/* Forward declaration required by incrVacuumStep(). */
static int allocateBtreePage(BtShared *, MemPage **, Pgno *, Pgno, u8);
+#define BTALLOC_ANY 0 /* Allocate any page */
+#define BTALLOC_EXACT 1 /* Allocate exact page if possible */
+#define BTALLOC_LE 2 /* Allocate any page <= the parameter */
/*
-** Perform a single step of an incremental-vacuum. If successful,
-** return SQLITE_OK. If there is no work to do (and therefore no
-** point in calling this function again), return SQLITE_DONE.
+** Perform a single step of an incremental-vacuum. If successful, return
+** SQLITE_OK. If there is no work to do (and therefore no point in
+** calling this function again), return SQLITE_DONE. Or, if an error
+** occurs, return some other error code.
**
-** More specificly, this function attempts to re-organize the
-** database so that the last page of the file currently in use
-** is no longer in use.
+** More specificly, this function attempts to re-organize the database so
+** that the last page of the file currently in use is no longer in use.
**
-** If the nFin parameter is non-zero, this function assumes
-** that the caller will keep calling incrVacuumStep() until
-** it returns SQLITE_DONE or an error, and that nFin is the
-** number of pages the database file will contain after this
-** process is complete. If nFin is zero, it is assumed that
-** incrVacuumStep() will be called a finite amount of times
-** which may or may not empty the freelist. A full autovacuum
-** has nFin>0. A "PRAGMA incremental_vacuum" has nFin==0.
+** Parameter nFin is the number of pages that this database would contain
+** were this function called until it returns SQLITE_DONE.
+**
+** If the bCommit parameter is non-zero, this function assumes that the
+** caller will keep calling incrVacuumStep() until it returns SQLITE_DONE
+** or an error. bCommit is passed true for an auto-vacuum-on-commmit
+** operation, or false for an incremental vacuum.
*/
-static int incrVacuumStep(BtShared *pBt, Pgno nFin, Pgno iLastPg){
+static int incrVacuumStep(BtShared *pBt, Pgno nFin, Pgno iLastPg, int bCommit){
Pgno nFreeList; /* Number of pages still on the free-list */
int rc;
}
if( eType==PTRMAP_FREEPAGE ){
- if( nFin==0 ){
+ if( bCommit==0 ){
/* Remove the page from the files free-list. This is not required
- ** if nFin is non-zero. In that case, the free-list will be
+ ** if bCommit is non-zero. In that case, the free-list will be
** truncated to zero after this function returns, so it doesn't
** matter if it still contains some garbage entries.
*/
Pgno iFreePg;
MemPage *pFreePg;
- rc = allocateBtreePage(pBt, &pFreePg, &iFreePg, iLastPg, 1);
+ rc = allocateBtreePage(pBt, &pFreePg, &iFreePg, iLastPg, BTALLOC_EXACT);
if( rc!=SQLITE_OK ){
return rc;
}
} else {
Pgno iFreePg; /* Index of free page to move pLastPg to */
MemPage *pLastPg;
+ u8 eMode = BTALLOC_ANY; /* Mode parameter for allocateBtreePage() */
+ Pgno iNear = 0; /* nearby parameter for allocateBtreePage() */
rc = btreeGetPage(pBt, iLastPg, &pLastPg, 0);
if( rc!=SQLITE_OK ){
return rc;
}
- /* If nFin is zero, this loop runs exactly once and page pLastPg
+ /* If bCommit is zero, this loop runs exactly once and page pLastPg
** is swapped with the first free page pulled off the free list.
**
- ** On the other hand, if nFin is greater than zero, then keep
+ ** On the other hand, if bCommit is greater than zero, then keep
** looping until a free-page located within the first nFin pages
** of the file is found.
*/
+ if( bCommit==0 ){
+ eMode = BTALLOC_LE;
+ iNear = nFin;
+ }
do {
MemPage *pFreePg;
- rc = allocateBtreePage(pBt, &pFreePg, &iFreePg, 0, 0);
+ rc = allocateBtreePage(pBt, &pFreePg, &iFreePg, iNear, eMode);
if( rc!=SQLITE_OK ){
releasePage(pLastPg);
return rc;
}
releasePage(pFreePg);
- }while( nFin!=0 && iFreePg>nFin );
+ }while( bCommit && iFreePg>nFin );
assert( iFreePg<iLastPg );
rc = sqlite3PagerWrite(pLastPg->pDbPage);
}
}
- if( nFin==0 ){
+ if( bCommit==0 ){
iLastPg--;
while( iLastPg==PENDING_BYTE_PAGE(pBt)||PTRMAP_ISPAGE(pBt, iLastPg) ){
if( PTRMAP_ISPAGE(pBt, iLastPg) ){
return SQLITE_OK;
}
+/*
+** The database opened by the first argument is an auto-vacuum database
+** nOrig pages in size containing nFree free pages. Return the expected
+** size of the database in pages following an auto-vacuum operation.
