Many hyperlinks are disabled.
Use anonymous login
to enable hyperlinks.
Overview
| Comment: | Change an assert() into a NEVER(), since the condition is difficult to prove with certainty. Improved comment on the MemPage.nFree field. |
|---|---|
| Downloads: | Tarball | ZIP archive |
| Timelines: | family | ancestors | descendants | both | deferred-free-space |
| Files: | files | file ages | folders |
| SHA3-256: |
fec071b89df2cbafda365077bb54bc99 |
| User & Date: | drh 2019-02-12 00:58:10.125 |
Context
|
2019-02-12
| ||
| 01:04 | Defer computing the number of bytes of free space on a btree page until that value is actually needed. (check-in: 177f5f40ea user: drh tags: trunk) | |
| 00:58 | Change an assert() into a NEVER(), since the condition is difficult to prove with certainty. Improved comment on the MemPage.nFree field. (Closed-Leaf check-in: fec071b89d user: drh tags: deferred-free-space) | |
|
2019-02-11
| ||
| 22:50 | Do not invoke btreeComputeFreeSpace() when not necessary. (check-in: f11b0ed474 user: drh tags: deferred-free-space) | |
Changes
Changes to src/btree.c.
| ︙ | ︙ | |||
8291 8292 8293 8294 8295 8296 8297 |
VVA_ONLY( int balance_quick_called = 0 );
VVA_ONLY( int balance_deeper_called = 0 );
do {
int iPage = pCur->iPage;
MemPage *pPage = pCur->pPage;
| | | 8291 8292 8293 8294 8295 8296 8297 8298 8299 8300 8301 8302 8303 8304 8305 |
VVA_ONLY( int balance_quick_called = 0 );
VVA_ONLY( int balance_deeper_called = 0 );
do {
int iPage = pCur->iPage;
MemPage *pPage = pCur->pPage;
if( NEVER(pPage->nFree<0) && btreeComputeFreeSpace(pPage) ) break;
if( iPage==0 ){
if( pPage->nOverflow ){
/* The root page of the b-tree is overfull. In this case call the
** balance_deeper() function to create a new child for the root-page
** and copy the current contents of the root-page to it. The
** next iteration of the do-loop will balance the child page.
*/
|
| ︙ | ︙ |
Changes to src/btreeInt.h.
| ︙ | ︙ | |||
282 283 284 285 286 287 288 | u8 hdrOffset; /* 100 for page 1. 0 otherwise */ u8 childPtrSize; /* 0 if leaf==1. 4 if leaf==0 */ u8 max1bytePayload; /* min(maxLocal,127) */ u8 nOverflow; /* Number of overflow cell bodies in aCell[] */ u16 maxLocal; /* Copy of BtShared.maxLocal or BtShared.maxLeaf */ u16 minLocal; /* Copy of BtShared.minLocal or BtShared.minLeaf */ u16 cellOffset; /* Index in aData of first cell pointer */ | | | 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 |
u8 hdrOffset; /* 100 for page 1. 0 otherwise */
u8 childPtrSize; /* 0 if leaf==1. 4 if leaf==0 */
u8 max1bytePayload; /* min(maxLocal,127) */
u8 nOverflow; /* Number of overflow cell bodies in aCell[] */
u16 maxLocal; /* Copy of BtShared.maxLocal or BtShared.maxLeaf */
u16 minLocal; /* Copy of BtShared.minLocal or BtShared.minLeaf */
u16 cellOffset; /* Index in aData of first cell pointer */
int nFree; /* Number of free bytes on the page. -1 for unknown */
u16 nCell; /* Number of cells on this page, local and ovfl */
u16 maskPage; /* Mask for page offset */
u16 aiOvfl[4]; /* Insert the i-th overflow cell before the aiOvfl-th
** non-overflow cell */
u8 *apOvfl[4]; /* Pointers to the body of overflow cells */
BtShared *pBt; /* Pointer to BtShared that this page is part of */
u8 *aData; /* Pointer to disk image of the page data */
|
| ︙ | ︙ |