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Comment and function naming tweaks to pcache. No functionality changes. (CVS 5572)

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FossilOrigin-Name: 4b0e67d397236c740bea88ad3a5912abe896322a
This commit is contained in:
drh
2008-08-20 21:47:45 +00:00
parent 7a4dde7165
commit 41d3027ce8
4 changed files with 75 additions and 63 deletions
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14
manifest
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@@ -1,5 +1,5 @@
C Modify\sthe\slemon\sparser\stemplate\sto\savoid\susing\szero-initialized\sconstants\nwhen\scompiled\swith\sC++.\s\sTicket\s#3288.\s(CVS\s5571) C Comment\sand\sfunction\snaming\stweaks\sto\spcache.\s\sNo\sfunctionality\schanges.\s(CVS\s5572)
D 2008-08-20T17:48:21 D 2008-08-20T21:47:46
F Makefile.arm-wince-mingw32ce-gcc fcd5e9cd67fe88836360bb4f9ef4cb7f8e2fb5a0 F Makefile.arm-wince-mingw32ce-gcc fcd5e9cd67fe88836360bb4f9ef4cb7f8e2fb5a0
F Makefile.in 0b1c022000f55221454a7846022f11674d8024bf F Makefile.in 0b1c022000f55221454a7846022f11674d8024bf
F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -135,10 +135,10 @@ F src/os_common.h 24525d8b7bce66c374dfc1810a6c9043f3359b60
F src/os_os2.c 676ed273b17bd260f905df81375c9f9950d85517 F src/os_os2.c 676ed273b17bd260f905df81375c9f9950d85517
F src/os_unix.c fe0dbc35bcd3de49e46b132abfc0f45d6dd6a864 F src/os_unix.c fe0dbc35bcd3de49e46b132abfc0f45d6dd6a864
F src/os_win.c aefe9ee26430678a19a058a874e4e2bd91398142 F src/os_win.c aefe9ee26430678a19a058a874e4e2bd91398142
F src/pager.c 9f813a8f26680ff510335e2bbd01910b2a77277b F src/pager.c 79d4d33245462c054a7e815e29ec6500c667ef26
F src/pager.h fb9376af5ba8e1eb78ee3b4f15eb0f60658ffd65 F src/pager.h fb9376af5ba8e1eb78ee3b4f15eb0f60658ffd65
F src/parse.y d0f76d2cb8d6883d5600dc20beb961a6022b94b8 F src/parse.y d0f76d2cb8d6883d5600dc20beb961a6022b94b8
F src/pcache.c c1a9abb5e2aa3d1d52a2995c8e0a36535d4d1bc2 F src/pcache.c cf7a7c81366e42330ff9c84d1f3591c905289c3d
F src/pcache.h 71ade7a84ed87d9d20507315260b1d91808d7c9a F src/pcache.h 71ade7a84ed87d9d20507315260b1d91808d7c9a
F src/pragma.c f5b271b090af7fcedd308d7c5807a5503f7a853d F src/pragma.c f5b271b090af7fcedd308d7c5807a5503f7a853d
F src/prepare.c c197041e0c4770672cda75e6bfe10242f885e510 F src/prepare.c c197041e0c4770672cda75e6bfe10242f885e510
@@ -623,7 +623,7 @@ F tool/speedtest16.c c8a9c793df96db7e4933f0852abb7a03d48f2e81
F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
F tool/speedtest8.c 1dbced29de5f59ba2ebf877edcadf171540374d1 F tool/speedtest8.c 1dbced29de5f59ba2ebf877edcadf171540374d1
F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
P aef5b909e960c31527c795bc09a1de846f8afcbb P 71992f4a3723418df5f16093aec92f1f95f0b604
R ba6058aa52b7f536a969626105129ff5 R 1864568c91564440b5d8de8411bca79f
U drh U drh
Z a81a89f6460671859f4d4500f7e3aaad Z 8ae3b66a71a20677fcd2b2a4e9762a73

2
manifest.uuid
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@@ -1 +1 @@
71992f4a3723418df5f16093aec92f1f95f0b604 4b0e67d397236c740bea88ad3a5912abe896322a

7
src/pager.c
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@@ -18,7 +18,7 @@
** file simultaneously, or one process from reading the database while ** file simultaneously, or one process from reading the database while
