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This commit is contained in:
Hongze Cheng 2022-02-21 08:08:36 +00:00
parent f2096385d0
commit 7248dc6868
3 changed files with 378 additions and 382 deletions
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489
source/libs/tdb/src/sqlite/pcache.c
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@ -48,8 +48,8 @@ struct PCache {
int szExtra; /* Size of extra space for each page */
u8 bPurgeable; /* True if pages are on backing store */
u8 eCreate; /* eCreate value for for xFetch() */
int (*xStress)(void*,PgHdr*); /* Call to try make a page clean */
void *pStress; /* Argument to xStress */
int (*xStress)(void *, PgHdr *); /* Call to try make a page clean */
void * pStress; /* Argument to xStress */
sqlite3_pcache *pCache; /* Pluggable cache module */
};
@ -63,36 +63,39 @@ struct PCache {
** is displayed for many operations, resulting in a lot of output.
*/
#if defined(SQLITE_DEBUG) && 0
int sqlite3PcacheTrace = 2; /* 0: off 1: simple 2: cache dumps */
int sqlite3PcacheMxDump = 9999; /* Max cache entries for pcacheDump() */
# define pcacheTrace(X) if(sqlite3PcacheTrace){sqlite3DebugPrintf X;}
void pcacheDump(PCache *pCache){
int sqlite3PcacheTrace = 2; /* 0: off 1: simple 2: cache dumps */
int sqlite3PcacheMxDump = 9999; /* Max cache entries for pcacheDump() */
#define pcacheTrace(X) \
if (sqlite3PcacheTrace) { \
sqlite3DebugPrintf X; \
}
void pcacheDump(PCache *pCache) {
int N;
int i, j;
sqlite3_pcache_page *pLower;
PgHdr *pPg;
unsigned char *a;
PgHdr * pPg;
unsigned char * a;
if( sqlite3PcacheTrace<2 ) return;
if( pCache->pCache==0 ) return;
if (sqlite3PcacheTrace < 2) return;
if (pCache->pCache == 0) return;
N = sqlite3PcachePagecount(pCache);
if( N>sqlite3PcacheMxDump ) N = sqlite3PcacheMxDump;
for(i=1; i<=N; i++){
pLower = sqlite3GlobalConfig.pcache2.xFetch(pCache->pCache, i, 0);
if( pLower==0 ) continue;
pPg = (PgHdr*)pLower->pExtra;
if (N > sqlite3PcacheMxDump) N = sqlite3PcacheMxDump;
for (i = 1; i <= N; i++) {
pLower = pcache2.xFetch(pCache->pCache, i, 0);
if (pLower == 0) continue;
pPg = (PgHdr *)pLower->pExtra;
printf("%3d: nRef %2d flgs %02x data ", i, pPg->nRef, pPg->flags);
a = (unsigned char *)pLower->pBuf;
for(j=0; j<12; j++) printf("%02x", a[j]);
for (j = 0; j < 12; j++) printf("%02x", a[j]);
printf("\n");
if( pPg->pPage==0 ){
sqlite3GlobalConfig.pcache2.xUnpin(pCache->pCache, pLower, 0);
if (pPg->pPage == 0) {
pcache2.xUnpin(pCache->pCache, pLower, 0);
}
}
}
#else
# define pcacheTrace(X)
# define pcacheDump(X)
}
#else
#define pcacheTrace(X)
#define pcacheDump(X)
#endif
/*
@ -105,20 +108,20 @@ struct PCache {
** assert( sqlite3PcachePageSanity(pPg) );
*/
#ifdef SQLITE_DEBUG
int sqlite3PcachePageSanity(PgHdr *pPg){
int sqlite3PcachePageSanity(PgHdr *pPg) {
PCache *pCache;
assert( pPg!=0 );
assert( pPg->pgno>0 || pPg->pPager==0 ); /* Page number is 1 or more */
assert(pPg != 0);
assert(pPg->pgno > 0 || pPg->pPager == 0); /* Page number is 1 or more */
pCache = pPg->pCache;
assert( pCache!=0 ); /* Every page has an associated PCache */
if( pPg->flags & PGHDR_CLEAN ){
assert( (pPg->flags & PGHDR_DIRTY)==0 );/* Cannot be both CLEAN and DIRTY */
assert( pCache->pDirty!=pPg ); /* CLEAN pages not on dirty list */
assert( pCache->pDirtyTail!=pPg );
assert(pCache != 0); /* Every page has an associated PCache */
if (pPg->flags & PGHDR_CLEAN) {
assert((pPg->flags & PGHDR_DIRTY) == 0); /* Cannot be both CLEAN and DIRTY */
assert(pCache->pDirty != pPg); /* CLEAN pages not on dirty list */
assert(pCache->pDirtyTail != pPg);
}
/* WRITEABLE pages must also be DIRTY */
if( pPg->flags & PGHDR_WRITEABLE ){
assert( pPg->flags & PGHDR_DIRTY ); /* WRITEABLE implies DIRTY */
if (pPg->flags & PGHDR_WRITEABLE) {
assert(pPg->flags & PGHDR_DIRTY); /* WRITEABLE implies DIRTY */
}
/* NEED_SYNC can be set independently of WRITEABLE. This can happen,
** for example, when using the sqlite3PagerDontWrite() optimization:
@ -141,7 +144,6 @@ int sqlite3PcachePageSanity(PgHdr *pPg){
}
#endif /* SQLITE_DEBUG */
/********************************** Linked List Management ********************/
/* Allowed values for second argument to pcacheManageDirtyList() */
@ -155,53 +157,51 @@ int sqlite3PcachePageSanity(PgHdr *pPg){
** remove pPage from the dirty list. The 0x02 means add pPage back to
** the dirty list. Doing both moves pPage to the front of the dirty list.
*/
static void pcacheManageDirtyList(PgHdr *pPage, u8 addRemove){
static void pcacheManageDirtyList(PgHdr *pPage, u8 addRemove) {
PCache *p = pPage->pCache;
pcacheTrace(("%p.DIRTYLIST.%s %d\n", p,
addRemove==1 ? "REMOVE" : addRemove==2 ? "ADD" : "FRONT",
pPage->pgno));
if( addRemove & PCACHE_DIRTYLIST_REMOVE ){
assert( pPage->pDirtyNext || pPage==p->pDirtyTail );
assert( pPage->pDirtyPrev || pPage==p->pDirty );
pcacheTrace(("%p.DIRTYLIST.%s %d\n", p, addRemove == 1 ? "REMOVE" : addRemove == 2 ? "ADD" : "FRONT", pPage->pgno));
if (addRemove & PCACHE_DIRTYLIST_REMOVE) {
assert(pPage->pDirtyNext || pPage == p->pDirtyTail);
assert(pPage->pDirtyPrev || pPage == p->pDirty);
/* Update the PCache1.pSynced variable if necessary. */
if( p->pSynced==pPage ){
if (p->pSynced == pPage) {
p->pSynced = pPage->pDirtyPrev;
}
if( pPage->pDirtyNext ){
if (pPage->pDirtyNext) {
pPage->pDirtyNext->pDirtyPrev = pPage->pDirtyPrev;
}else{
assert( pPage==p->pDirtyTail );
} else {
assert(pPage == p->pDirtyTail);
p->pDirtyTail = pPage->pDirtyPrev;
}
if( pPage->pDirtyPrev ){
if (pPage->pDirtyPrev) {
pPage->pDirtyPrev->pDirtyNext = pPage->pDirtyNext;
}else{
} else {
/* If there are now no dirty pages in the cache, set eCreate to 2.
