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Overview
Comment: | Remove the "rowid cache" that sought to remember the largest rowid for a table and thereby speed up OP_NewRowid. That cache was ineffective. Removing it results in a performance increase of 0.4%, less memory usage, and a slightly smaller library size. |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | trunk |
Files: | files | file ages | folders |
SHA1: |
56bc5ce8958c8e6250531b4052b905d7 |
User & Date: | drh 2014-02-12 21:31:12.616 |
References
2015-09-30
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12:10 | • New ticket [1b266395d6] INSERT OR REPLACE with a foreign key constraint leads to assertion fault. (artifact: 7f88fd969c user: drh) | |
Context
2014-02-12
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23:52 | Minor simplifications to the "zeroPage()" routine in btree.c. (check-in: cc8f10bcb2 user: drh tags: trunk) | |
21:31 | Remove the "rowid cache" that sought to remember the largest rowid for a table and thereby speed up OP_NewRowid. That cache was ineffective. Removing it results in a performance increase of 0.4%, less memory usage, and a slightly smaller library size. (check-in: 56bc5ce895 user: drh tags: trunk) | |
14:43 | Make sure "rowid" columns are correctly resolved in joins between normal tables and WITHOUT ROWID tables. Fix for ticket [c34d0557f740c45070]. (check-in: 5d01426ddf user: drh tags: trunk) | |
Changes
Changes to src/btree.c.
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3628 3629 3630 3631 3632 3633 3634 | pCur->wrFlag = (u8)wrFlag; pCur->pNext = pBt->pCursor; if( pCur->pNext ){ pCur->pNext->pPrev = pCur; } pBt->pCursor = pCur; pCur->eState = CURSOR_INVALID; | < | 3628 3629 3630 3631 3632 3633 3634 3635 3636 3637 3638 3639 3640 3641 | pCur->wrFlag = (u8)wrFlag; pCur->pNext = pBt->pCursor; if( pCur->pNext ){ pCur->pNext->pPrev = pCur; } pBt->pCursor = pCur; pCur->eState = CURSOR_INVALID; return SQLITE_OK; } int sqlite3BtreeCursor( Btree *p, /* The btree */ int iTable, /* Root page of table to open */ int wrFlag, /* 1 to write. 0 read-only */ struct KeyInfo *pKeyInfo, /* First arg to xCompare() */ |
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3669 3670 3671 3672 3673 3674 3675 | ** do not need to be zeroed and they are large, so we can save a lot ** of run-time by skipping the initialization of those elements. */ void sqlite3BtreeCursorZero(BtCursor *p){ memset(p, 0, offsetof(BtCursor, iPage)); } | < < < < < < < < < < < < < < < < < < < < < < < < < < < < < < | 3668 3669 3670 3671 3672 3673 3674 3675 3676 3677 3678 3679 3680 3681 | ** do not need to be zeroed and they are large, so we can save a lot ** of run-time by skipping the initialization of those elements. */ void sqlite3BtreeCursorZero(BtCursor *p){ memset(p, 0, offsetof(BtCursor, iPage)); } /* ** Close a cursor. The read lock on the database file is released ** when the last cursor is closed. */ int sqlite3BtreeCloseCursor(BtCursor *pCur){ Btree *pBtree = pCur->pBtree; if( pBtree ){ |
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6982 6983 6984 6985 6986 6987 6988 | ** that the cursor is already where it needs to be and returns without ** doing any work. To avoid thwarting these optimizations, it is important ** not to clear the cursor here. */ rc = saveAllCursors(pBt, pCur->pgnoRoot, pCur); if( rc ) return rc; | > | | < < > > > > > > > | 6951 6952 6953 6954 6955 6956 6957 6958 6959 6960 6961 6962 6963 6964 6965 6966 6967 6968 6969 6970 6971 6972 6973 6974 6975 | ** that the cursor is already where it needs to be and returns without ** doing any work. To avoid thwarting these optimizations, it is important ** not to clear the cursor here. */ rc = saveAllCursors(pBt, pCur->pgnoRoot, pCur); if( rc ) return rc; if( pCur->pKeyInfo==0 ){ /* If this is an insert into a table b-tree, invalidate any incrblob ** cursors open on the row being replaced */ invalidateIncrblobCursors(p, nKey, 0); /* If the cursor is currently on the last row and we are appending a ** new row onto the end, set the "loc" to avoid an unnecessary btreeMoveto() ** call */ if( pCur->validNKey && nKey>0 && pCur->info.nKey==nKey-1 ){ loc = -1; } } if( !loc ){ rc = btreeMoveto(pCur, pKey, nKey, appendBias, &loc); if( rc ) return rc; } assert( pCur->eState==CURSOR_VALID || (pCur->eState==CURSOR_INVALID && loc) ); |
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7056 7057 7058 7059 7060 7061 7062 | ** is advantageous to leave the cursor pointing to the last entry in ** the b-tree if possible. If the cursor is left pointing to the last ** entry in the table, and the next row inserted has an integer key ** larger than the largest existing key, it is possible to insert the ** row without seeking the cursor. This can be a big performance boost. */ pCur->info.nSize = 0; | < > | 7031 7032 7033 7034 7035 7036 7037 7038 7039 7040 7041 7042 7043 7044 7045 7046 | ** is advantageous to leave the cursor pointing to the last entry in ** the b-tree if possible. If the cursor is left pointing to the last ** entry in the table, and the next row inserted has an integer key ** larger than the largest existing key, it is possible to insert the ** row without seeking the cursor. This can be a big performance boost. */ pCur->info.nSize = 0; if( rc==SQLITE_OK && pPage->nOverflow ){ pCur->validNKey = 0; rc = balance(pCur); /* Must make sure nOverflow is reset to zero even if the balance() ** 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; |
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Changes to src/btree.h.
