database/postgres
1
0
Fork 0
mirror of https://github.com/postgres/postgres.git synced 2025-07-31 22:04:40 +03:00
Code Activity

Tweak fillfactor code as per my recent proposal. Fix nbtsort.c so that

Browse Source 
it can handle small fillfactors for ordinary-sized index entries without
failing on large ones; fix nbtinsert.c to distinguish leaf and nonleaf
pages; change the minimum fillfactor to 10% for all index types.
This commit is contained in:
Tom Lane
2006-07-11 21:05:57 +00:00
parent 1be8f80288
commit d29b66882a
7 changed files with 41 additions and 28 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
src/backend/access/gin/ginutil.c
View File

@ -8,7 +8,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/gin/ginutil.c,v 1.3 2006/07/03 22:45:36 tgl Exp $
* $PostgreSQL: pgsql/src/backend/access/gin/ginutil.c,v 1.4 2006/07/11 21:05:57 tgl Exp $
*-------------------------------------------------------------------------
*/
@ -213,7 +213,7 @@ ginoptions(PG_FUNCTION_ARGS)
* It's not clear that fillfactor is useful for GIN, but for the moment
* we'll accept it anyway. (It won't do anything...)
*/
#define GIN_MIN_FILLFACTOR 50
#define GIN_MIN_FILLFACTOR 10
#define GIN_DEFAULT_FILLFACTOR 100
result = default_reloptions(reloptions, validate,

11
src/backend/access/nbtree/nbtinsert.c
View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.139 2006/07/03 22:45:37 tgl Exp $
* $PostgreSQL: pgsql/src/backend/access/nbtree/nbtinsert.c,v 1.140 2006/07/11 21:05:57 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -991,7 +991,8 @@ _bt_split(Relation rel, Buffer buf, OffsetNumber firstright,
* inserting successively increasing keys (consider sequences, 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.
* This is the same as nbtsort.c produces for a newly-created tree.
* This is the same as nbtsort.c produces for a newly-created tree. Note
* that leaf and nonleaf pages use different fillfactors.
*
* 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
@ -1025,10 +1026,14 @@ _bt_findsplitloc(Relation rel,
/* Passed-in newitemsz is MAXALIGNED but does not include line pointer */
newitemsz += sizeof(ItemIdData);
state.newitemsz = newitemsz;
state.fillfactor = RelationGetFillFactor(rel, BTREE_DEFAULT_FILLFACTOR);
state.is_leaf = P_ISLEAF(opaque);
state.is_rightmost = P_RIGHTMOST(opaque);
state.have_split = false;
if (state.is_leaf)
state.fillfactor = RelationGetFillFactor(rel,
BTREE_DEFAULT_FILLFACTOR);
else
state.fillfactor = BTREE_NONLEAF_FILLFACTOR;
/* Total free space available on a btree page, after fixed overhead */
leftspace = rightspace =

