gist_choose_bloat-0.1.patch

*** a/src/backend/access/gist/gistutil.c
--- b/src/backend/access/gist/gistutil.c
***************
*** 372,387 **** gistchoose(Relation r, Page p, IndexTuple it,	/* it has compressed entry */
  	OffsetNumber maxoff;
  	OffsetNumber i;
  	OffsetNumber which;
! 	float		sum_grow,
! 				which_grow[INDEX_MAX_KEYS];
  	GISTENTRY	entry,
  				identry[INDEX_MAX_KEYS];
  	bool		isnull[INDEX_MAX_KEYS];
  
  	maxoff = PageGetMaxOffsetNumber(p);
  	*which_grow = -1.0;
  	which = InvalidOffsetNumber;
- 	sum_grow = 1;
  	gistDeCompressAtt(giststate, r,
  					  it, NULL, (OffsetNumber) 0,
  					  identry, isnull);
--- 372,386 ----
  	OffsetNumber maxoff;
  	OffsetNumber i;
  	OffsetNumber which;
! 	float		which_grow[INDEX_MAX_KEYS];
  	GISTENTRY	entry,
  				identry[INDEX_MAX_KEYS];
  	bool		isnull[INDEX_MAX_KEYS];
+ 	int			same_count = 1;
  
  	maxoff = PageGetMaxOffsetNumber(p);
  	*which_grow = -1.0;
  	which = InvalidOffsetNumber;
  	gistDeCompressAtt(giststate, r,
  					  it, NULL, (OffsetNumber) 0,
  					  identry, isnull);
***************
*** 389,400 **** gistchoose(Relation r, Page p, IndexTuple it,	/* it has compressed entry */
  	Assert(maxoff >= FirstOffsetNumber);
  	Assert(!GistPageIsLeaf(p));
  
! 	for (i = FirstOffsetNumber; i <= maxoff && sum_grow; i = OffsetNumberNext(i))
  	{
  		int			j;
  		IndexTuple	itup = (IndexTuple) PageGetItem(p, PageGetItemId(p, i));
  
- 		sum_grow = 0;
  		for (j = 0; j < r->rd_att->natts; j++)
  		{
  			Datum		datum;
--- 388,398 ----
  	Assert(maxoff >= FirstOffsetNumber);
  	Assert(!GistPageIsLeaf(p));
  
! 	for (i = FirstOffsetNumber; i <= maxoff; i = OffsetNumberNext(i))
  	{
  		int			j;
  		IndexTuple	itup = (IndexTuple) PageGetItem(p, PageGetItemId(p, i));
  
  		for (j = 0; j < r->rd_att->natts; j++)
  		{
  			Datum		datum;
***************
*** 411,425 **** gistchoose(Relation r, Page p, IndexTuple it,	/* it has compressed entry */
  			{
  				which = i;
  				which_grow[j] = usize;
! 				if (j < r->rd_att->natts - 1 && i == FirstOffsetNumber)
  					which_grow[j + 1] = -1;
- 				sum_grow += which_grow[j];
  			}
  			else if (which_grow[j] == usize)
! 				sum_grow += usize;
  			else
  			{
- 				sum_grow = 1;
  				break;
  			}
  		}
--- 409,429 ----
  			{
  				which = i;
  				which_grow[j] = usize;
! 				same_count = 1;
! 				if (j < r->rd_att->natts - 1)
  					which_grow[j + 1] = -1;
  			}
  			else if (which_grow[j] == usize)
! 			{
! 				if (j == r->rd_att->natts - 1)
! 				{
! 					same_count++;
! 					if ((rand() % same_count) == 0)
! 						which = i;
! 				}
! 			}				
  			else
  			{
  				break;
  			}
  		}