** This is an optimization that allows sqlite3PcacheFetch() to skip
** searching for a dirty page to eject from the cache when it might
** otherwise have to. */
assert( pPage==p->pDirty );
assert(pPage == p->pDirty);
p->pDirty = pPage->pDirtyNext;
assert( p->bPurgeable || p->eCreate==2 );
if( p->pDirty==0 ){ /*OPTIMIZATION-IF-TRUE*/
assert( p->bPurgeable==0 || p->eCreate==1 );
assert(p->bPurgeable || p->eCreate == 2);
if (p->pDirty == 0) { /*OPTIMIZATION-IF-TRUE*/
assert(p->bPurgeable == 0 || p->eCreate == 1);
p->eCreate = 2;
}
}
}
if( addRemove & PCACHE_DIRTYLIST_ADD ){
if (addRemove & PCACHE_DIRTYLIST_ADD) {
pPage->pDirtyPrev = 0;
pPage->pDirtyNext = p->pDirty;
if( pPage->pDirtyNext ){
assert( pPage->pDirtyNext->pDirtyPrev==0 );
if (pPage->pDirtyNext) {
assert(pPage->pDirtyNext->pDirtyPrev == 0);
pPage->pDirtyNext->pDirtyPrev = pPage;
}else{
} else {
p->pDirtyTail = pPage;
if( p->bPurgeable ){
assert( p->eCreate==2 );
if (p->bPurgeable) {
assert(p->eCreate == 2);
p->eCreate = 1;
}
}
@ -212,9 +212,8 @@ static void pcacheManageDirtyList(PgHdr *pPage, u8 addRemove){
** optimization, as if pSynced points to a page with the NEED_SYNC
** flag set sqlite3PcacheFetchStress() searches through all newer
** entries of the dirty-list for a page with NEED_SYNC clear anyway. */
if( !p->pSynced
&& 0==(pPage->flags&PGHDR_NEED_SYNC) /*OPTIMIZATION-IF-FALSE*/
){
if (!p->pSynced && 0 == (pPage->flags & PGHDR_NEED_SYNC) /*OPTIMIZATION-IF-FALSE*/
) {
p->pSynced = pPage;
}
}
@ -225,10 +224,10 @@ static void pcacheManageDirtyList(PgHdr *pPage, u8 addRemove){
** Wrapper around the pluggable caches xUnpin method. If the cache is
** being used for an in-memory database, this function is a no-op.
*/
static void pcacheUnpin(PgHdr *p){
if( p->pCache->bPurgeable ){
static void pcacheUnpin(PgHdr *p) {
if (p->pCache->bPurgeable) {
pcacheTrace(("%p.UNPIN %d\n", p->pCache, p->pgno));
sqlite3GlobalConfig.pcache2.xUnpin(p->pCache->pCache, p->pPage, 0);
pcache2.xUnpin(p->pCache->pCache, p->pPage, 0);
pcacheDump(p->pCache);
}
}
@ -237,19 +236,19 @@ static void pcacheUnpin(PgHdr *p){
** Compute the number of pages of cache requested. p->szCache is the
** cache size requested by the "PRAGMA cache_size" statement.
*/
static int numberOfCachePages(PCache *p){
if( p->szCache>=0 ){
static int numberOfCachePages(PCache *p) {
if (p->szCache >= 0) {
/* IMPLEMENTATION-OF: R-42059-47211 If the argument N is positive then the
** suggested cache size is set to N. */
return p->szCache;
}else{
} else {
i64 n;
/* IMPLEMANTATION-OF: R-59858-46238 If the argument N is negative, then the
** number of cache pages is adjusted to be a number of pages that would
** use approximately abs(N*1024) bytes of memory based on the current
** page size. */
n = ((-1024*(i64)p->szCache)/(p->szPage+p->szExtra));
if( n>1000000000 ) n = 1000000000;
n = ((-1024 * (i64)p->szCache) / (p->szPage + p->szExtra));
if (n > 1000000000) n = 1000000000;
return (int)n;
}
}
@ -259,27 +258,18 @@ static int numberOfCachePages(PCache *p){
** Initialize and shutdown the page cache subsystem. Neither of these
** functions are threadsafe.
*/
int sqlite3PcacheInitialize(void){
if( sqlite3GlobalConfig.pcache2.xInit==0 ){
/* IMPLEMENTATION-OF: R-26801-64137 If the xInit() method is NULL, then the
** built-in default page cache is used instead of the application defined
** page cache. */
sqlite3PCacheSetDefault();
assert( sqlite3GlobalConfig.pcache2.xInit!=0 );
}
return sqlite3GlobalConfig.pcache2.xInit(sqlite3GlobalConfig.pcache2.pArg);
}
void sqlite3PcacheShutdown(void){
if( sqlite3GlobalConfig.pcache2.xShutdown ){
int sqlite3PcacheInitialize(void) { return pcache2.xInit(pcache2.pArg); }
void sqlite3PcacheShutdown(void) {
if (pcache2.xShutdown) {
/* IMPLEMENTATION-OF: R-26000-56589 The xShutdown() method may be NULL. */
sqlite3GlobalConfig.pcache2.xShutdown(sqlite3GlobalConfig.pcache2.pArg);
pcache2.xShutdown(pcache2.pArg);
