diff options
Diffstat (limited to 'src/backend/access/nbtree/nbtinsert.c')
| -rw-r--r-- | src/backend/access/nbtree/nbtinsert.c | 21 |
1 files changed, 11 insertions, 10 deletions
diff --git a/src/backend/access/nbtree/nbtinsert.c b/src/backend/access/nbtree/nbtinsert.c index 89f8810bde5..3b78843101e 100644 --- a/src/backend/access/nbtree/nbtinsert.c +++ b/src/backend/access/nbtree/nbtinsert.c @@ -8,13 +8,14 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.137 2006/05/08 00:00:09 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.138 2006/07/02 02:23:18 momjian Exp $ * *------------------------------------------------------------------------- */ #include "postgres.h" +#include "access/genam.h" #include "access/heapam.h" #include "access/nbtree.h" #include "miscadmin.h" @@ -25,6 +26,7 @@ typedef struct { /* context data for _bt_checksplitloc */ Size newitemsz; /* size of new item to be inserted */ + int fillfactor; /* used when insert at right most */ bool is_leaf; /* T if splitting a leaf page */ bool is_rightmost; /* T if splitting a rightmost page */ @@ -986,14 +988,11 @@ _bt_split(Relation rel, Buffer buf, OffsetNumber firstright, * it needs to go into!) * * If the page is the rightmost page on its level, we instead try to arrange - * for twice as much free space on the right as on the left. In this way, + * for reserving (100-fillfactor)% of free space on left page. In this way, * when we are inserting successively increasing keys (consider sequences, - * timestamps, etc) we will end up with a tree whose pages are about 67% full, + * timestamps, etc) we will end up with a tree whose pages are about fillfactor% full, * instead of the 50% full result that we'd get without this special case. - * (We could bias it even further to make the initially-loaded tree more full. - * But since the steady-state load for a btree is about 70%, we'd likely just - * be making more page-splitting work for ourselves later on, when we start - * seeing updates to existing tuples.) + * This is the same as initially-loaded tree. * * We are passed the intended insert position of the new tuple, expressed as * the offsetnumber of the tuple it must go in front of. (This could be @@ -1027,6 +1026,7 @@ _bt_findsplitloc(Relation rel, /* Passed-in newitemsz is MAXALIGNED but does not include line pointer */ newitemsz += sizeof(ItemIdData); state.newitemsz = newitemsz; + state.fillfactor = IndexGetFillFactor(rel); state.is_leaf = P_ISLEAF(opaque); state.is_rightmost = P_RIGHTMOST(opaque); state.have_split = false; @@ -1157,10 +1157,11 @@ _bt_checksplitloc(FindSplitData *state, OffsetNumber firstright, if (state->is_rightmost) { /* - * On a rightmost page, try to equalize right free space with - * twice the left free space. See comments for _bt_findsplitloc. + * On a rightmost page, try to reserve (100-fillfactor)% of + * free space on left page. See comments for _bt_findsplitloc. */ - delta = (2 * leftfree) - rightfree; + delta = (state->fillfactor * leftfree) + - ((100 - state->fillfactor) * rightfree); } else { |