** another is writing. ** another is writing.
** **
** @(#) $Id: pager.c,v 1.470 2008/08/20 14:49:24 danielk1977 Exp $ ** @(#) $Id: pager.c,v 1.471 2008/08/20 21:47:46 drh Exp $
*/ */
#ifndef SQLITE_OMIT_DISKIO #ifndef SQLITE_OMIT_DISKIO
#include "sqliteInt.h" #include "sqliteInt.h"
@@ -490,7 +490,7 @@ static void checkPage(PgHdr *pPg){
#define pager_datahash(X,Y) 0 #define pager_datahash(X,Y) 0
#define pager_pagehash(X) 0 #define pager_pagehash(X) 0
#define CHECK_PAGE(x) #define CHECK_PAGE(x)
#endif #endif /* SQLITE_CHECK_PAGES */
/* /*
** When this is called the journal file for pager pPager must be open. ** When this is called the journal file for pager pPager must be open.
@@ -1868,7 +1868,8 @@ int sqlite3PagerOpen(
return ((rc==SQLITE_OK)?SQLITE_NOMEM:rc); return ((rc==SQLITE_OK)?SQLITE_NOMEM:rc);
} }
nExtra = FORCE_ALIGNMENT(nExtra); nExtra = FORCE_ALIGNMENT(nExtra);
sqlite3PcacheOpen(szPageDflt, nExtra, !memDb, xDesc, !memDb?pagerStress:0, (void *)pPager, pPager->pPCache); sqlite3PcacheOpen(szPageDflt, nExtra, !memDb, xDesc,
!memDb?pagerStress:0, (void *)pPager, pPager->pPCache);
PAGERTRACE3("OPEN %d %s\n", FILEHANDLEID(pPager->fd), pPager->zFilename); PAGERTRACE3("OPEN %d %s\n", FILEHANDLEID(pPager->fd), pPager->zFilename);
IOTRACE(("OPEN %p %s\n", pPager, pPager->zFilename)) IOTRACE(("OPEN %p %s\n", pPager, pPager->zFilename))

109
src/pcache.c
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@@ -11,7 +11,7 @@
************************************************************************* *************************************************************************
** This file implements that page cache. ** This file implements that page cache.
** **
** @(#) $Id: pcache.c,v 1.1 2008/08/20 14:49:25 danielk1977 Exp $ ** @(#) $Id: pcache.c,v 1.2 2008/08/20 21:47:46 drh Exp $
*/ */
#include "sqliteInt.h" #include "sqliteInt.h"
@@ -99,13 +99,13 @@ static struct PCacheGlobal {
** mutex released (in that order) before making the call. ** mutex released (in that order) before making the call.
*/ */
#define enterPcacheGlobal() sqlite3_mutex_enter(pcache.mutex_lru) #define pcacheEnterGlobal() sqlite3_mutex_enter(pcache.mutex_lru)
#define exitPcacheGlobal() sqlite3_mutex_leave(pcache.mutex_lru) #define pcacheExitGlobal() sqlite3_mutex_leave(pcache.mutex_lru)
/* /*
** Increment the reference count on both page p and its cache by n. ** Increment the reference count on both page p and its cache by n.
*/ */
static void page_ref(PgHdr *p, int n){ static void pcacheRef(PgHdr *p, int n){
/* This next block assert()s that the number of references to the /* This next block assert()s that the number of references to the
** PCache is the sum of the number of references to all pages in ** PCache is the sum of the number of references to all pages in
** the PCache. This is a bit expensive to leave turned on all the ** the PCache. This is a bit expensive to leave turned on all the
@@ -124,7 +124,13 @@ static void page_ref(PgHdr *p, int n){
/********************************** Linked List Management ********************/ /********************************** Linked List Management ********************/