}
}
/*
** Return the size in bytes of a PCache object.
*/
int sqlite3PcacheSize(void){ return sizeof(PCache); }
int sqlite3PcacheSize(void) { return sizeof(PCache); }
/*
** Create a new PCache object. Storage space to hold the object
@ -293,25 +283,24 @@ int sqlite3PcacheSize(void){ return sizeof(PCache); }
** to this module, the extra space really ends up being the MemPage
** structure in the pager.
*/
int sqlite3PcacheOpen(
int szPage, /* Size of every page */
int sqlite3PcacheOpen(int szPage, /* Size of every page */
int szExtra, /* Extra space associated with each page */
int bPurgeable, /* True if pages are on backing store */
int (*xStress)(void*,PgHdr*),/* Call to try to make pages clean */
void *pStress, /* Argument to xStress */
int (*xStress)(void *, PgHdr *), /* Call to try to make pages clean */
void * pStress, /* Argument to xStress */
PCache *p /* Preallocated space for the PCache */
){
) {
memset(p, 0, sizeof(PCache));
p->szPage = 1;
p->szExtra = szExtra;
assert( szExtra>=8 ); /* First 8 bytes will be zeroed */
assert(szExtra >= 8); /* First 8 bytes will be zeroed */
p->bPurgeable = bPurgeable;
p->eCreate = 2;
p->xStress = xStress;
p->pStress = pStress;
p->szCache = 100;
p->szSpill = 1;
pcacheTrace(("%p.OPEN szPage %d bPurgeable %d\n",p,szPage,bPurgeable));
pcacheTrace(("%p.OPEN szPage %d bPurgeable %d\n", p, szPage, bPurgeable));
return sqlite3PcacheSetPageSize(p, szPage);
}
@ -319,22 +308,19 @@ int sqlite3PcacheOpen(
** Change the page size for PCache object. The caller must ensure that there
** are no outstanding page references when this function is called.
*/
int sqlite3PcacheSetPageSize(PCache *pCache, int szPage){
assert( pCache->nRefSum==0 && pCache->pDirty==0 );
if( pCache->szPage ){
int sqlite3PcacheSetPageSize(PCache *pCache, int szPage) {
assert(pCache->nRefSum == 0 && pCache->pDirty == 0);
if (pCache->szPage) {
sqlite3_pcache *pNew;
pNew = sqlite3GlobalConfig.pcache2.xCreate(
szPage, pCache->szExtra + ROUND8(sizeof(PgHdr)),
pCache->bPurgeable
);
if( pNew==0 ) return SQLITE_NOMEM_BKPT;
sqlite3GlobalConfig.pcache2.xCachesize(pNew, numberOfCachePages(pCache));
if( pCache->pCache ){
sqlite3GlobalConfig.pcache2.xDestroy(pCache->pCache);
pNew = pcache2.xCreate(szPage, pCache->szExtra + ROUND8(sizeof(PgHdr)), pCache->bPurgeable);
if (pNew == 0) return SQLITE_NOMEM_BKPT;
pcache2.xCachesize(pNew, numberOfCachePages(pCache));
if (pCache->pCache) {
pcache2.xDestroy(pCache->pCache);
}
pCache->pCache = pNew;
pCache->szPage = szPage;
pcacheTrace(("%p.PAGESIZE %d\n",pCache,szPage));
pcacheTrace(("%p.PAGESIZE %d\n", pCache, szPage));
}
return SQLITE_OK;
}
@ -363,18 +349,17 @@ int sqlite3PcacheSetPageSize(PCache *pCache, int szPage){
** the stack on entry and pop them back off on exit, which saves a
** lot of pushing and popping.
*/
sqlite3_pcache_page *sqlite3PcacheFetch(
PCache *pCache, /* Obtain the page from this cache */
sqlite3_pcache_page *sqlite3PcacheFetch(PCache *pCache, /* Obtain the page from this cache */
Pgno pgno, /* Page number to obtain */
int createFlag /* If true, create page if it does not exist already */
){
) {
int eCreate;
sqlite3_pcache_page *pRes;
assert( pCache!=0 );
assert( pCache->pCache!=0 );
assert( createFlag==3 || createFlag==0 );
assert( pCache->eCreate==((pCache->bPurgeable && pCache->pDirty) ? 1 : 2) );
assert(pCache != 0);
assert(pCache->pCache != 0);
assert(createFlag == 3 || createFlag == 0);
assert(pCache->eCreate == ((pCache->bPurgeable && pCache->pDirty) ? 1 : 2));
/* eCreate defines what to do if the page does not exist.
** 0 Do not allocate a new page. (createFlag==0)
@ -384,12 +369,11 @@ sqlite3_pcache_page *sqlite3PcacheFetch(
** (createFlag==1 AND !(bPurgeable AND pDirty)
*/
eCreate = createFlag & pCache->eCreate;
assert( eCreate==0 || eCreate==1 || eCreate==2 );
assert( createFlag==0 || pCache->eCreate==eCreate );
assert( createFlag==0 || eCreate==1+(!pCache->bPurgeable||!pCache->pDirty) );
pRes = sqlite3GlobalConfig.pcache2.xFetch(pCache->pCache, pgno, eCreate);
pcacheTrace(("%p.FETCH %d%s (result: %p)\n",pCache,pgno,
createFlag?" create":"",pRes));
assert(eCreate == 0 || eCreate == 1 || eCreate == 2);
assert(createFlag == 0 || pCache->eCreate == eCreate);
assert(createFlag == 0 || eCreate == 1 + (!pCache->bPurgeable || !pCache->pDirty));
pRes = pcache2.xFetch(pCache->pCache, pgno, eCreate);
pcacheTrace(("%p.FETCH %d%s (result: %p)\n", pCache, pgno, createFlag ? " create" : "", pRes));
return pRes;
}
@ -404,15 +388,14 @@ sqlite3_pcache_page *sqlite3PcacheFetch(
**
** This routine should be invoked only after sqlite3PcacheFetch() fails.
*/
int sqlite3PcacheFetchStress(
PCache *pCache, /* Obtain the page from this cache */
int sqlite3PcacheFetchStress(PCache * pCache, /* Obtain the page from this cache */
Pgno pgno, /* Page number to obtain */
sqlite3_pcache_page **ppPage /* Write result here */
){
) {
PgHdr *pPg;
if( pCache->eCreate==2 ) return 0;
if (pCache->eCreate == 2) return 0;
if( sqlite3PcachePagecount(pCache)>pCache->szSpill ){
if (sqlite3PcachePagecount(pCache) > pCache->szSpill) {
/* Find a dirty page to write-out and recycle. First try to find a
** page that does not require a journal-sync (one with PGHDR_NEED_SYNC
** cleared), but if that is not possible settle for any other
@ -422,33 +405,29 @@ int sqlite3PcacheFetchStress(
** flag is currently referenced, then the following may leave pSynced
** set incorrectly (pointing to other than the LRU page with NEED_SYNC
** cleared). This is Ok, as pSynced is just an optimization. */
for(pPg=pCache->pSynced;
pPg && (pPg->nRef || (pPg->flags&PGHDR_NEED_SYNC));
pPg=pPg->pDirtyPrev
);
for (pPg = pCache->pSynced; pPg && (pPg->nRef || (pPg->flags & PGHDR_NEED_SYNC)); pPg = pPg->pDirtyPrev)
;
pCache->pSynced = pPg;
if( !pPg ){
for(pPg=pCache->pDirtyTail; pPg && pPg->nRef; pPg=pPg->pDirtyPrev);
if (!pPg) {
for (pPg = pCache->pDirtyTail; pPg && pPg->nRef; pPg = pPg->pDirtyPrev)
;
}
if( pPg ){
if (pPg) {
int rc;
#ifdef SQLITE_LOG_CACHE_SPILL
sqlite3_log(SQLITE_FULL,
"spill page %d making room for %d - cache used: %d/%d",
pPg->pgno, pgno,
sqlite3GlobalConfig.pcache2.xPagecount(pCache->pCache),
numberOfCachePages(pCache));
sqlite3_log(SQLITE_FULL, "spill page %d making room for %d - cache used: %d/%d", pPg->pgno, pgno,
pcache2.xPagecount(pCache->pCache), numberOfCachePages(pCache));
#endif
pcacheTrace(("%p.SPILL %d\n",pCache,pPg->pgno));
pcacheTrace(("%p.SPILL %d\n", pCache, pPg->pgno));
rc = pCache->xStress(pCache->pStress, pPg);
pcacheDump(pCache);
if( rc!=SQLITE_OK && rc!=SQLITE_BUSY ){
if (rc != SQLITE_OK && rc != SQLITE_BUSY) {
return rc;
}
}
}
*ppPage = sqlite3GlobalConfig.pcache2.xFetch(pCache->pCache, pgno, 2);
return *ppPage==0 ? SQLITE_NOMEM_BKPT : SQLITE_OK;
*ppPage = pcache2.xFetch(pCache->pCache, pgno, 2);
return *ppPage == 0 ? SQLITE_NOMEM_BKPT : SQLITE_OK;
