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Overview
Comment: | Add the MemPage.noPayload boolean and use it to help cellSizePtr() and btreeParseCellPtr() run faster. |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | trunk |
Files: | files | file ages | folders |
SHA1: |
8e3375313ebbf26b68561f3ed31d2a48 |
User & Date: | drh 2014-09-24 00:59:08.082 |
Context
2014-09-24
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01:23 | Shorten all lines of source code in btree.c to at most 80 characters. No logical changes. (check-in: 5dd41cdbfe user: drh tags: trunk) | |
00:59 | Add the MemPage.noPayload boolean and use it to help cellSizePtr() and btreeParseCellPtr() run faster. (check-in: 8e3375313e user: drh tags: trunk) | |
2014-09-23
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23:12 | Remove an unused C-preprocessor macro. No functional changes to the code. (check-in: f480582cca user: drh tags: trunk) | |
Changes
Changes to src/btree.c.
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970 971 972 973 974 975 976 | ** takes a pointer to the body of the cell as its second argument. */ static void btreeParseCellPtr( MemPage *pPage, /* Page containing the cell */ u8 *pCell, /* Pointer to the cell text. */ CellInfo *pInfo /* Fill in this structure */ ){ | | | | | | | > > | < | > > > > | 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992 993 994 995 996 997 998 999 1000 1001 1002 | ** takes a pointer to the body of the cell as its second argument. */ static void btreeParseCellPtr( MemPage *pPage, /* Page containing the cell */ u8 *pCell, /* Pointer to the cell text. */ CellInfo *pInfo /* Fill in this structure */ ){ u8 *pIter; /* For scanning through pCell */ u32 nPayload; /* Number of bytes of cell payload */ assert( sqlite3_mutex_held(pPage->pBt->mutex) ); assert( pPage->leaf==0 || pPage->leaf==1 ); if( pPage->intKeyLeaf ){ assert( pPage->childPtrSize==0 ); pIter = pCell + getVarint32(pCell, nPayload); pIter += getVarint(pIter, (u64*)&pInfo->nKey); }else if( pPage->noPayload ){ assert( pPage->childPtrSize==4 ); pInfo->nSize = 4 + getVarint(&pCell[4], (u64*)&pInfo->nKey); pInfo->nPayload = 0; pInfo->nLocal = 0; pInfo->iOverflow = 0; pInfo->pPayload = 0; return; }else{ pIter = pCell + pPage->childPtrSize; pIter += getVarint32(pIter, nPayload); pInfo->nKey = nPayload; } pInfo->nPayload = nPayload; pInfo->pPayload = pIter; testcase( nPayload==pPage->maxLocal ); testcase( nPayload==pPage->maxLocal+1 ); |
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1042 1043 1044 1045 1046 1047 1048 | /* ** Compute the total number of bytes that a Cell needs in the cell ** data area of the btree-page. The return number includes the cell ** data header and the local payload, but not any overflow page or ** the space used by the cell pointer. */ static u16 cellSizePtr(MemPage *pPage, u8 *pCell){ | | | | | > > > > > | | | | | | | | | < < < < | > > > | < < < < < < < | 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 | /* ** Compute the total number of bytes that a Cell needs in the cell ** data area of the btree-page. The return number includes the cell ** data header and the local payload, but not any overflow page or ** the space used by the cell pointer. */ static u16 cellSizePtr(MemPage *pPage, u8 *pCell){ u8 *pIter = pCell + pPage->childPtrSize; /* For looping over bytes of pCell */ u8 *pEnd; /* End mark for a varint */ u32 nSize; /* Size value to return */ #ifdef SQLITE_DEBUG /* The value returned by this function should always be the same as ** the (CellInfo.nSize) value found by doing a full parse of the ** cell. If SQLITE_DEBUG is defined, an assert() at the bottom of ** this function verifies that this invariant is not violated. */ CellInfo debuginfo; btreeParseCellPtr(pPage, pCell, &debuginfo); #endif if( pPage->noPayload ){ pEnd = &pIter[9]; while( (*pIter++)&0x80 && pIter<pEnd ); assert( pPage->childPtrSize==4 ); return (u16)(pIter - pCell); } nSize = *pIter; if( nSize>=0x80 ){ pEnd = &pIter[9]; nSize &= 0x7f; do{ nSize = (nSize<<7) | (*++pIter & 0x7f); }while( *(pIter)>=0x80 && pIter<pEnd ); } pIter++; if( pPage->intKey ){ /* pIter now points at the 64-bit integer key value, a variable length ** integer. The following block moves pIter to point at the first byte ** past the end of the key value. */ pEnd = &pIter[9]; while( (*pIter++)&0x80 && pIter<pEnd ); } testcase( nSize==pPage->maxLocal ); testcase( nSize==pPage->maxLocal+1 ); if( nSize<=pPage->maxLocal ){ nSize += (u32)(pIter - pCell); if( nSize<4 ) nSize = 4; }else{ int minLocal = pPage->minLocal; nSize = minLocal + (nSize - minLocal) % (pPage->pBt->usableSize - 4); testcase( nSize==pPage->maxLocal ); testcase( nSize==pPage->maxLocal+1 ); if( nSize>pPage->maxLocal ){ nSize = minLocal; } nSize += 4 + (u16)(pIter - pCell); } assert( nSize==debuginfo.nSize || CORRUPT_DB ); return (u16)nSize; } #ifdef SQLITE_DEBUG /* This variation on cellSizePtr() is used inside of assert() statements ** only. */ |
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1438 1439 1440 1441 1442 1443 1444 | assert( sqlite3_mutex_held(pPage->pBt->mutex) ); pPage->leaf = (u8)(flagByte>>3); assert( PTF_LEAF == 1<<3 ); flagByte &= ~PTF_LEAF; pPage->childPtrSize = 4-4*pPage->leaf; pBt = pPage->pBt; if( flagByte==(PTF_LEAFDATA | PTF_INTKEY) ){ pPage->intKey = 1; | | > | > | 1440 1441 1442 1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 1458 1459 1460 1461 | assert( sqlite3_mutex_held(pPage->pBt->mutex) ); pPage->leaf = (u8)(flagByte>>3); assert( PTF_LEAF == 1<<3 ); flagByte &= ~PTF_LEAF; pPage->childPtrSize = 4-4*pPage->leaf; pBt = pPage->pBt; if( flagByte==(PTF_LEAFDATA | PTF_INTKEY) ){ pPage->intKey = 1; pPage->intKeyLeaf = pPage->leaf; pPage->noPayload = !pPage->leaf; pPage->maxLocal = pBt->maxLeaf; pPage->minLocal = pBt->minLeaf; }else if( flagByte==PTF_ZERODATA ){ pPage->intKey = 0; pPage->intKeyLeaf = 0; pPage->noPayload = 0; pPage->maxLocal = pBt->maxLocal; pPage->minLocal = pBt->minLocal; }else{ return SQLITE_CORRUPT_BKPT; } pPage->max1bytePayload = pBt->max1bytePayload; return SQLITE_OK; |
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3851 3852 3853 3854 3855 3856 3857 | ** Failure is not possible. This function always returns SQLITE_OK. ** It might just as well be a procedure (returning void) but we continue ** to return an integer result code for historical reasons. */ int sqlite3BtreeDataSize(BtCursor *pCur, u32 *pSize){ assert( cursorHoldsMutex(pCur) ); assert( pCur->eState==CURSOR_VALID ); | | | 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864 3865 3866 3867 3868 3869 | ** Failure is not possible. This function always returns SQLITE_OK. ** It might just as well be a procedure (returning void) but we continue ** to return an integer result code for historical reasons. */ int sqlite3BtreeDataSize(BtCursor *pCur, u32 *pSize){ assert( cursorHoldsMutex(pCur) ); assert( pCur->eState==CURSOR_VALID ); assert( pCur->apPage[pCur->iPage]->intKeyLeaf==1 ); getCellInfo(pCur); *pSize = pCur->info.nPayload; return SQLITE_OK; } /* ** Given the page number of an overflow page in the database (parameter |
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4686 4687 4688 4689 4690 4691 4692 | assert( biasRight==0 || biasRight==1 ); idx = upr>>(1-biasRight); /* idx = biasRight ? upr : (lwr+upr)/2; */ pCur->aiIdx[pCur->iPage] = (u16)idx; if( xRecordCompare==0 ){ for(;;){ i64 nCellKey; pCell = findCell(pPage, idx) + pPage->childPtrSize; | | | 4690 4691 4692 4693 4694 4695 4696 4697 4698 4699 4700 4701 4702 4703 4704 | assert( biasRight==0 || biasRight==1 ); idx = upr>>(1-biasRight); /* idx = biasRight ? upr : (lwr+upr)/2; */ pCur->aiIdx[pCur->iPage] = (u16)idx; if( xRecordCompare==0 ){ for(;;){ i64 nCellKey; pCell = findCell(pPage, idx) + pPage->childPtrSize; if( pPage->intKeyLeaf ){ while( 0x80 <= *(pCell++) ){ if( pCell>=pPage->aDataEnd ) return SQLITE_CORRUPT_BKPT; } } getVarint(pCell, (u64*)&nCellKey); if( nCellKey<intKey ){ lwr = idx+1; |