26
src/backend/access/nbtree/nbtsort.c
View File

@ -27,10 +27,10 @@
* insertion would cause a split (and not only of the leaf page; the need
* for a split would cascade right up the tree). The steady-state load
* factor for btrees is usually estimated at 70%. We choose to pack leaf
* pages to the user-controllable fill factor while upper pages are always
* packed to 70%. This gives us reasonable density (there aren't many upper
* pages if the keys are reasonable-size) without incurring a lot of cascading
* splits during early insertions.
* pages to the user-controllable fill factor (default 90%) while upper pages
* are always packed to 70%. This gives us reasonable density (there aren't
* many upper pages if the keys are reasonable-size) without risking a lot of
* cascading splits during early insertions.
*
* Formerly the index pages being built were kept in shared buffers, but
* that is of no value (since other backends have no interest in them yet)
@ -57,7 +57,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/access/nbtree/nbtsort.c,v 1.104 2006/07/03 22:45:37 tgl Exp $
* $PostgreSQL: pgsql/src/backend/access/nbtree/nbtsort.c,v 1.105 2006/07/11 21:05:57 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -349,7 +349,7 @@ _bt_pagestate(BTWriteState *wstate, uint32 level)
state->btps_level = level;
/* set "full" threshold based on level. See notes at head of file. */
if (level > 0)
state->btps_full = (BLCKSZ * (100 - BTREE_MIN_FILLFACTOR) / 100);
state->btps_full = (BLCKSZ * (100 - BTREE_NONLEAF_FILLFACTOR) / 100);
else
state->btps_full = RelationGetTargetPageFreeSpace(wstate->index,
BTREE_DEFAULT_FILLFACTOR);
@ -499,11 +499,16 @@ _bt_buildadd(BTWriteState *wstate, BTPageState *state, IndexTuple itup)
"Consider a function index of an MD5 hash of the value, "
"or use full text indexing.")));
if (pgspc < itupsz || pgspc < state->btps_full)
/*
* Check to see if page is "full". It's definitely full if the item
* won't fit. Otherwise, compare to the target freespace derived from
* the fillfactor. However, we must put at least two items on each
* page, so disregard fillfactor if we don't have that many.
*/
if (pgspc < itupsz || (pgspc < state->btps_full && last_off > P_FIRSTKEY))
{
/*
* Item won't fit on this page, or we feel the page is full enough
* already. Finish off the page and write it out.
* Finish off the page and write it out.
*/
Page opage = npage;
BlockNumber oblkno = nblkno;
@ -522,8 +527,7 @@ _bt_buildadd(BTWriteState *wstate, BTPageState *state, IndexTuple itup)
* rearrange the old page so that the 'last item' becomes its high key
* rather than a true data item. There had better be at least two
* items on the page already, else the page would be empty of useful
* data. (Hence, we must allow pages to be packed at least 2/3rds
* full; the 70% figure used above is close to minimum.)
* data.
*/
Assert(last_off > P_FIRSTKEY);
ii = PageGetItemId(opage, last_off);

4
src/include/access/gist_private.h
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/access/gist_private.h,v 1.21 2006/07/11 17:04:13 momjian Exp $
* $PostgreSQL: pgsql/src/include/access/gist_private.h,v 1.22 2006/07/11 21:05:57 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -272,7 +272,7 @@ extern Datum gistgetmulti(PG_FUNCTION_ARGS);
#define GiSTPageSize \
( BLCKSZ - SizeOfPageHeaderData - MAXALIGN(sizeof(GISTPageOpaqueData)) )
#define GIST_MIN_FILLFACTOR 50
#define GIST_MIN_FILLFACTOR 10
#define GIST_DEFAULT_FILLFACTOR 90
extern Datum gistoptions(PG_FUNCTION_ARGS);

4
src/include/access/hash.h
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/access/hash.h,v 1.71 2006/07/03 22:45:39 tgl Exp $
* $PostgreSQL: pgsql/src/include/access/hash.h,v 1.72 2006/07/11 21:05:57 tgl Exp $
*
* NOTES
* modeled after Margo Seltzer's hash implementation for unix.
@ -167,7 +167,7 @@ typedef HashMetaPageData *HashMetaPage;
MAXALIGN(sizeof(HashPageOpaqueData)) - \
sizeof(ItemIdData))
#define HASH_MIN_FILLFACTOR 50
#define HASH_MIN_FILLFACTOR 10
#define HASH_DEFAULT_FILLFACTOR 75
/*

12
src/include/access/nbtree.h
View File

@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2006, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/access/nbtree.h,v 1.100 2006/07/03 22:45:39 tgl Exp $
* $PostgreSQL: pgsql/src/include/access/nbtree.h,v 1.101 2006/07/11 21:05:57 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -107,11 +107,15 @@ typedef struct BTMetaPageData
MAXALIGN(sizeof(BTPageOpaqueData))) / 3 - sizeof(ItemIdData))
/*
* Because of above, min fillfactor can't be less than 2/3rds; see notes in
* nbtsort.c before you change these!
* The leaf-page fillfactor defaults to 90% but is user-adjustable.
* For pages above the leaf level, we use a fixed 70% fillfactor.
* The fillfactor is applied during index build and when splitting
* a rightmost page; when splitting non-rightmost pages we try to
* divide the data equally.
*/
#define BTREE_MIN_FILLFACTOR 70
#define BTREE_MIN_FILLFACTOR 10
#define BTREE_DEFAULT_FILLFACTOR 90
#define BTREE_NONLEAF_FILLFACTOR 70
/*
* Test whether two btree entries are "the same".