}
/*
@ -461,15 +440,15 @@ int sqlite3PcacheFetchStress(
** case.
*/
static SQLITE_NOINLINE PgHdr *pcacheFetchFinishWithInit(
PCache *pCache, /* Obtain the page from this cache */
PCache * pCache, /* Obtain the page from this cache */
Pgno pgno, /* Page number obtained */
sqlite3_pcache_page *pPage /* Page obtained by prior PcacheFetch() call */
){
) {
PgHdr *pPgHdr;
assert( pPage!=0 );
pPgHdr = (PgHdr*)pPage->pExtra;
assert( pPgHdr->pPage==0 );
memset(&pPgHdr->pDirty, 0, sizeof(PgHdr) - offsetof(PgHdr,pDirty));
assert(pPage != 0);
pPgHdr = (PgHdr *)pPage->pExtra;
assert(pPgHdr->pPage == 0);
memset(&pPgHdr->pDirty, 0, sizeof(PgHdr) - offsetof(PgHdr, pDirty));
pPgHdr->pPage = pPage;
pPgHdr->pData = pPage->pBuf;
pPgHdr->pExtra = (void *)&pPgHdr[1];
@ -477,7 +456,7 @@ static SQLITE_NOINLINE PgHdr *pcacheFetchFinishWithInit(
pPgHdr->pCache = pCache;
pPgHdr->pgno = pgno;
pPgHdr->flags = PGHDR_CLEAN;
return sqlite3PcacheFetchFinish(pCache,pgno,pPage);
return sqlite3PcacheFetchFinish(pCache, pgno, pPage);
}
/*
@ -486,22 +465,21 @@ static SQLITE_NOINLINE PgHdr *pcacheFetchFinishWithInit(
** must be called after sqlite3PcacheFetch() in order to get a usable
** result.
*/
PgHdr *sqlite3PcacheFetchFinish(
PCache *pCache, /* Obtain the page from this cache */
PgHdr *sqlite3PcacheFetchFinish(PCache * pCache, /* Obtain the page from this cache */
Pgno pgno, /* Page number obtained */
sqlite3_pcache_page *pPage /* Page obtained by prior PcacheFetch() call */
){
) {
PgHdr *pPgHdr;
assert( pPage!=0 );
assert(pPage != 0);
pPgHdr = (PgHdr *)pPage->pExtra;
if( !pPgHdr->pPage ){
if (!pPgHdr->pPage) {
return pcacheFetchFinishWithInit(pCache, pgno, pPage);
}
pCache->nRefSum++;
pPgHdr->nRef++;
assert( sqlite3PcachePageSanity(pPgHdr) );
assert(sqlite3PcachePageSanity(pPgHdr));
return pPgHdr;
}
@ -509,13 +487,13 @@ PgHdr *sqlite3PcacheFetchFinish(
** Decrement the reference count on a page. If the page is clean and the
** reference count drops to 0, then it is made eligible for recycling.
*/
void SQLITE_NOINLINE sqlite3PcacheRelease(PgHdr *p){
assert( p->nRef>0 );
void SQLITE_NOINLINE sqlite3PcacheRelease(PgHdr *p) {
assert(p->nRef > 0);
p->pCache->nRefSum--;
if( (--p->nRef)==0 ){
if( p->flags&PGHDR_CLEAN ){
if ((--p->nRef) == 0) {
if (p->flags & PGHDR_CLEAN) {
pcacheUnpin(p);
}else{
} else {
pcacheManageDirtyList(p, PCACHE_DIRTYLIST_FRONT);
}
}
@ -524,9 +502,9 @@ void SQLITE_NOINLINE sqlite3PcacheRelease(PgHdr *p){
/*
** Increase the reference count of a supplied page by 1.
*/
void sqlite3PcacheRef(PgHdr *p){
assert(p->nRef>0);
assert( sqlite3PcachePageSanity(p) );
void sqlite3PcacheRef(PgHdr *p) {
assert(p->nRef > 0);
assert(sqlite3PcachePageSanity(p));
p->nRef++;
p->pCache->nRefSum++;
}
@ -536,32 +514,32 @@ void sqlite3PcacheRef(PgHdr *p){
** page. This function deletes that reference, so after it returns the
** page pointed to by p is invalid.
*/
void sqlite3PcacheDrop(PgHdr *p){
assert( p->nRef==1 );
assert( sqlite3PcachePageSanity(p) );
if( p->flags&PGHDR_DIRTY ){
void sqlite3PcacheDrop(PgHdr *p) {
assert(p->nRef == 1);
assert(sqlite3PcachePageSanity(p));
if (p->flags & PGHDR_DIRTY) {
pcacheManageDirtyList(p, PCACHE_DIRTYLIST_REMOVE);
}
p->pCache->nRefSum--;
sqlite3GlobalConfig.pcache2.xUnpin(p->pCache->pCache, p->pPage, 1);
pcache2.xUnpin(p->pCache->pCache, p->pPage, 1);