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178 179 180 181 182 183 184 | int sqlite3BtreePrevious(BtCursor*, int *pRes); int sqlite3BtreeKeySize(BtCursor*, i64 *pSize); int sqlite3BtreeKey(BtCursor*, u32 offset, u32 amt, void*); const void *sqlite3BtreeKeyFetch(BtCursor*, u32 *pAmt); const void *sqlite3BtreeDataFetch(BtCursor*, u32 *pAmt); int sqlite3BtreeDataSize(BtCursor*, u32 *pSize); int sqlite3BtreeData(BtCursor*, u32 offset, u32 amt, void*); | < < | 178 179 180 181 182 183 184 185 186 187 188 189 190 191 | int sqlite3BtreePrevious(BtCursor*, int *pRes); int sqlite3BtreeKeySize(BtCursor*, i64 *pSize); int sqlite3BtreeKey(BtCursor*, u32 offset, u32 amt, void*); const void *sqlite3BtreeKeyFetch(BtCursor*, u32 *pAmt); const void *sqlite3BtreeDataFetch(BtCursor*, u32 *pAmt); int sqlite3BtreeDataSize(BtCursor*, u32 *pSize); int sqlite3BtreeData(BtCursor*, u32 offset, u32 amt, void*); char *sqlite3BtreeIntegrityCheck(Btree*, int *aRoot, int nRoot, int, int*); struct Pager *sqlite3BtreePager(Btree*); int sqlite3BtreePutData(BtCursor*, u32 offset, u32 amt, void*); void sqlite3BtreeCacheOverflow(BtCursor *); void sqlite3BtreeClearCursor(BtCursor *); |
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Changes to src/btreeInt.h.
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496 497 498 499 500 501 502 | BtShared *pBt; /* The BtShared this cursor points to */ BtCursor *pNext, *pPrev; /* Forms a linked list of all cursors */ struct KeyInfo *pKeyInfo; /* Argument passed to comparison function */ #ifndef SQLITE_OMIT_INCRBLOB Pgno *aOverflow; /* Cache of overflow page locations */ #endif Pgno pgnoRoot; /* The root page of this tree */ | < | 496 497 498 499 500 501 502 503 504 505 506 507 508 509 | BtShared *pBt; /* The BtShared this cursor points to */ BtCursor *pNext, *pPrev; /* Forms a linked list of all cursors */ struct KeyInfo *pKeyInfo; /* Argument passed to comparison function */ #ifndef SQLITE_OMIT_INCRBLOB Pgno *aOverflow; /* Cache of overflow page locations */ #endif Pgno pgnoRoot; /* The root page of this tree */ CellInfo info; /* A parse of the cell we are pointing at */ i64 nKey; /* Size of pKey, or last integer key */ void *pKey; /* Saved key that was cursor's last known position */ int skipNext; /* Prev() is noop if negative. Next() is noop if positive */ u8 wrFlag; /* True if writable */ u8 atLast; /* Cursor pointing to the last entry */ u8 validNKey; /* True if info.nKey is valid */ |
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Changes to src/vdbe.c.