static int check_hash_count(PCache *pCache){ #ifndef NDEBUG
/*
** This routine verifies that the number of entries in the hash table
** is pCache->nPage. This routine is used within assert() statements
** only and is therefore disabled during production builds.
*/
static int pcacheCheckHashCount(PCache *pCache){
int i; int i;
int nPage = 0; int nPage = 0;
for(i=0; i<pCache->nHash; i++){ for(i=0; i<pCache->nHash; i++){
@@ -136,6 +142,7 @@ static int check_hash_count(PCache *pCache){
assert( nPage==pCache->nPage ); assert( nPage==pCache->nPage );
return 1; return 1;
} }
#endif
/* /*
** Remove a page from its hash table (PCache.apHash[]). ** Remove a page from its hash table (PCache.apHash[]).
@@ -153,7 +160,7 @@ static void pcacheRemoveFromHash(PgHdr *pPage){
pPage->pNextHash->pPrevHash = pPage->pPrevHash; pPage->pNextHash->pPrevHash = pPage->pPrevHash;
} }
pPage->pCache->nPage--; pPage->pCache->nPage--;
assert( check_hash_count(pPage->pCache) ); assert( pcacheCheckHashCount(pPage->pCache) );
} }
/* /*
@@ -169,11 +176,12 @@ static void pcacheAddToHash(PgHdr *pPage){
} }
pCache->apHash[h] = pPage; pCache->apHash[h] = pPage;
pCache->nPage++; pCache->nPage++;
assert( check_hash_count(pCache) ); assert( pcacheCheckHashCount(pCache) );
} }
/* /*
** Resize the hash table to nHash buckets. ** Attempt to increase the size the hash table to contain
** at least nHash buckets.
*/ */
static int pcacheResizeHash(PCache *pCache, int nHash){ static int pcacheResizeHash(PCache *pCache, int nHash){
#ifdef SQLITE_MALLOC_SOFT_LIMIT #ifdef SQLITE_MALLOC_SOFT_LIMIT
@@ -333,9 +341,9 @@ void *pcacheMalloc(int sz){
} }
void *sqlite3PageMalloc(sz){ void *sqlite3PageMalloc(sz){
void *p; void *p;
enterPcacheGlobal(); pcacheEnterGlobal();
p = pcacheMalloc(sz); p = pcacheMalloc(sz);
exitPcacheGlobal(); pcacheExitGlobal();
return p; return p;
} }
@@ -358,9 +366,9 @@ void pcacheFree(void *p){
} }
} }
void sqlite3PageFree(void *p){ void sqlite3PageFree(void *p){
enterPcacheGlobal(); pcacheEnterGlobal();
pcacheFree(p); pcacheFree(p);
exitPcacheGlobal(); pcacheExitGlobal();
} }
/* /*
@@ -415,7 +423,7 @@ static PgHdr *pcacheRecycleOrAlloc(PCache *pCache){
assert( pcache.isInit ); assert( pcache.isInit );
assert( sqlite3_mutex_notheld(pcache.mutex_lru) ); assert( sqlite3_mutex_notheld(pcache.mutex_lru) );
enterPcacheGlobal(); pcacheEnterGlobal();
if( (pcache.mxPage && pcache.nPage>=pcache.mxPage) if( (pcache.mxPage && pcache.nPage>=pcache.mxPage)
|| (!pcache.mxPage && bPurg && pcache.nPurgeable>=pcache.mxPagePurgeable) || (!pcache.mxPage && bPurg && pcache.nPurgeable>=pcache.mxPagePurgeable)
@@ -435,9 +443,9 @@ static PgHdr *pcacheRecycleOrAlloc(PCache *pCache){
assert( pCsr->iInUseMM==0 ); assert( pCsr->iInUseMM==0 );
pCsr->iInUseMM = 1; pCsr->iInUseMM = 1;
if( pCsr->xStress && (pCsr->iInUseDB==0 || pCache==pCsr) ){ if( pCsr->xStress && (pCsr->iInUseDB==0 || pCache==pCsr) ){
exitPcacheGlobal(); pcacheExitGlobal();
pCsr->xStress(pCsr->pStress); pCsr->xStress(pCsr->pStress);
enterPcacheGlobal(); pcacheEnterGlobal();
} }
pCsr->iInUseMM = 0; pCsr->iInUseMM = 0;
} }
@@ -472,7 +480,7 @@ static PgHdr *pcacheRecycleOrAlloc(PCache *pCache){
p = pcachePageAlloc(szPage, szExtra, bPurg); p = pcachePageAlloc(szPage, szExtra, bPurg);
} }
exitPcacheGlobal(); pcacheExitGlobal();
return p; return p;
} }
@@ -527,9 +535,9 @@ void sqlite3PcacheOpen(
p->nMax = 100; p->nMax = 100;
if( bPurgeable ){ if( bPurgeable ){
enterPcacheGlobal(); pcacheEnterGlobal();
pcache.mxPagePurgeable += p->nMax; pcache.mxPagePurgeable += p->nMax;
exitPcacheGlobal(); pcacheExitGlobal();
} }
/* Add the new pager-cache to the list of caches starting at pcache.pAll */ /* Add the new pager-cache to the list of caches starting at pcache.pAll */
@@ -543,6 +551,10 @@ void sqlite3PcacheOpen(
sqlite3_mutex_leave(pcache.mutex_mem2); sqlite3_mutex_leave(pcache.mutex_mem2);