}
/*
** Make sure the page is marked as dirty. If it isn't dirty already,
** make it so.
*/
void sqlite3PcacheMakeDirty(PgHdr *p){
assert( p->nRef>0 );
assert( sqlite3PcachePageSanity(p) );
if( p->flags & (PGHDR_CLEAN|PGHDR_DONT_WRITE) ){ /*OPTIMIZATION-IF-FALSE*/
void sqlite3PcacheMakeDirty(PgHdr *p) {
assert(p->nRef > 0);
assert(sqlite3PcachePageSanity(p));
if (p->flags & (PGHDR_CLEAN | PGHDR_DONT_WRITE)) { /*OPTIMIZATION-IF-FALSE*/
p->flags &= ~PGHDR_DONT_WRITE;
if( p->flags & PGHDR_CLEAN ){
p->flags ^= (PGHDR_DIRTY|PGHDR_CLEAN);
pcacheTrace(("%p.DIRTY %d\n",p->pCache,p->pgno));
assert( (p->flags & (PGHDR_DIRTY|PGHDR_CLEAN))==PGHDR_DIRTY );
if (p->flags & PGHDR_CLEAN) {
p->flags ^= (PGHDR_DIRTY | PGHDR_CLEAN);
pcacheTrace(("%p.DIRTY %d\n", p->pCache, p->pgno));
assert((p->flags & (PGHDR_DIRTY | PGHDR_CLEAN)) == PGHDR_DIRTY);
pcacheManageDirtyList(p, PCACHE_DIRTYLIST_ADD);
}
assert( sqlite3PcachePageSanity(p) );
assert(sqlite3PcachePageSanity(p));
}
}
@ -569,16 +547,16 @@ void sqlite3PcacheMakeDirty(PgHdr *p){
** Make sure the page is marked as clean. If it isn't clean already,
** make it so.
*/
void sqlite3PcacheMakeClean(PgHdr *p){
assert( sqlite3PcachePageSanity(p) );
assert( (p->flags & PGHDR_DIRTY)!=0 );
assert( (p->flags & PGHDR_CLEAN)==0 );
void sqlite3PcacheMakeClean(PgHdr *p) {
assert(sqlite3PcachePageSanity(p));
assert((p->flags & PGHDR_DIRTY) != 0);
assert((p->flags & PGHDR_CLEAN) == 0);
pcacheManageDirtyList(p, PCACHE_DIRTYLIST_REMOVE);
p->flags &= ~(PGHDR_DIRTY|PGHDR_NEED_SYNC|PGHDR_WRITEABLE);
p->flags &= ~(PGHDR_DIRTY | PGHDR_NEED_SYNC | PGHDR_WRITEABLE);
p->flags |= PGHDR_CLEAN;
pcacheTrace(("%p.CLEAN %d\n",p->pCache,p->pgno));
assert( sqlite3PcachePageSanity(p) );
if( p->nRef==0 ){
pcacheTrace(("%p.CLEAN %d\n", p->pCache, p->pgno));
assert(sqlite3PcachePageSanity(p));
if (p->nRef == 0) {
pcacheUnpin(p);
}
}
@ -586,10 +564,10 @@ void sqlite3PcacheMakeClean(PgHdr *p){
/*
** Make every page in the cache clean.
*/
void sqlite3PcacheCleanAll(PCache *pCache){
void sqlite3PcacheCleanAll(PCache *pCache) {
PgHdr *p;
pcacheTrace(("%p.CLEAN-ALL\n",pCache));
while( (p = pCache->pDirty)!=0 ){
pcacheTrace(("%p.CLEAN-ALL\n", pCache));
while ((p = pCache->pDirty) != 0) {
sqlite3PcacheMakeClean(p);
}
}
@ -597,11 +575,11 @@ void sqlite3PcacheCleanAll(PCache *pCache){
/*
** Clear the PGHDR_NEED_SYNC and PGHDR_WRITEABLE flag from all dirty pages.
*/
void sqlite3PcacheClearWritable(PCache *pCache){
void sqlite3PcacheClearWritable(PCache *pCache) {
PgHdr *p;
pcacheTrace(("%p.CLEAR-WRITEABLE\n",pCache));
for(p=pCache->pDirty; p; p=p->pDirtyNext){
p->flags &= ~(PGHDR_NEED_SYNC|PGHDR_WRITEABLE);
pcacheTrace(("%p.CLEAR-WRITEABLE\n", pCache));
for (p = pCache->pDirty; p; p = p->pDirtyNext) {
p->flags &= ~(PGHDR_NEED_SYNC | PGHDR_WRITEABLE);
}
pCache->pSynced = pCache->pDirtyTail;
}
@ -609,9 +587,9 @@ void sqlite3PcacheClearWritable(PCache *pCache){
/*
** Clear the PGHDR_NEED_SYNC flag from all dirty pages.
*/
void sqlite3PcacheClearSyncFlags(PCache *pCache){
void sqlite3PcacheClearSyncFlags(PCache *pCache) {
PgHdr *p;
for(p=pCache->pDirty; p; p=p->pDirtyNext){
for (p = pCache->pDirty; p; p = p->pDirtyNext) {
p->flags &= ~PGHDR_NEED_SYNC;
}
pCache->pSynced = pCache->pDirtyTail;
@ -620,15 +598,15 @@ void sqlite3PcacheClearSyncFlags(PCache *pCache){
/*
** Change the page number of page p to newPgno.
*/
void sqlite3PcacheMove(PgHdr *p, Pgno newPgno){
void sqlite3PcacheMove(PgHdr *p, Pgno newPgno) {
PCache *pCache = p->pCache;
assert( p->nRef>0 );
assert( newPgno>0 );
assert( sqlite3PcachePageSanity(p) );
pcacheTrace(("%p.MOVE %d -> %d\n",pCache,p->pgno,newPgno));
sqlite3GlobalConfig.pcache2.xRekey(pCache->pCache, p->pPage, p->pgno,newPgno);
assert(p->nRef > 0);
assert(newPgno > 0);
assert(sqlite3PcachePageSanity(p));
pcacheTrace(("%p.MOVE %d -> %d\n", pCache, p->pgno, newPgno));
pcache2.xRekey(pCache->pCache, p->pPage, p->pgno, newPgno);
p->pgno = newPgno;
if( (p->flags&PGHDR_DIRTY) && (p->flags&PGHDR_NEED_SYNC) ){
if ((p->flags & PGHDR_DIRTY) && (p->flags & PGHDR_NEED_SYNC)) {
pcacheManageDirtyList(p, PCACHE_DIRTYLIST_FRONT);
}
}
@ -642,74 +620,72 @@ void sqlite3PcacheMove(PgHdr *p, Pgno newPgno){
** function is 0, then the data area associated with page 1 is zeroed, but
** the page object is not dropped.
*/
void sqlite3PcacheTruncate(PCache *pCache, Pgno pgno){
if( pCache->pCache ){
void sqlite3PcacheTruncate(PCache *pCache, Pgno pgno) {
if (pCache->pCache) {
PgHdr *p;
PgHdr *pNext;
pcacheTrace(("%p.TRUNCATE %d\n",pCache,pgno));
for(p=pCache->pDirty; p; p=pNext){
pcacheTrace(("%p.TRUNCATE %d\n", pCache, pgno));
for (p = pCache->pDirty; p; p = pNext) {
pNext = p->pDirtyNext;
