCur->iPage;
memset(&info, 0, sizeof(info));
- btreeParseCell(pCur->apPage[iPage], pCur->aiIdx[iPage], &info);
+ assert( pCur->pPage==pCur->apPage[iPage] );
+ btreeParseCell(pCur->pPage, pCur->aiIdx[iPage], &info);
assert( CORRUPT_DB || memcmp(&info, &pCur->info, sizeof(info))==0 );
}
#else
@@ -3977,7 +3981,8 @@
static void getCellInfo(BtCursor *pCur){
if( pCur->info.nSize==0 ){
int iPage = pCur->iPage;
- btreeParseCell(pCur->apPage[iPage],pCur->aiIdx[iPage],&pCur->info);
+ assert( pCur->pPage==pCur->apPage[iPage] );
+ btreeParseCell(pCur->pPage,pCur->aiIdx[iPage],&pCur->info);
pCur->curFlags |= BTCF_ValidNKey;
}else{
assertCellInfo(pCur);
@@ -3988,7 +3993,8 @@
#define getCellInfo(pCur) \
if( pCur->info.nSize==0 ){ \
int iPage = pCur->iPage; \
- btreeParseCell(pCur->apPage[iPage],pCur->aiIdx[iPage],&pCur->info); \
+ assert( pCur->pPage==pCur->apPage[iPage] ); \
+ btreeParseCell(pCur->pPage,pCur->aiIdx[iPage],&pCur->info); \
pCur->curFlags |= BTCF_ValidNKey; \
}else{ \
assertCellInfo(pCur); \
@@ -4043,7 +4049,8 @@
assert( pCur->eState==CURSOR_VALID );
assert( pCur->iPage>=0 );
assert( pCur->iPage<BTCURSOR_MAX_DEPTH );
- assert( pCur->apPage[pCur->iPage]->intKeyLeaf==1 );
+ assert( pCur->pPage==pCur->apPage[pCur->iPage] );
+ assert( pCur->pPage->intKeyLeaf==1 );
getCellInfo(pCur);
*pSize = pCur->info.nPayload;
return SQLITE_OK;
@@ -4197,14 +4204,15 @@
unsigned char *aPayload;
int rc = SQLITE_OK;
int iIdx = 0;
- MemPage *pPage = pCur->apPage[pCur->iPage]; /* Btree page of current entry */
- BtShared *pBt = pCur->pBt; /* Btree this cursor belongs to */
+ MemPage *pPage = pCur->pPage; /* Btree page of current entry */
+ BtShared *pBt = pCur->pBt; /* Btree this cursor belongs to */
#ifdef SQLITE_DIRECT_OVERFLOW_READ
unsigned char * const pBufStart = pBuf;
int bEnd; /* True if reading to end of data */
#endif
assert( pPage );
+ assert( pPage==pCur->apPage[pCur->iPage] );
assert( pCur->eState==CURSOR_VALID );
assert( pCur->aiIdx[pCur->iPage]<pPage->nCell );
assert( cursorHoldsMutex(pCur) );
@@ -4394,8 +4402,10 @@
int sqlite3BtreeKey(BtCursor *pCur, u32 offset, u32 amt, void *pBuf){
assert( cursorHoldsMutex(pCur) );
assert( pCur->eState==CURSOR_VALID );
- assert( pCur->iPage>=0 && pCur->apPage[pCur->iPage] );
- assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );
+ assert( pCur->iPage>=0 );
+ assert( pCur->apPage[pCur->iPage]==pCur->pPage );
+ assert( pCur->pPage!=0 );
+ assert( pCur->aiIdx[pCur->iPage]<pCur->pPage->nCell );
return accessPayload(pCur, offset, amt, (unsigned char*)pBuf, 0);
}
@@ -4421,8 +4431,10 @@
rc = restoreCursorPosition(pCur);
if( rc==SQLITE_OK ){