} }
/*
** Change the page size for PCache object. This can only happen
** when the cache is empty.
*/
void sqlite3PcacheSetPageSize(PCache *pCache, int szPage){ void sqlite3PcacheSetPageSize(PCache *pCache, int szPage){
assert(pCache->nPage==0); assert(pCache->nPage==0);
pCache->szPage = szPage; pCache->szPage = szPage;
@@ -569,11 +581,11 @@ int sqlite3PcacheFetch(
for(pPage=pCache->apHash[h]; pPage; pPage=pPage->pNextHash){ for(pPage=pCache->apHash[h]; pPage; pPage=pPage->pNextHash){
if( pPage->pgno==pgno ){ if( pPage->pgno==pgno ){
if( pPage->nRef==0 && (pPage->flags & PGHDR_DIRTY)==0 ){ if( pPage->nRef==0 && (pPage->flags & PGHDR_DIRTY)==0 ){
enterPcacheGlobal(); pcacheEnterGlobal();
pcacheRemoveFromLruList(pPage); pcacheRemoveFromLruList(pPage);
exitPcacheGlobal(); pcacheExitGlobal();
} }
page_ref(pPage, 1); pcacheRef(pPage, 1);
*ppPage = pPage; *ppPage = pPage;
return SQLITE_OK; return SQLITE_OK;
} }
@@ -600,7 +612,7 @@ int sqlite3PcacheFetch(
pPage->nRef = 0; pPage->nRef = 0;
pPage->pgno = pgno; pPage->pgno = pgno;
pPage->pCache = pCache; pPage->pCache = pCache;
page_ref(pPage, 1); pcacheRef(pPage, 1);
pcacheAddToList(&pCache->pClean, pPage); pcacheAddToList(&pCache->pClean, pPage);
pcacheAddToHash(pPage); pcacheAddToHash(pPage);
}else{ }else{
@@ -617,20 +629,20 @@ int sqlite3PcacheFetch(
void sqlite3PcacheRelease(PgHdr *p){ void sqlite3PcacheRelease(PgHdr *p){
assert( p->nRef>0 ); assert( p->nRef>0 );
assert( p->pCache->iInUseDB || p->pCache->iInUseMM ); assert( p->pCache->iInUseDB || p->pCache->iInUseMM );
page_ref(p, -1); pcacheRef(p, -1);
if( p->nRef!=0 ) return; if( p->nRef!=0 ) return;
if( p->pCache->xDestroy ){ if( p->pCache->xDestroy ){
p->pCache->xDestroy(p); p->pCache->xDestroy(p);
} }
if( (p->flags & PGHDR_DIRTY)!=0 ) return; if( (p->flags & PGHDR_DIRTY)!=0 ) return;
enterPcacheGlobal(); pcacheEnterGlobal();
pcacheAddToLruList(p); pcacheAddToLruList(p);
exitPcacheGlobal(); pcacheExitGlobal();
} }
void sqlite3PcacheRef(PgHdr *p){ void sqlite3PcacheRef(PgHdr *p){
assert(p->nRef>=0); assert(p->nRef>=0);
page_ref(p, 1); pcacheRef(p, 1);
} }
/* /*
@@ -649,9 +661,9 @@ void sqlite3PcacheDrop(PgHdr *p){
pcacheRemoveFromList(&pCache->pClean, p); pcacheRemoveFromList(&pCache->pClean, p);
} }
pcacheRemoveFromHash(p); pcacheRemoveFromHash(p);
enterPcacheGlobal(); pcacheEnterGlobal();
pcachePageFree(p); pcachePageFree(p);
exitPcacheGlobal(); pcacheExitGlobal();
} }
/* /*
@@ -686,9 +698,9 @@ void sqlite3PcacheMakeClean(PgHdr *p){