/* This routine never gets call with a positive pgno except right
** after sqlite3PcacheCleanAll(). So if there are dirty pages,
** it must be that pgno==0.
*/
assert( p->pgno>0 );
if( p->pgno>pgno ){
assert( p->flags&PGHDR_DIRTY );
assert(p->pgno > 0);
if (p->pgno > pgno) {
assert(p->flags & PGHDR_DIRTY);
sqlite3PcacheMakeClean(p);
}
}
if( pgno==0 && pCache->nRefSum ){
if (pgno == 0 && pCache->nRefSum) {
sqlite3_pcache_page *pPage1;
pPage1 = sqlite3GlobalConfig.pcache2.xFetch(pCache->pCache,1,0);
if( ALWAYS(pPage1) ){ /* Page 1 is always available in cache, because
pPage1 = pcache2.xFetch(pCache->pCache, 1, 0);
if (ALWAYS(pPage1)) { /* Page 1 is always available in cache, because
** pCache->nRefSum>0 */
memset(pPage1->pBuf, 0, pCache->szPage);
pgno = 1;
}
}
sqlite3GlobalConfig.pcache2.xTruncate(pCache->pCache, pgno+1);
pcache2.xTruncate(pCache->pCache, pgno + 1);
}
}
/*
** Close a cache.
*/
void sqlite3PcacheClose(PCache *pCache){
assert( pCache->pCache!=0 );
pcacheTrace(("%p.CLOSE\n",pCache));
sqlite3GlobalConfig.pcache2.xDestroy(pCache->pCache);
void sqlite3PcacheClose(PCache *pCache) {
assert(pCache->pCache != 0);
pcacheTrace(("%p.CLOSE\n", pCache));
pcache2.xDestroy(pCache->pCache);
}
/*
** Discard the contents of the cache.
*/
void sqlite3PcacheClear(PCache *pCache){
sqlite3PcacheTruncate(pCache, 0);
}
void sqlite3PcacheClear(PCache *pCache) { sqlite3PcacheTruncate(pCache, 0); }
/*
** Merge two lists of pages connected by pDirty and in pgno order.
** Do not bother fixing the pDirtyPrev pointers.
*/
static PgHdr *pcacheMergeDirtyList(PgHdr *pA, PgHdr *pB){
static PgHdr *pcacheMergeDirtyList(PgHdr *pA, PgHdr *pB) {
PgHdr result, *pTail;
pTail = &result;
assert( pA!=0 && pB!=0 );
for(;;){
if( pA->pgno<pB->pgno ){
assert(pA != 0 && pB != 0);
for (;;) {
if (pA->pgno < pB->pgno) {
pTail->pDirty = pA;
pTail = pA;
pA = pA->pDirty;
if( pA==0 ){
if (pA == 0) {
pTail->pDirty = pB;
break;
}
}else{
} else {
pTail->pDirty = pB;
pTail = pB;
pB = pB->pDirty;
if( pB==0 ){
if (pB == 0) {
pTail->pDirty = pA;
break;
}
@ -729,24 +705,24 @@ static PgHdr *pcacheMergeDirtyList(PgHdr *pA, PgHdr *pB){
** ever changes to make the previous sentence incorrect.
*/
#define N_SORT_BUCKET 32
static PgHdr *pcacheSortDirtyList(PgHdr *pIn){
static PgHdr *pcacheSortDirtyList(PgHdr *pIn) {
PgHdr *a[N_SORT_BUCKET], *p;
int i;
memset(a, 0, sizeof(a));
while( pIn ){
while (pIn) {
p = pIn;
pIn = p->pDirty;
p->pDirty = 0;
for(i=0; ALWAYS(i<N_SORT_BUCKET-1); i++){
if( a[i]==0 ){
for (i = 0; ALWAYS(i < N_SORT_BUCKET - 1); i++) {
if (a[i] == 0) {
a[i] = p;
break;
}else{
} else {
p = pcacheMergeDirtyList(a[i], p);
a[i] = 0;
}
}
if( NEVER(i==N_SORT_BUCKET-1) ){
if (NEVER(i == N_SORT_BUCKET - 1)) {
/* To get here, there need to be 2^(N_SORT_BUCKET) elements in
** the input list. But that is impossible.
*/
@ -754,8 +730,8 @@ static PgHdr *pcacheSortDirtyList(PgHdr *pIn){
}
}
p = a[0];
for(i=1; i<N_SORT_BUCKET; i++){
if( a[i]==0 ) continue;
for (i = 1; i < N_SORT_BUCKET; i++) {
if (a[i] == 0) continue;
p = p ? pcacheMergeDirtyList(p, a[i]) : a[i];
}
return p;
@ -764,9 +740,9 @@ static PgHdr *pcacheSortDirtyList(PgHdr *pIn){
/*
** Return a list of all dirty pages in the cache, sorted by page number.
*/
PgHdr *sqlite3PcacheDirtyList(PCache *pCache){
PgHdr *sqlite3PcacheDirtyList(PCache *pCache) {
PgHdr *p;
for(p=pCache->pDirty; p; p=p->pDirtyNext){
for (p = pCache->pDirty; p; p = p->pDirtyNext) {
p->pDirty = p->pDirtyNext;
}
return pcacheSortDirtyList(pCache->pDirty);
@ -778,42 +754,35 @@ PgHdr *sqlite3PcacheDirtyList(PCache *pCache){
** This is not the total number of pages referenced, but the sum of the
** reference count for all pages.
*/
int sqlite3PcacheRefCount(PCache *pCache){
return pCache->nRefSum;
}
int sqlite3PcacheRefCount(PCache *pCache) { return pCache->nRefSum; }
/*
** Return the number of references to the page supplied as an argument.
*/
int sqlite3PcachePageRefcount(PgHdr *p){
return p->nRef;
}
int sqlite3PcachePageRefcount(PgHdr *p) { return p->nRef; }
/*
** Return the total number of pages in the cache.
*/
int sqlite3PcachePagecount(PCache *pCache){
assert( pCache->pCache!=0 );
return sqlite3GlobalConfig.pcache2.xPagecount(pCache->pCache);
int sqlite3PcachePagecount(PCache *pCache) {
assert(pCache->pCache != 0);
return pcache2.xPagecount(pCache->pCache);
}
#ifdef SQLITE_TEST
/*
** Get the suggested cache-size value.
*/
int sqlite3PcacheGetCachesize(PCache *pCache){
return numberOfCachePages(pCache);
}
int sqlite3PcacheGetCachesize(PCache *pCache) { return numberOfCachePages(pCache); }