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3830 3831 3832 3833 3834 3835 3836 | ** Others complain about 0x7ffffffffffffffffLL. The following macro seems ** to provide the constant while making all compilers happy. */ # define MAX_ROWID (i64)( (((u64)0x7fffffff)<<32) | (u64)0xffffffff ) #endif if( !pC->useRandomRowid ){ | < < | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | < < < | 3830 3831 3832 3833 3834 3835 3836 3837 3838 3839 3840 3841 3842 3843 3844 3845 3846 3847 3848 3849 3850 3851 3852 3853 3854 3855 3856 3857 3858 3859 3860 3861 3862 3863 3864 3865 3866 3867 3868 3869 3870 3871 3872 3873 3874 3875 3876 3877 3878 3879 3880 3881 3882 3883 3884 3885 3886 3887 3888 3889 3890 3891 | ** Others complain about 0x7ffffffffffffffffLL. The following macro seems ** to provide the constant while making all compilers happy. */ # define MAX_ROWID (i64)( (((u64)0x7fffffff)<<32) | (u64)0xffffffff ) #endif if( !pC->useRandomRowid ){ rc = sqlite3BtreeLast(pC->pCursor, &res); if( rc!=SQLITE_OK ){ goto abort_due_to_error; } if( res ){ v = 1; /* IMP: R-61914-48074 */ }else{ assert( sqlite3BtreeCursorIsValid(pC->pCursor) ); rc = sqlite3BtreeKeySize(pC->pCursor, &v); assert( rc==SQLITE_OK ); /* Cannot fail following BtreeLast() */ if( v>=MAX_ROWID ){ pC->useRandomRowid = 1; }else{ v++; /* IMP: R-29538-34987 */ } } } #ifndef SQLITE_OMIT_AUTOINCREMENT if( pOp->p3 ){ /* Assert that P3 is a valid memory cell. */ assert( pOp->p3>0 ); if( p->pFrame ){ for(pFrame=p->pFrame; pFrame->pParent; pFrame=pFrame->pParent); /* Assert that P3 is a valid memory cell. */ assert( pOp->p3<=pFrame->nMem ); pMem = &pFrame->aMem[pOp->p3]; }else{ /* Assert that P3 is a valid memory cell. */ assert( pOp->p3<=(p->nMem-p->nCursor) ); pMem = &aMem[pOp->p3]; memAboutToChange(p, pMem); } assert( memIsValid(pMem) ); REGISTER_TRACE(pOp->p3, pMem); sqlite3VdbeMemIntegerify(pMem); assert( (pMem->flags & MEM_Int)!=0 ); /* mem(P3) holds an integer */ if( pMem->u.i==MAX_ROWID || pC->useRandomRowid ){ rc = SQLITE_FULL; /* IMP: R-12275-61338 */ goto abort_due_to_error; } if( v<pMem->u.i+1 ){ v = pMem->u.i + 1; } pMem->u.i = v; } #endif if( pC->useRandomRowid ){ /* IMPLEMENTATION-OF: R-07677-41881 If the largest ROWID is equal to the ** largest possible integer (9223372036854775807) then the database ** engine starts picking positive candidate ROWIDs at random until ** it finds one that is not previously used. */ assert( pOp->p3==0 ); /* We cannot be in random rowid mode if this is ** an AUTOINCREMENT table. */ |
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4016 4017 4018 4019 4020 4021 4022 | } seekResult = ((pOp->p5 & OPFLAG_USESEEKRESULT) ? pC->seekResult : 0); if( pData->flags & MEM_Zero ){ nZero = pData->u.nZero; }else{ nZero = 0; } | < | 4011 4012 4013 4014 4015 4016 4017 4018 4019 4020 4021 4022 4023 4024 | } seekResult = ((pOp->p5 & OPFLAG_USESEEKRESULT) ? pC->seekResult : 0); if( pData->flags & MEM_Zero ){ nZero = pData->u.nZero; }else{ nZero = 0; } rc = sqlite3BtreeInsert(pC->pCursor, 0, iKey, pData->z, pData->n, nZero, (pOp->p5 & OPFLAG_APPEND)!=0, seekResult ); pC->rowidIsValid = 0; pC->deferredMoveto = 0; pC->cacheStatus = CACHE_STALE; |
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4078 4079 4080 4081 4082 4083 4084 | ** below is always a no-op and cannot fail. We will run it anyhow, though, ** to guard against future changes to the code generator. **/ assert( pC->deferredMoveto==0 ); rc = sqlite3VdbeCursorMoveto(pC); if( NEVER(rc!=SQLITE_OK) ) goto abort_due_to_error; | < | 4072 4073 4074 4075 4076 4077 4078 4079 4080 4081 4082 4083 4084 4085 | ** below is always a no-op and cannot fail. We will run it anyhow, though, ** to guard against future changes to the code generator. **/ assert( pC->deferredMoveto==0 ); rc = sqlite3VdbeCursorMoveto(pC); if( NEVER(rc!=SQLITE_OK) ) goto abort_due_to_error; rc = sqlite3BtreeDelete(pC->pCursor); pC->cacheStatus = CACHE_STALE; /* Invoke the update-hook if required. */ if( rc==SQLITE_OK && db->xUpdateCallback && pOp->p4.z && pC->isTable ){ db->xUpdateCallback(db->pUpdateArg, SQLITE_DELETE, db->aDb[pC->iDb].zName, pOp->p4.z, iKey); |
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