assert( pCur->eState==CURSOR_VALID );
- assert( pCur->iPage>=0 && pCur->apPage[pCur->iPage] );
- assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );
+ assert( pCur->iPage>=0 );
+ assert( pCur->apPage[pCur->iPage]==pCur->pPage );
+ assert( pCur->pPage!=0 );
+ assert( pCur->aiIdx[pCur->iPage]<pCur->pPage->nCell );
rc = accessPayload(pCur, offset, amt, pBuf, 0);
}
return rc;
@@ -4452,15 +4464,18 @@
u32 *pAmt /* Write the number of available bytes here */
){
u32 amt;
- assert( pCur!=0 && pCur->iPage>=0 && pCur->apPage[pCur->iPage]);
+ assert( pCur!=0 );
+ assert( pCur->iPage>=0 );
+ assert( pCur->apPage[pCur->iPage]==pCur->pPage );
+ assert( pCur->pPage!=0 );
assert( pCur->eState==CURSOR_VALID );
assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
assert( cursorHoldsMutex(pCur) );
- assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );
+ assert( pCur->aiIdx[pCur->iPage]<pCur->pPage->nCell );
assert( pCur->info.nSize>0 );
- assert( pCur->info.pPayload>pCur->apPage[pCur->iPage]->aData || CORRUPT_DB );
- assert( pCur->info.pPayload<pCur->apPage[pCur->iPage]->aDataEnd ||CORRUPT_DB);
- amt = (int)(pCur->apPage[pCur->iPage]->aDataEnd - pCur->info.pPayload);
+ assert( pCur->info.pPayload>pCur->pPage->aData || CORRUPT_DB );
+ assert( pCur->info.pPayload<pCur->pPage->aDataEnd || CORRUPT_DB );
+ amt = (int)(pCur->pPage->aDataEnd - pCur->info.pPayload);
if( pCur->info.nLocal<amt ) amt = pCur->info.nLocal;
*pAmt = amt;
return (void*)pCur->info.pPayload;
@@ -4514,7 +4529,7 @@
rc = getAndInitPage(pBt, newPgno, &pNewPage,
(pCur->curFlags & BTCF_WriteFlag)==0 ? PAGER_GET_READONLY : 0);
if( rc ) return rc;
- pCur->apPage[i+1] = pNewPage;
+ pCur->apPage[i+1] = pCur->pPage = pNewPage;
pCur->aiIdx[i+1] = 0;
pCur->iPage++;
@@ -4560,16 +4575,18 @@
assert( cursorHoldsMutex(pCur) );
assert( pCur->eState==CURSOR_VALID );
assert( pCur->iPage>0 );
- assert( pCur->apPage[pCur->iPage] );
+ assert( pCur->pPage==pCur->apPage[pCur->iPage] );
+ assert( pCur->pPage!=0 );
assertParentIndex(
pCur->apPage[pCur->iPage-1],
pCur->aiIdx[pCur->iPage-1],
- pCur->apPage[pCur->iPage]->pgno
+ pCur->pPage->pgno
);
testcase( pCur->aiIdx[pCur->iPage-1] > pCur->apPage[pCur->iPage-1]->nCell );
- releasePage(pCur->apPage[pCur->iPage]);
+ releasePage(pCur->pPage);
pCur->iPage--;
+ pCur->pPage = pCur->apPage[pCur->iPage];
pCur->info.nSize = 0;
pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
}
@@ -4625,7 +4642,8 @@
}
pCur->iPage = 0;
}
- pRoot = pCur->apPage[0];
+ assert( pCur->iPage==0 );
+ pRoot = pCur->pPage = pCur->apPage[0];
assert( pRoot->pgno==pCur->pgnoRoot );