pcacheAddToList(&pCache->pClean, p); pcacheAddToList(&pCache->pClean, p);
p->flags &= ~PGHDR_DIRTY; p->flags &= ~PGHDR_DIRTY;
if( p->nRef==0 ){ if( p->nRef==0 ){
enterPcacheGlobal(); pcacheEnterGlobal();
pcacheAddToLruList(p); pcacheAddToLruList(p);
exitPcacheGlobal(); pcacheExitGlobal();
} }
} }
@@ -704,9 +716,9 @@ void sqlite3PcacheCleanAll(PCache *pCache){
pcacheAddToList(&pCache->pClean, p); pcacheAddToList(&pCache->pClean, p);
p->flags &= ~PGHDR_DIRTY; p->flags &= ~PGHDR_DIRTY;
if( p->nRef==0 ){ if( p->nRef==0 ){
enterPcacheGlobal(); pcacheEnterGlobal();
pcacheAddToLruList(p); pcacheAddToLruList(p);
exitPcacheGlobal(); pcacheExitGlobal();
} }
} }
} }
@@ -722,10 +734,10 @@ void sqlite3PcacheMove(PgHdr *p, Pgno newPgno){
p->pgno = newPgno; p->pgno = newPgno;
if( newPgno==0 ){ if( newPgno==0 ){
p->flags |= PGHDR_REUSE_UNLIKELY; p->flags |= PGHDR_REUSE_UNLIKELY;
enterPcacheGlobal(); pcacheEnterGlobal();
pcacheFree(p->apSave[0]); pcacheFree(p->apSave[0]);
pcacheFree(p->apSave[1]); pcacheFree(p->apSave[1]);
exitPcacheGlobal(); pcacheExitGlobal();
p->apSave[0] = 0; p->apSave[0] = 0;
p->apSave[1] = 0; p->apSave[1] = 0;
sqlite3PcacheMakeClean(p); sqlite3PcacheMakeClean(p);
@@ -737,9 +749,9 @@ void sqlite3PcacheMove(PgHdr *p, Pgno newPgno){
** Set the global maximum number of pages. Return the previous value. ** Set the global maximum number of pages. Return the previous value.
*/ */
void sqlite3PcacheGlobalMax(int mx){ void sqlite3PcacheGlobalMax(int mx){
enterPcacheGlobal(); pcacheEnterGlobal();
pcache.mxPage = mx; pcache.mxPage = mx;
exitPcacheGlobal(); pcacheExitGlobal();
} }
/* /*
@@ -771,7 +783,7 @@ void sqlite3PcacheTruncate(PCache *pCache, Pgno pgno){
PgHdr *p, *pNext; PgHdr *p, *pNext;
PgHdr *pDirty = pCache->pDirty; PgHdr *pDirty = pCache->pDirty;
assert( pCache->iInUseDB ); assert( pCache->iInUseDB );
enterPcacheGlobal(); pcacheEnterGlobal();
for(p=pCache->pClean; p||pDirty; p=pNext){ for(p=pCache->pClean; p||pDirty; p=pNext){
if( !p ){ if( !p ){
p = pDirty; p = pDirty;
@@ -796,7 +808,7 @@ void sqlite3PcacheTruncate(PCache *pCache, Pgno pgno){
} }
} }
} }
exitPcacheGlobal(); pcacheExitGlobal();
} }
@@ -809,13 +821,13 @@ void sqlite3PcacheClose(PCache *pCache){
/* Free all the pages used by this pager and remove them from the LRU /* Free all the pages used by this pager and remove them from the LRU
** list. This requires the protection of the MUTEX_STATIC_LRU mutex. ** list. This requires the protection of the MUTEX_STATIC_LRU mutex.
