diff options
Diffstat (limited to 'src/backend/access/nbtree/nbtsort.c')
| -rw-r--r-- | src/backend/access/nbtree/nbtsort.c | 26 |
1 files changed, 21 insertions, 5 deletions
diff --git a/src/backend/access/nbtree/nbtsort.c b/src/backend/access/nbtree/nbtsort.c index e7293b47b03..05785d98eb5 100644 --- a/src/backend/access/nbtree/nbtsort.c +++ b/src/backend/access/nbtree/nbtsort.c @@ -56,13 +56,14 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/access/nbtree/nbtsort.c,v 1.102 2006/06/27 16:53:02 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/access/nbtree/nbtsort.c,v 1.103 2006/07/02 02:23:19 momjian Exp $ * *------------------------------------------------------------------------- */ #include "postgres.h" +#include "access/genam.h" #include "access/nbtree.h" #include "access/xlog.h" #include "miscadmin.h" @@ -120,6 +121,7 @@ typedef struct BTWriteState static Page _bt_blnewpage(uint32 level); +static Size _bt_full_threshold(Relation index, Size pagesize, bool leaf); static BTPageState *_bt_pagestate(BTWriteState *wstate, uint32 level); static void _bt_slideleft(Page page); static void _bt_sortaddtup(Page page, Size itemsize, @@ -328,6 +330,22 @@ _bt_blwritepage(BTWriteState *wstate, Page page, BlockNumber blkno) } /* + * The steady-state load factor for btrees is usually estimated at 70%. + * We choose to pack leaf pages to 90% and upper pages to 70% as defaults. + */ +static Size +_bt_full_threshold(Relation index, Size pagesize, bool leaf) +{ + int fillfactor = IndexGetFillFactor(index); + if (!leaf) + { + /* XXX: Is this reasonable? */ + fillfactor = Max(70, 3 * fillfactor - 200); + } + return pagesize * (100 - fillfactor) / 100; +} + +/* * allocate and initialize a new BTPageState. the returned structure * is suitable for immediate use by _bt_buildadd. */ @@ -347,10 +365,8 @@ _bt_pagestate(BTWriteState *wstate, uint32 level) state->btps_lastoff = P_HIKEY; state->btps_level = level; /* set "full" threshold based on level. See notes at head of file. */ - if (level > 0) - state->btps_full = (PageGetPageSize(state->btps_page) * 3) / 10; - else - state->btps_full = PageGetPageSize(state->btps_page) / 10; + state->btps_full = _bt_full_threshold(wstate->index, + PageGetPageSize(state->btps_page), level == 0); /* no parent level, yet */ state->btps_next = NULL; |