/* If pCur->pKeyInfo is not NULL, then the caller that opened this cursor
@@ -4675,7 +4693,7 @@
assert( cursorHoldsMutex(pCur) );
assert( pCur->eState==CURSOR_VALID );
- while( rc==SQLITE_OK && !(pPage = pCur->apPage[pCur->iPage])->leaf ){
+ while( rc==SQLITE_OK && !(pPage = pCur->pPage)->leaf ){
assert( pCur->aiIdx[pCur->iPage]<pPage->nCell );
pgno = get4byte(findCell(pPage, pCur->aiIdx[pCur->iPage]));
rc = moveToChild(pCur, pgno);
@@ -4700,7 +4718,7 @@
assert( cursorHoldsMutex(pCur) );
assert( pCur->eState==CURSOR_VALID );
- while( !(pPage = pCur->apPage[pCur->iPage])->leaf ){
+ while( !(pPage = pCur->pPage)->leaf ){
pgno = get4byte(&pPage->aData[pPage->hdrOffset+8]);
pCur->aiIdx[pCur->iPage] = pPage->nCell;
rc = moveToChild(pCur, pgno);
@@ -4723,11 +4741,12 @@
assert( sqlite3_mutex_held(pCur->pBtree->db->mutex) );
rc = moveToRoot(pCur);
if( rc==SQLITE_OK ){
+ assert( pCur->pPage==pCur->apPage[pCur->iPage] );
if( pCur->eState==CURSOR_INVALID ){
- assert( pCur->pgnoRoot==0 || pCur->apPage[pCur->iPage]->nCell==0 );
+ assert( pCur->pgnoRoot==0 || pCur->pPage->nCell==0 );
*pRes = 1;
}else{
- assert( pCur->apPage[pCur->iPage]->nCell>0 );
+ assert( pCur->pPage->nCell>0 );
*pRes = 0;
rc = moveToLeftmost(pCur);
}
@@ -4754,8 +4773,9 @@
for(ii=0; ii<pCur->iPage; ii++){
assert( pCur->aiIdx[ii]==pCur->apPage[ii]->nCell );
}
- assert( pCur->aiIdx[pCur->iPage]==pCur->apPage[pCur->iPage]->nCell-1 );
- assert( pCur->apPage[pCur->iPage]->leaf );
+ assert( pCur->pPage==pCur->apPage[pCur->iPage] );
+ assert( pCur->aiIdx[pCur->iPage]==pCur->pPage->nCell-1 );
+ assert( pCur->pPage->leaf );
#endif
return SQLITE_OK;
}
@@ -4853,19 +4873,20 @@
if( rc ){
return rc;
}
- assert( pCur->pgnoRoot==0 || pCur->apPage[pCur->iPage] );
- assert( pCur->pgnoRoot==0 || pCur->apPage[pCur->iPage]->isInit );
- assert( pCur->eState==CURSOR_INVALID || pCur->apPage[pCur->iPage]->nCell>0 );
+ assert( pCur->pgnoRoot==0 || pCur->apPage[pCur->iPage]==pCur->pPage );
+ assert( pCur->pgnoRoot==0 || pCur->pPage!=0 );
+ assert( pCur->pgnoRoot==0 || pCur->pPage->isInit );
+ assert( pCur->eState==CURSOR_INVALID || pCur->pPage->nCell>0 );
if( pCur->eState==CURSOR_INVALID ){
*pRes = -1;
- assert( pCur->pgnoRoot==0 || pCur->apPage[pCur->iPage]->nCell==0 );
+ assert( pCur->pgnoRoot==0 || pCur->pPage->nCell==0 );
return SQLITE_OK;
}
- assert( pCur->apPage[0]->intKey || pIdxKey );
+ assert( pCur->pPage->intKey || pIdxKey );
for(;;){
int lwr, upr, idx, c;
Pgno chldPg;
- MemPage *pPage = pCur->apPage[pCur->iPage];
+ MemPage *pPage = pCur->pPage;
u8 *pCell; /* Pointer to current cell in pPage */
/* pPage->nCell must be greater than zero. If this is the root-page