*/ */
enterPcacheGlobal(); pcacheEnterGlobal();
pcacheClear(pCache); pcacheClear(pCache);
if( pCache->bPurgeable ){ if( pCache->bPurgeable ){
pcache.mxPagePurgeable -= pCache->nMax; pcache.mxPagePurgeable -= pCache->nMax;
} }
sqlite3_free(pCache->apHash); sqlite3_free(pCache->apHash);
exitPcacheGlobal(); pcacheExitGlobal();
/* Now remove the pager-cache structure itself from the list of /* Now remove the pager-cache structure itself from the list of
** all such structures headed by pcache.pAll. This required the ** all such structures headed by pcache.pAll. This required the
@@ -865,14 +877,14 @@ int sqlite3PcachePreserve(PgHdr *p, int idJournal){
void sqlite3PcacheCommit(PCache *pCache, int idJournal){ void sqlite3PcacheCommit(PCache *pCache, int idJournal){
PgHdr *p; PgHdr *p;
assert( pCache->iInUseDB ); assert( pCache->iInUseDB );
enterPcacheGlobal(); /* Mutex is required to call pcacheFree() */ pcacheEnterGlobal(); /* Mutex is required to call pcacheFree() */
for(p=pCache->pDirty; p; p=p->pNext){ for(p=pCache->pDirty; p; p=p->pNext){
if( p->apSave[idJournal] ){ if( p->apSave[idJournal] ){
pcacheFree(p->apSave[idJournal]); pcacheFree(p->apSave[idJournal]);
p->apSave[idJournal] = 0; p->apSave[idJournal] = 0;
} }
} }
exitPcacheGlobal(); pcacheExitGlobal();
} }
/* /*
@@ -882,7 +894,7 @@ void sqlite3PcacheRollback(PCache *pCache, int idJournal){
PgHdr *p; PgHdr *p;
int sz; int sz;
assert( pCache->iInUseDB ); assert( pCache->iInUseDB );
enterPcacheGlobal(); /* Mutex is required to call pcacheFree() */ pcacheEnterGlobal(); /* Mutex is required to call pcacheFree() */
sz = pCache->szPage; sz = pCache->szPage;
for(p=pCache->pDirty; p; p=p->pNext){ for(p=pCache->pDirty; p; p=p->pNext){
if( p->apSave[idJournal] ){ if( p->apSave[idJournal] ){
@@ -891,7 +903,7 @@ void sqlite3PcacheRollback(PCache *pCache, int idJournal){
p->apSave[idJournal] = 0; p->apSave[idJournal] = 0;
} }
} }
exitPcacheGlobal(); pcacheExitGlobal();
} }
/* /*
@@ -916,9 +928,9 @@ void sqlite3PcacheAssertFlags(PCache *pCache, int trueMask, int falseMask){
int sqlite3PcacheClear(PCache *pCache){ int sqlite3PcacheClear(PCache *pCache){
assert( pCache->iInUseDB ); assert( pCache->iInUseDB );
assert(pCache->nRef==0); assert(pCache->nRef==0);
enterPcacheGlobal(); pcacheEnterGlobal();
pcacheClear(pCache); pcacheClear(pCache);
exitPcacheGlobal(); pcacheExitGlobal();
return SQLITE_OK; return SQLITE_OK;
} }
@@ -1100,10 +1112,10 @@ void sqlite3PcacheSetCachesize(PCache *pCache, int mxPage){
mxPage = 10; mxPage = 10;
} }
if( pCache->bPurgeable ){ if( pCache->bPurgeable ){
enterPcacheGlobal(); pcacheEnterGlobal();
pcache.mxPagePurgeable -= pCache->nMax; pcache.mxPagePurgeable -= pCache->nMax;
pcache.mxPagePurgeable += mxPage; pcache.mxPagePurgeable += mxPage;
exitPcacheGlobal(); pcacheExitGlobal();
} }
pCache->nMax = mxPage; pCache->nMax = mxPage;
} }
@@ -1129,4 +1141,3 @@ void sqlite3PcacheUnlock(PCache *pCache){
pCache->iInUseDB--; pCache->iInUseDB--;
assert( pCache->iInUseDB>=0 ); assert( pCache->iInUseDB>=0 );
} }