diff options
Diffstat (limited to 'src/backend/storage/freespace/freespace.c')
| -rw-r--r-- | src/backend/storage/freespace/freespace.c | 107 |
1 files changed, 94 insertions, 13 deletions
diff --git a/src/backend/storage/freespace/freespace.c b/src/backend/storage/freespace/freespace.c index dd8ae526444..7eb4f3ee930 100644 --- a/src/backend/storage/freespace/freespace.c +++ b/src/backend/storage/freespace/freespace.c @@ -108,7 +108,9 @@ static Size fsm_space_cat_to_avail(uint8 cat); static int fsm_set_and_search(Relation rel, FSMAddress addr, uint16 slot, uint8 newValue, uint8 minValue); static BlockNumber fsm_search(Relation rel, uint8 min_cat); -static uint8 fsm_vacuum_page(Relation rel, FSMAddress addr, bool *eof); +static uint8 fsm_vacuum_page(Relation rel, FSMAddress addr, + BlockNumber start, BlockNumber end, + bool *eof); static BlockNumber fsm_get_lastblckno(Relation rel, FSMAddress addr); static void fsm_update_recursive(Relation rel, FSMAddress addr, uint8 new_cat); @@ -370,21 +372,48 @@ FreeSpaceMapTruncateRel(Relation rel, BlockNumber nblocks) */ if (rel->rd_smgr) rel->rd_smgr->smgr_fsm_nblocks = new_nfsmblocks; + + /* + * Update upper-level FSM pages to account for the truncation. This is + * important because the just-truncated pages were likely marked as + * all-free, and would be preferentially selected. + */ + FreeSpaceMapVacuumRange(rel, nblocks, InvalidBlockNumber); } /* - * FreeSpaceMapVacuum - scan and fix any inconsistencies in the FSM + * FreeSpaceMapVacuum - update upper-level pages in the rel's FSM + * + * We assume that the bottom-level pages have already been updated with + * new free-space information. */ void FreeSpaceMapVacuum(Relation rel) { bool dummy; - /* - * Traverse the tree in depth-first order. The tree is stored physically - * in depth-first order, so this should be pretty I/O efficient. - */ - fsm_vacuum_page(rel, FSM_ROOT_ADDRESS, &dummy); + /* Recursively scan the tree, starting at the root */ + (void) fsm_vacuum_page(rel, FSM_ROOT_ADDRESS, + (BlockNumber) 0, InvalidBlockNumber, + &dummy); +} + +/* + * FreeSpaceMapVacuumRange - update upper-level pages in the rel's FSM + * + * As above, but assume that only heap pages between start and end-1 inclusive + * have new free-space information, so update only the upper-level slots + * covering that block range. end == InvalidBlockNumber is equivalent to + * "all the rest of the relation". + */ +void +FreeSpaceMapVacuumRange(Relation rel, BlockNumber start, BlockNumber end) +{ + bool dummy; + + /* Recursively scan the tree, starting at the root */ + if (end > start) + (void) fsm_vacuum_page(rel, FSM_ROOT_ADDRESS, start, end, &dummy); } /******** Internal routines ********/ @@ -783,9 +812,21 @@ fsm_search(Relation rel, uint8 min_cat) /* * Recursive guts of FreeSpaceMapVacuum + * + * Examine the FSM page indicated by addr, as well as its children, updating + * upper-level nodes that cover the heap block range from start to end-1. + * (It's okay if end is beyond the actual end of the map.) + * Return the maximum freespace value on this page. + * + * If addr is past the end of the FSM, set *eof_p to true and return 0. + * + * This traverses the tree in depth-first order. The tree is stored + * physically in depth-first order, so this should be pretty I/O efficient. */ static uint8 -fsm_vacuum_page(Relation rel, FSMAddress addr, bool *eof_p) +fsm_vacuum_page(Relation rel, FSMAddress addr, + BlockNumber start, BlockNumber end, + bool *eof_p) { Buffer buf; Page page; @@ -804,15 +845,52 @@ fsm_vacuum_page(Relation rel, FSMAddress addr, bool *eof_p) page = BufferGetPage(buf); /* - * Recurse into children, and fix the information stored about them at - * this level. + * If we're above the bottom level, recurse into children, and fix the + * information stored about them at this level. */ if (addr.level > FSM_BOTTOM_LEVEL) { - int slot; + FSMAddress fsm_start, + fsm_end; + uint16 fsm_start_slot, + fsm_end_slot; + int slot, + start_slot, + end_slot; bool eof = false; - for (slot = 0; slot < SlotsPerFSMPage; slot++) + /* + * Compute the range of slots we need to update on this page, given + * the requested range of heap blocks to consider. The first slot to + * update is the one covering the "start" block, and the last slot is + * the one covering "end - 1". (Some of this work will be duplicated + * in each recursive call, but it's cheap enough to not worry about.) + */ + fsm_start = fsm_get_location(start, &fsm_start_slot); + fsm_end = fsm_get_location(end - 1, &fsm_end_slot); + + while (fsm_start.level < addr.level) + { + fsm_start = fsm_get_parent(fsm_start, &fsm_start_slot); + fsm_end = fsm_get_parent(fsm_end, &fsm_end_slot); + } + Assert(fsm_start.level == addr.level); + + if (fsm_start.logpageno == addr.logpageno) + start_slot = fsm_start_slot; + else if (fsm_start.logpageno > addr.logpageno) + start_slot = SlotsPerFSMPage; /* shouldn't get here... */ + else + start_slot = 0; + + if (fsm_end.logpageno == addr.logpageno) + end_slot = fsm_end_slot; + else if (fsm_end.logpageno > addr.logpageno) + end_slot = SlotsPerFSMPage - 1; + else + end_slot = -1; /* shouldn't get here... */ + + for (slot = start_slot; slot <= end_slot; slot++) { int child_avail; @@ -820,7 +898,9 @@ fsm_vacuum_page(Relation rel, FSMAddress addr, bool *eof_p) /* After we hit end-of-file, just clear the rest of the slots */ if (!eof) - child_avail = fsm_vacuum_page(rel, fsm_get_child(addr, slot), &eof); + child_avail = fsm_vacuum_page(rel, fsm_get_child(addr, slot), + start, end, + &eof); else child_avail = 0; @@ -835,6 +915,7 @@ fsm_vacuum_page(Relation rel, FSMAddress addr, bool *eof_p) } } + /* Now get the maximum value on the page, to return to caller */ max_avail = fsm_get_max_avail(BufferGetPage(buf)); /* |