@@ -4988,7 +5009,7 @@
assert( lwr==upr+1 || (pPage->intKey && !pPage->leaf) );
assert( pPage->isInit );
if( pPage->leaf ){
- assert( pCur->aiIdx[pCur->iPage]<pCur->apPage[pCur->iPage]->nCell );
+ assert( pCur->aiIdx[pCur->iPage]<pCur->pPage->nCell );
pCur->aiIdx[pCur->iPage] = (u16)idx;
*pRes = c;
rc = SQLITE_OK;
@@ -5076,7 +5097,7 @@
}
}
- pPage = pCur->apPage[pCur->iPage];
+ pPage = pCur->pPage;
idx = ++pCur->aiIdx[pCur->iPage];
assert( pPage->isInit );
@@ -5100,7 +5121,7 @@
return SQLITE_OK;
}
moveToParent(pCur);
- pPage = pCur->apPage[pCur->iPage];
+ pPage = pCur->pPage;
}while( pCur->aiIdx[pCur->iPage]>=pPage->nCell );
if( pPage->intKey ){
return sqlite3BtreeNext(pCur, pRes);
@@ -5124,7 +5145,7 @@
pCur->curFlags &= ~(BTCF_ValidNKey|BTCF_ValidOvfl);
*pRes = 0;
if( pCur->eState!=CURSOR_VALID ) return btreeNext(pCur, pRes);
- pPage = pCur->apPage[pCur->iPage];
+ pPage = pCur->pPage;
if( (++pCur->aiIdx[pCur->iPage])>=pPage->nCell ){
pCur->aiIdx[pCur->iPage]--;
return btreeNext(pCur, pRes);
@@ -5187,7 +5208,8 @@
}
}
- pPage = pCur->apPage[pCur->iPage];
+ pPage = pCur->pPage;
+ assert( pPage==pCur->apPage[pCur->iPage] );
assert( pPage->isInit );
if( !pPage->leaf ){
int idx = pCur->aiIdx[pCur->iPage];
@@ -5207,7 +5229,8 @@
assert( (pCur->curFlags & (BTCF_ValidNKey|BTCF_ValidOvfl))==0 );
pCur->aiIdx[pCur->iPage]--;
- pPage = pCur->apPage[pCur->iPage];
+ assert( pCur->apPage[pCur->iPage]==pCur->pPage );
+ pPage = pCur->pPage;
if( pPage->intKey && !pPage->leaf ){
rc = sqlite3BtreePrevious(pCur, pRes);
}else{
@@ -5226,7 +5249,7 @@
pCur->info.nSize = 0;
if( pCur->eState!=CURSOR_VALID
|| pCur->aiIdx[pCur->iPage]==0
- || pCur->apPage[pCur->iPage]->leaf==0
+ || pCur->pPage->leaf==0
){
return btreePrevious(pCur, pRes);
}
@@ -7419,7 +7442,8 @@
do {
int iPage = pCur->iPage;
- MemPage *pPage = pCur->apPage[iPage];
+ MemPage *pPage = pCur->pPage;
+ assert( pPage==pCur->apPage[iPage] );
if( iPage==0 ){
if( pPage->nOverflow ){
@@ -7434,7 +7458,8 @@
pCur->iPage = 1;
pCur->aiIdx[0] = 0;
pCur->aiIdx[1] = 0;
- assert( pCur->apPage[1]->nOverflow );
+ pCur->pPage = pCur->apPage[1];
+ assert( pCur->pPage->nOverflow );
}
}else{
break;
@@ -7513,6 +7538,7 @@
releasePage(pPage);
pCur->iPage--;
assert( pCur->iPage>=0 );
+ pCur->pPage = pCur->apPage[pCur->iPage];
}
}while( rc==SQLITE_OK );
@@ -7615,7 +7641,8 @@
}
assert( pCur->eState==CURSOR_VALID || (pCur->eState==CURSOR_INVALID && loc) );
- pPage = pCur->apPage[pCur->iPage];
+ assert( pCur->pPage==pCur->apPage[pCur->iPage] );
+ pPage = pCur->pPage;
assert( pPage->intKey || nKey>=0 );
assert( pPage->leaf || !pPage->intKey );