#endif
/*
** Set the suggested cache-size value.
*/
void sqlite3PcacheSetCachesize(PCache *pCache, int mxPage){
assert( pCache->pCache!=0 );
void sqlite3PcacheSetCachesize(PCache *pCache, int mxPage) {
assert(pCache->pCache != 0);
pCache->szCache = mxPage;
sqlite3GlobalConfig.pcache2.xCachesize(pCache->pCache,
numberOfCachePages(pCache));
pcache2.xCachesize(pCache->pCache, numberOfCachePages(pCache));
}
/*
@ -821,43 +790,43 @@ void sqlite3PcacheSetCachesize(PCache *pCache, int mxPage){
** argument is zero. Return the effective cache-spill size, which will
** be the larger of the szSpill and szCache.
*/
int sqlite3PcacheSetSpillsize(PCache *p, int mxPage){
int sqlite3PcacheSetSpillsize(PCache *p, int mxPage) {
int res;
assert( p->pCache!=0 );
if( mxPage ){
if( mxPage<0 ){
mxPage = (int)((-1024*(i64)mxPage)/(p->szPage+p->szExtra));
assert(p->pCache != 0);
if (mxPage) {
if (mxPage < 0) {
mxPage = (int)((-1024 * (i64)mxPage) / (p->szPage + p->szExtra));
}
p->szSpill = mxPage;
}
res = numberOfCachePages(p);
if( res<p->szSpill ) res = p->szSpill;
if (res < p->szSpill) res = p->szSpill;
return res;
}
/*
** Free up as much memory as possible from the page cache.
*/
void sqlite3PcacheShrink(PCache *pCache){
assert( pCache->pCache!=0 );
sqlite3GlobalConfig.pcache2.xShrink(pCache->pCache);
void sqlite3PcacheShrink(PCache *pCache) {
assert(pCache->pCache != 0);
pcache2.xShrink(pCache->pCache);
}
/*
** Return the size of the header added by this middleware layer
** in the page-cache hierarchy.
*/
int sqlite3HeaderSizePcache(void){ return ROUND8(sizeof(PgHdr)); }
int sqlite3HeaderSizePcache(void) { return ROUND8(sizeof(PgHdr)); }
/*
** Return the number of dirty pages currently in the cache, as a percentage
** of the configured cache size.
*/
int sqlite3PCachePercentDirty(PCache *pCache){
int sqlite3PCachePercentDirty(PCache *pCache) {
PgHdr *pDirty;
int nDirty = 0;
int nCache = numberOfCachePages(pCache);
for(pDirty=pCache->pDirty; pDirty; pDirty=pDirty->pDirtyNext) nDirty++;
for (pDirty = pCache->pDirty; pDirty; pDirty = pDirty->pDirtyNext) nDirty++;
return nCache ? (int)(((i64)nDirty * 100) / nCache) : 0;
}
@ -865,9 +834,7 @@ int sqlite3PCachePercentDirty(PCache *pCache){
/*
** Return true if there are one or more dirty pages in the cache. Else false.
*/
int sqlite3PCacheIsDirty(PCache *pCache){
return (pCache->pDirty!=0);
}
int sqlite3PCacheIsDirty(PCache *pCache) { return (pCache->pDirty != 0); }
#endif
#if defined(SQLITE_CHECK_PAGES) || defined(SQLITE_DEBUG)
@ -876,9 +843,9 @@ int sqlite3PCacheIsDirty(PCache *pCache){
** callback. This is only used if the SQLITE_CHECK_PAGES macro is
** defined.
*/
void sqlite3PcacheIterateDirty(PCache *pCache, void (*xIter)(PgHdr *)){
void sqlite3PcacheIterateDirty(PCache *pCache, void (*xIter)(PgHdr *)) {
PgHdr *pDirty;
for(pDirty=pCache->pDirty; pDirty; pDirty=pDirty->pDirtyNext){
for (pDirty = pCache->pDirty; pDirty; pDirty = pDirty->pDirtyNext) {
xIter(pDirty);
}
}

27
source/libs/tdb/src/sqlite/pcache1.c
View File

@ -199,10 +199,26 @@ struct PgFreeslot {
PgFreeslot *pNext; /* Next free slot */
};
sqlite3_pcache_methods2 pcache2 = {
1, /* iVersion */
0, /* pArg */
pcache1Init, /* xInit */
pcache1Shutdown, /* xShutdown */
pcache1Create, /* xCreate */
pcache1Cachesize, /* xCachesize */
pcache1Pagecount, /* xPagecount */
pcache1Fetch, /* xFetch */
pcache1Unpin, /* xUnpin */
pcache1Rekey, /* xRekey */
pcache1Truncate, /* xTruncate */
pcache1Destroy, /* xDestroy */
pcache1Shrink /* xShrink */
};
/*
** Global data used by this cache.
*/
static SQLITE_WSD struct PCacheGlobal {
static struct PCacheGlobal {
PGroup grp; /* The global PGroup for mode (2) */
/* Variables related to SQLITE_CONFIG_PAGECACHE settings. The
@ -226,14 +242,7 @@ static SQLITE_WSD struct PCacheGlobal {
** (2) even if an incorrect value is read, no great harm is done since this
** is really just an optimization. */
int bUnderPressure; /* True if low on PAGECACHE memory */
} pcache1_g;
/*
** All code in this file should access the global structure above via the
** alias "pcache1". This ensures that the WSD emulation is used when
** compiling for systems that do not support real WSD.
*/
#define pcache1 (GLOBAL(struct PCacheGlobal, pcache1_g))
} pcache1;
/*
** Macros to enter and leave the PCache LRU mutex.

84
source/libs/tdb/src/sqliteinc/pcache.h
View File

@ -24,11 +24,11 @@ typedef struct PCache PCache;
*/
struct PgHdr {
sqlite3_pcache_page *pPage; /* Pcache object page handle */
void *pData; /* Page data */
void *pExtra; /* Extra content */
PCache *pCache; /* PRIVATE: Cache that owns this page */
PgHdr *pDirty; /* Transient list of dirty sorted by pgno */
Pager *pPager; /* The pager this page is part of */
void * pData; /* Page data */
void * pExtra; /* Extra content */
PCache * pCache; /* PRIVATE: Cache that owns this page */
PgHdr * pDirty; /* Transient list of dirty sorted by pgno */
Pager * pPager; /* The pager this page is part of */
Pgno pgno; /* Page number for this page */
#ifdef SQLITE_CHECK_PAGES
u32 pageHash; /* Hash of page content */
@ -51,7 +51,8 @@ struct PgHdr {
#define PGHDR_CLEAN 0x001 /* Page not on the PCache.pDirty list */
#define PGHDR_DIRTY 0x002 /* Page is on the PCache.pDirty list */
#define PGHDR_WRITEABLE 0x004 /* Journaled and ready to modify */
#define PGHDR_NEED_SYNC 0x008 /* Fsync the rollback journal before
#define PGHDR_NEED_SYNC \
0x008 /* Fsync the rollback journal before \
** writing this page to the database */
#define PGHDR_DONT_WRITE 0x010 /* Do not write content to disk */
#define PGHDR_MMAP 0x020 /* This is an mmap page object */
@ -71,12 +72,11 @@ void sqlite3PCacheBufferSetup(void *, int sz, int n);
** Under memory stress, invoke xStress to try to make pages clean.
** Only clean and unpinned pages can be reclaimed.
*/
int sqlite3PcacheOpen(
int szPage, /* Size of every page */
int sqlite3PcacheOpen(int szPage, /* Size of every page */
int szExtra, /* Extra space associated with each page */
int bPurgeable, /* True if pages are on backing store */
int (*xStress)(void*, PgHdr*), /* Call to try to make pages clean */
void *pStress, /* Argument to xStress */
int (*xStress)(void *, PgHdr *), /* Call to try to make pages clean */
void * pStress, /* Argument to xStress */
PCache *pToInit /* Preallocated space for the PCache */
);
@ -91,45 +91,45 @@ int sqlite3PcacheSize(void);
/* One release per successful fetch. Page is pinned until released.