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5613 5614 5615 5616 5617 5618 5619 | ** buffer space that is separate from the pPage buffer area */ assert( pCell<pPage->aData || pCell>=&pPage->aData[pBt->pageSize] || sqlite3PagerIswriteable(pPage->pDbPage) ); /* Fill in the header. */ nHeader = pPage->childPtrSize; nPayload = nData + nZero; | | < | 5617 5618 5619 5620 5621 5622 5623 5624 5625 5626 5627 5628 5629 5630 5631 | ** buffer space that is separate from the pPage buffer area */ assert( pCell<pPage->aData || pCell>=&pPage->aData[pBt->pageSize] || sqlite3PagerIswriteable(pPage->pDbPage) ); /* Fill in the header. */ nHeader = pPage->childPtrSize; nPayload = nData + nZero; if( pPage->intKeyLeaf ){ nHeader += putVarint32(&pCell[nHeader], nPayload); }else{ assert( nData==0 ); assert( nZero==0 ); } nHeader += putVarint(&pCell[nHeader], *(u64*)&nKey); |
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6387 6388 6389 6390 6391 6392 6393 | ** apCell[] include child pointers. Either way, all cells in apCell[] ** are alike. ** ** leafCorrection: 4 if pPage is a leaf. 0 if pPage is not a leaf. ** leafData: 1 if pPage holds key+data and pParent holds only keys. */ leafCorrection = apOld[0]->leaf*4; | | | 6390 6391 6392 6393 6394 6395 6396 6397 6398 6399 6400 6401 6402 6403 6404 | ** apCell[] include child pointers. Either way, all cells in apCell[] ** are alike. ** ** leafCorrection: 4 if pPage is a leaf. 0 if pPage is not a leaf. ** leafData: 1 if pPage holds key+data and pParent holds only keys. */ leafCorrection = apOld[0]->leaf*4; leafData = apOld[0]->intKeyLeaf; for(i=0; i<nOld; i++){ int limit; /* Before doing anything else, take a copy of the i'th original sibling ** The rest of this function will use data from the copies rather ** that the original pages since the original pages will be in the ** process of being overwritten. */ |
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6963 6964 6965 6966 6967 6968 6969 | }else{ MemPage * const pParent = pCur->apPage[iPage-1]; int const iIdx = pCur->aiIdx[iPage-1]; rc = sqlite3PagerWrite(pParent->pDbPage); if( rc==SQLITE_OK ){ #ifndef SQLITE_OMIT_QUICKBALANCE | | | 6966 6967 6968 6969 6970 6971 6972 6973 6974 6975 6976 6977 6978 6979 6980 | }else{ MemPage * const pParent = pCur->apPage[iPage-1]; int const iIdx = pCur->aiIdx[iPage-1]; rc = sqlite3PagerWrite(pParent->pDbPage); if( rc==SQLITE_OK ){ #ifndef SQLITE_OMIT_QUICKBALANCE if( pPage->intKeyLeaf && pPage->nOverflow==1 && pPage->aiOvfl[0]==pPage->nCell && pParent->pgno!=1 && pParent->nCell==iIdx ){ /* Call balance_quick() to create a new sibling of pPage on which ** to store the overflow cell. balance_quick() inserts a new cell |
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Changes to src/btreeInt.h.
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269 270 271 272 273 274 275 | ** ** Access to all fields of this structure is controlled by the mutex ** stored in MemPage.pBt->mutex. */ struct MemPage { u8 isInit; /* True if previously initialized. MUST BE FIRST! */ u8 nOverflow; /* Number of overflow cell bodies in aCell[] */ | | > > | < | 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 | ** ** Access to all fields of this structure is controlled by the mutex ** stored in MemPage.pBt->mutex. */ struct MemPage { u8 isInit; /* True if previously initialized. MUST BE FIRST! */ u8 nOverflow; /* Number of overflow cell bodies in aCell[] */ u8 intKey; /* True if table b-trees. False for index b-trees */ u8 intKeyLeaf; /* True if the leaf of an intKey table */ u8 noPayload; /* True if internal intKey page (thus w/o data) */ u8 leaf; /* True if a leaf page */ u8 hdrOffset; /* 100 for page 1. 0 otherwise */ u8 childPtrSize; /* 0 if leaf==1. 4 if leaf==0 */ u8 max1bytePayload; /* min(maxLocal,127) */ u16 maxLocal; /* Copy of BtShared.maxLocal or BtShared.maxLeaf */ u16 minLocal; /* Copy of BtShared.minLocal or BtShared.minLeaf */ u16 cellOffset; /* Index in aData of first cell pointer */ u16 nFree; /* Number of free bytes on the page */ |
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