+*/
+static Pgno finalDbSize(BtShared *pBt, Pgno nOrig, Pgno nFree){
+ int nEntry; /* Number of entries on one ptrmap page */
+ Pgno nPtrmap; /* Number of PtrMap pages to be freed */
+ Pgno nFin; /* Return value */
+
+ nEntry = pBt->usableSize/5;
+ nPtrmap = (nFree-nOrig+PTRMAP_PAGENO(pBt, nOrig)+nEntry)/nEntry;
+ nFin = nOrig - nFree - nPtrmap;
+ if( nOrig>PENDING_BYTE_PAGE(pBt) && nFin<PENDING_BYTE_PAGE(pBt) ){
+ nFin--;
+ }
+ while( PTRMAP_ISPAGE(pBt, nFin) || nFin==PENDING_BYTE_PAGE(pBt) ){
+ nFin--;
+ }
+ if( nFin>nOrig ) return SQLITE_CORRUPT_BKPT;
+
+ return nFin;
+}
+
/*
** A write-transaction must be opened before calling this function.
** It performs a single unit of work towards an incremental vacuum.
if( !pBt->autoVacuum ){
rc = SQLITE_DONE;
}else{
- invalidateAllOverflowCache(pBt);
- rc = incrVacuumStep(pBt, 0, btreePagecount(pBt));
- if( rc==SQLITE_OK ){
- rc = sqlite3PagerWrite(pBt->pPage1->pDbPage);
- put4byte(&pBt->pPage1->aData[28], pBt->nPage);
+ Pgno nOrig = btreePagecount(pBt);
+ Pgno nFree = get4byte(&pBt->pPage1->aData[36]);
+ Pgno nFin = finalDbSize(pBt, nOrig, nFree);
+
+ if( nFin<nOrig ){
+ invalidateAllOverflowCache(pBt);
+ rc = incrVacuumStep(pBt, nFin, nOrig, 0);
+ if( rc==SQLITE_OK ){
+ rc = sqlite3PagerWrite(pBt->pPage1->pDbPage);
+ put4byte(&pBt->pPage1->aData[28], pBt->nPage);
+ }
+ }else{
+ rc = SQLITE_DONE;
}
}
sqlite3BtreeLeave(p);
if( !pBt->incrVacuum ){
Pgno nFin; /* Number of pages in database after autovacuuming */
Pgno nFree; /* Number of pages on the freelist initially */
- Pgno nPtrmap; /* Number of PtrMap pages to be freed */
Pgno iFree; /* The next page to be freed */
- int nEntry; /* Number of entries on one ptrmap page */
Pgno nOrig; /* Database size before freeing */
nOrig = btreePagecount(pBt);
}
nFree = get4byte(&pBt->pPage1->aData[36]);
- nEntry = pBt->usableSize/5;
- nPtrmap = (nFree-nOrig+PTRMAP_PAGENO(pBt, nOrig)+nEntry)/nEntry;
- nFin = nOrig - nFree - nPtrmap;
- if( nOrig>PENDING_BYTE_PAGE(pBt) && nFin<PENDING_BYTE_PAGE(pBt) ){
- nFin--;
- }
- while( PTRMAP_ISPAGE(pBt, nFin) || nFin==PENDING_BYTE_PAGE(pBt) ){
- nFin--;
- }
+ nFin = finalDbSize(pBt, nOrig, nFree);
if( nFin>nOrig ) return SQLITE_CORRUPT_BKPT;
for(iFree=nOrig; iFree>nFin && rc==SQLITE_OK; iFree--){
- rc = incrVacuumStep(pBt, nFin, iFree);
+ rc = incrVacuumStep(pBt, nFin, iFree, 1);
}
if( (rc==SQLITE_DONE || rc==SQLITE_OK) && nFree>0 ){
rc = sqlite3PagerWrite(pBt->pPage1->pDbPage);
MemPage **ppPage,
Pgno *pPgno,
Pgno nearby,
- u8 exact
+ u8 eMode
){
MemPage *pPage1;
int rc;
** the entire-list will be searched for that page.
*/
#ifndef SQLITE_OMIT_AUTOVACUUM
- if( exact && nearby<=mxPage ){
- u8 eType;
- assert( nearby>0 );
- assert( pBt->autoVacuum );
- rc = ptrmapGet(pBt, nearby, &eType, 0);
- if( rc ) return rc;
- if( eType==PTRMAP_FREEPAGE ){
- searchList = 1;
+ if( eMode==BTALLOC_EXACT ){
+ if( nearby<=mxPage ){
+ u8 eType;
+ assert( nearby>0 );
+ assert( pBt->autoVacuum );
+ rc = ptrmapGet(pBt, nearby, &eType, 0);
+ if( rc ) return rc;
+ if( eType==PTRMAP_FREEPAGE ){
+ searchList = 1;
+ }
}
- *pPgno = nearby;
+ }else if( eMode==BTALLOC_LE ){
+ searchList = 1;
}
#endif
rc = SQLITE_CORRUPT_BKPT;
goto end_allocate_page;
#ifndef SQLITE_OMIT_AUTOVACUUM
- }else if( searchList && nearby==iTrunk ){
+ }else if( searchList
+ && (nearby==iTrunk || (iTrunk<nearby && eMode==BTALLOC_LE))
+ ){
/* The list is being searched and this trunk page is the page
** to allocate, regardless of whether it has leaves.
*/
- assert( *pPgno==iTrunk );
+ *pPgno = iTrunk;
*ppPage = pTrunk;
searchList = 0;
rc = sqlite3PagerWrite(pTrunk->pDbPage);
goto end_allocate_page;
}
testcase( iPage==mxPage );
- if( !searchList || iPage==nearby ){
+ if( !searchList
+ || (iPage==nearby || (iPage<nearby && eMode==BTALLOC_LE))
+ ){
int noContent;
*pPgno = iPage;
TRACE(("ALLOCATE: %d was leaf %d of %d on trunk %d"
** be moved to the allocated page (unless the allocated page happens
** to reside at pgnoRoot).
*/
- rc = allocateBtreePage(pBt, &pPageMove, &pgnoMove, pgnoRoot, 1);
+ rc = allocateBtreePage(pBt, &pPageMove, &pgnoMove, pgnoRoot, BTALLOC_EXACT);
if( rc!=SQLITE_OK ){
return rc;
}
projects / thirdparty / sqlite.git / commitdiff
