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more TDB

This commit is contained in:
Hongze Cheng 2022-03-28 08:58:09 +00:00
parent 27a567543b
commit 387936e437
3 changed files with 16 additions and 11 deletions
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14
source/libs/tdb/src/db/tdbBtree.c
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@ -30,7 +30,6 @@ struct SBTree {
int valLen;
SPager *pPager;
FKeyComparator kcmpr;
u8 fanout;
int pageSize;
int maxLocal;
int minLocal;
@ -100,21 +99,14 @@ int tdbBtreeOpen(int keyLen, int valLen, SPager *pPager, FKeyComparator kcmpr, S
pBt->pPager = pPager;
// pBt->kcmpr
pBt->kcmpr = kcmpr ? kcmpr : tdbDefaultKeyCmprFn;
// pBt->fanout
if (keyLen == TDB_VARIANT_LEN) {
pBt->fanout = TDB_DEFAULT_FANOUT;
} else {
ASSERT(0);
// TODO: pBt->fanout = 0;
}
// pBt->pageSize
pBt->pageSize = tdbPagerGetPageSize(pPager);
// pBt->maxLocal
pBt->maxLocal = (pBt->pageSize - 14) / pBt->fanout;
pBt->maxLocal = tdbPageCapacity(pBt->pageSize, sizeof(SIntHdr)) / 4;
// pBt->minLocal: Should not be allowed smaller than 15, which is [nPayload][nKey][nData]
pBt->minLocal = (pBt->pageSize - 14) / pBt->fanout / 2;
pBt->minLocal = pBt->maxLocal / 2;
// pBt->maxLeaf
pBt->maxLeaf = pBt->pageSize - 14;
pBt->maxLeaf = tdbPageCapacity(pBt->pageSize, sizeof(SLeafHdr));
// pBt->minLeaf
pBt->minLeaf = pBt->minLocal;

1
source/libs/tdb/src/inc/tdbPage.h
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@ -111,6 +111,7 @@ void tdbPageInit(SPage *pPage, u8 szAmHdr, int (*xCellSize)(const SPage *, SCell
int tdbPageInsertCell(SPage *pPage, int idx, SCell *pCell, int szCell, u8 asOvfl);
int tdbPageDropCell(SPage *pPage, int idx);
void tdbPageCopy(SPage *pFromPage, SPage *pToPage);
int tdbPageCapacity(int pageSize, int amHdrSize);
static inline SCell *tdbPageGetCell(SPage *pPage, int idx) {
SCell *pCell;

12
source/libs/tdb/src/page/tdbPage.c
View File

@ -242,6 +242,18 @@ void tdbPageCopy(SPage *pFromPage, SPage *pToPage) {
pToPage->nOverflow = pFromPage->nOverflow;
}
int tdbPageCapacity(int pageSize, int amHdrSize) {
int szPageHdr;
if (pageSize < 65536) {
szPageHdr = pageMethods.szPageHdr;
} else {
szPageHdr = pageLargeMethods.szPageHdr;
}
return pageSize - szPageHdr - amHdrSize;
}
static int tdbPageAllocate(SPage *pPage, int szCell, SCell **ppCell) {
SCell *pFreeCell;
u8 *pOffset;