@@ -7682,10 +7709,11 @@
** fails. Internal data structure corruption will result otherwise.
** Also, set the cursor state to invalid. This stops saveCursorPosition()
** from trying to save the current position of the cursor. */
- pCur->apPage[pCur->iPage]->nOverflow = 0;
+ assert( pCur->pPage==pCur->apPage[pCur->iPage] );
+ pCur->pPage->nOverflow = 0;
pCur->eState = CURSOR_INVALID;
}
- assert( pCur->apPage[pCur->iPage]->nOverflow==0 );
+ assert( pCur->pPage->nOverflow==0 );
end_insert:
return rc;
@@ -7711,8 +7739,9 @@
assert( pCur->curFlags & BTCF_WriteFlag );
assert( hasSharedCacheTableLock(p, pCur->pgnoRoot, pCur->pKeyInfo!=0, 2) );
assert( !hasReadConflicts(p, pCur->pgnoRoot) );
+ assert( pCur->pPage==pCur->apPage[pCur->iPage] );
- if( NEVER(pCur->aiIdx[pCur->iPage]>=pCur->apPage[pCur->iPage]->nCell)
+ if( NEVER(pCur->aiIdx[pCur->iPage]>=pCur->pPage->nCell)
|| NEVER(pCur->eState!=CURSOR_VALID)
){
return SQLITE_ERROR; /* Something has gone awry. */
@@ -7762,7 +7791,7 @@
** node. The cell from the leaf node needs to be moved to the internal
** node to replace the deleted cell. */
if( !pPage->leaf ){
- MemPage *pLeaf = pCur->apPage[pCur->iPage];
+ MemPage *pLeaf = pCur->pPage;
int nCell;
Pgno n = pCur->apPage[iCellDepth+1]->pgno;
unsigned char *pTmp;
@@ -7798,6 +7827,7 @@
while( pCur->iPage>iCellDepth ){
releasePage(pCur->apPage[pCur->iPage--]);
}
+ pCur->pPage = pCur->apPage[pCur->iPage];
rc = balance(pCur);
}
@@ -8302,7 +8332,8 @@
** this page contains countable entries. Increment the entry counter
** accordingly.
*/
- pPage = pCur->apPage[pCur->iPage];
+ assert( pCur->pPage==pCur->apPage[pCur->iPage] );
+ pPage = pCur->pPage;
if( pPage->leaf || !pPage->intKey ){
nEntry += pPage->nCell;
}
@@ -8325,10 +8356,11 @@
return moveToRoot(pCur);
}
moveToParent(pCur);
- }while ( pCur->aiIdx[pCur->iPage]>=pCur->apPage[pCur->iPage]->nCell );
+ }while ( pCur->aiIdx[pCur->iPage]>=pCur->pPage->nCell );
pCur->aiIdx[pCur->iPage]++;
- pPage = pCur->apPage[pCur->iPage];
+ assert( pCur->pPage==pCur->apPage[pCur->iPage] );
+ pPage = pCur->pPage;
}
/* Descend to the child node of the cell that the cursor currently
@@ -9111,6 +9143,7 @@
assert( hasSharedCacheTableLock(pCsr->pBtree, pCsr->pgnoRoot, 0, 2) );
assert( !hasReadConflicts(pCsr->pBtree, pCsr->pgnoRoot) );
assert( pCsr->apPage[pCsr->iPage]->intKey );
+ assert( pCsr->pPage==pCsr->apPage[pCsr->iPage] );
return accessPayload(pCsr, offset, amt, (unsigned char *)z, 1);
}
diff --git a/src/btreeInt.h b/src/btreeInt.h
index 33ef641..d457832 100644
--- a/src/btreeInt.h
+++ b/src/btreeInt.h
@@ -518,6 +518,7 @@
u8 hints; /* As configured by CursorSetHints() */
i16 iPage; /* Index of current page in apPage */
u16 aiIdx[BTCURSOR_MAX_DEPTH]; /* Current index in apPage[i] */
+ MemPage *pPage; /* Current page */
MemPage *apPage[BTCURSOR_MAX_DEPTH]; /* Pages from root to current page */
};