** Reference counted.
*/
sqlite3_pcache_page *sqlite3PcacheFetch(PCache*, Pgno, int createFlag);
int sqlite3PcacheFetchStress(PCache*, Pgno, sqlite3_pcache_page**);
PgHdr *sqlite3PcacheFetchFinish(PCache*, Pgno, sqlite3_pcache_page *pPage);
void sqlite3PcacheRelease(PgHdr*);
sqlite3_pcache_page *sqlite3PcacheFetch(PCache *, Pgno, int createFlag);
int sqlite3PcacheFetchStress(PCache *, Pgno, sqlite3_pcache_page **);
PgHdr * sqlite3PcacheFetchFinish(PCache *, Pgno, sqlite3_pcache_page *pPage);
void sqlite3PcacheRelease(PgHdr *);
void sqlite3PcacheDrop(PgHdr*); /* Remove page from cache */
void sqlite3PcacheMakeDirty(PgHdr*); /* Make sure page is marked dirty */
void sqlite3PcacheMakeClean(PgHdr*); /* Mark a single page as clean */
void sqlite3PcacheCleanAll(PCache*); /* Mark all dirty list pages as clean */
void sqlite3PcacheClearWritable(PCache*);
void sqlite3PcacheDrop(PgHdr *); /* Remove page from cache */
void sqlite3PcacheMakeDirty(PgHdr *); /* Make sure page is marked dirty */
void sqlite3PcacheMakeClean(PgHdr *); /* Mark a single page as clean */
void sqlite3PcacheCleanAll(PCache *); /* Mark all dirty list pages as clean */
void sqlite3PcacheClearWritable(PCache *);
/* Change a page number. Used by incr-vacuum. */
void sqlite3PcacheMove(PgHdr*, Pgno);
void sqlite3PcacheMove(PgHdr *, Pgno);
/* Remove all pages with pgno>x. Reset the cache if x==0 */
void sqlite3PcacheTruncate(PCache*, Pgno x);
void sqlite3PcacheTruncate(PCache *, Pgno x);
/* Get a list of all dirty pages in the cache, sorted by page number */
PgHdr *sqlite3PcacheDirtyList(PCache*);
PgHdr *sqlite3PcacheDirtyList(PCache *);
/* Reset and close the cache object */
void sqlite3PcacheClose(PCache*);
void sqlite3PcacheClose(PCache *);
/* Clear flags from pages of the page cache */
void sqlite3PcacheClearSyncFlags(PCache *);
/* Discard the contents of the cache */
void sqlite3PcacheClear(PCache*);
void sqlite3PcacheClear(PCache *);
/* Return the total number of outstanding page references */
int sqlite3PcacheRefCount(PCache*);
int sqlite3PcacheRefCount(PCache *);
/* Increment the reference count of an existing page */
void sqlite3PcacheRef(PgHdr*);
void sqlite3PcacheRef(PgHdr *);
int sqlite3PcachePageRefcount(PgHdr*);
int sqlite3PcachePageRefcount(PgHdr *);
/* Return the total number of pages stored in the cache */
int sqlite3PcachePagecount(PCache*);
int sqlite3PcachePagecount(PCache *);
#if defined(SQLITE_CHECK_PAGES) || defined(SQLITE_DEBUG)
/* Iterate through all dirty pages currently stored in the cache. This
@ -141,7 +141,7 @@ void sqlite3PcacheIterateDirty(PCache *pCache, void (*xIter)(PgHdr *));
#if defined(SQLITE_DEBUG)
/* Check invariants on a PgHdr object */
int sqlite3PcachePageSanity(PgHdr*);
int sqlite3PcachePageSanity(PgHdr *);
#endif
/* Set and get the suggested cache-size for the specified pager-cache.
@ -163,7 +163,7 @@ int sqlite3PcacheGetCachesize(PCache *);
int sqlite3PcacheSetSpillsize(PCache *, int);
/* Free up as much memory as possible from the page cache */
void sqlite3PcacheShrink(PCache*);
void sqlite3PcacheShrink(PCache *);
#ifdef SQLITE_ENABLE_MEMORY_MANAGEMENT
/* Try to return memory used by the pcache module to the main memory heap */
@ -171,7 +171,7 @@ int sqlite3PcacheReleaseMemory(int);
#endif
#ifdef SQLITE_TEST
void sqlite3PcacheStats(int*,int*,int*,int*);
void sqlite3PcacheStats(int *, int *, int *, int *);
#endif
void sqlite3PCacheSetDefault(void);
@ -181,10 +181,30 @@ int sqlite3HeaderSizePcache(void);
int sqlite3HeaderSizePcache1(void);
/* Number of dirty pages as a percentage of the configured cache size */
int sqlite3PCachePercentDirty(PCache*);
int sqlite3PCachePercentDirty(PCache *);
#ifdef SQLITE_DIRECT_OVERFLOW_READ
int sqlite3PCacheIsDirty(PCache *pCache);
#endif
// For real implementation of sqlite3_pcache ========================================
typedef struct sqlite3_pcache sqlite3_pcache;
typedef struct sqlite3_pcache_methods2 {
int iVersion;
void *pArg;
int (*xInit)(void *);
void (*xShutdown)(void *);
sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable);
void (*xCachesize)(sqlite3_pcache *, int nCachesize);
int (*xPagecount)(sqlite3_pcache *);
sqlite3_pcache_page *(*xFetch)(sqlite3_pcache *, unsigned key, int createFlag);
void (*xUnpin)(sqlite3_pcache *, sqlite3_pcache_page *, int discard);
void (*xRekey)(sqlite3_pcache *, sqlite3_pcache_page *, unsigned oldKey, unsigned newKey);
void (*xTruncate)(sqlite3_pcache *, unsigned iLimit);
void (*xDestroy)(sqlite3_pcache *);
void (*xShrink)(sqlite3_pcache *);
} sqlite3_pcache_methods2;
extern sqlite3_pcache_methods2 pcache2;
#endif /* _PCACHE_H_ */