*** pgsql/src/backend/access/hash/hashpage.c	2009/06/11 14:48:53	1.80
--- pgsql/src/backend/access/hash/hashpage.c	2009/11/01 21:25:32	1.80.2.1
***************
*** 8,14 ****
   *
   *
   * IDENTIFICATION
!  *	  $PostgreSQL: pgsql/src/backend/access/hash/hashpage.c,v 1.79 2009/01/01 17:23:35 momjian Exp $
   *
   * NOTES
   *	  Postgres hash pages look like ordinary relation pages.  The opaque
--- 8,14 ----
   *
   *
   * IDENTIFICATION
!  *	  $PostgreSQL: pgsql/src/backend/access/hash/hashpage.c,v 1.80 2009/06/11 14:48:53 momjian Exp $
   *
   * NOTES
   *	  Postgres hash pages look like ordinary relation pages.  The opaque
*************** _hash_splitbucket(Relation rel,
*** 765,784 ****
  				  uint32 highmask,
  				  uint32 lowmask)
  {
- 	Bucket		bucket;
- 	Buffer		obuf;
- 	Buffer		nbuf;
  	BlockNumber oblkno;
  	BlockNumber nblkno;
! 	HashPageOpaque oopaque;
! 	HashPageOpaque nopaque;
! 	IndexTuple	itup;
! 	Size		itemsz;
! 	OffsetNumber ooffnum;
! 	OffsetNumber noffnum;
! 	OffsetNumber omaxoffnum;
  	Page		opage;
  	Page		npage;
  
  	/*
  	 * It should be okay to simultaneously write-lock pages from each bucket,
--- 765,778 ----
  				  uint32 highmask,
  				  uint32 lowmask)
  {
  	BlockNumber oblkno;
  	BlockNumber nblkno;
! 	Buffer		obuf;
! 	Buffer		nbuf;
  	Page		opage;
  	Page		npage;
+ 	HashPageOpaque oopaque;
+ 	HashPageOpaque nopaque;
  
  	/*
  	 * It should be okay to simultaneously write-lock pages from each bucket,
*************** _hash_splitbucket(Relation rel,
*** 805,899 ****
  	/*
  	 * Partition the tuples in the old bucket between the old bucket and the
  	 * new bucket, advancing along the old bucket's overflow bucket chain and
! 	 * adding overflow pages to the new bucket as needed.
  	 */
- 	ooffnum = FirstOffsetNumber;
- 	omaxoffnum = PageGetMaxOffsetNumber(opage);
  	for (;;)
  	{
! 		/*
! 		 * at each iteration through this loop, each of these variables should
! 		 * be up-to-date: obuf opage oopaque ooffnum omaxoffnum
! 		 */
! 
! 		/* check if we're at the end of the page */
! 		if (ooffnum > omaxoffnum)
  		{
! 			/* at end of page, but check for an(other) overflow page */
! 			oblkno = oopaque->hasho_nextblkno;
! 			if (!BlockNumberIsValid(oblkno))
! 				break;
  
  			/*
! 			 * we ran out of tuples on this particular page, but we have more
! 			 * overflow pages; advance to next page.
  			 */
! 			_hash_wrtbuf(rel, obuf);
  
! 			obuf = _hash_getbuf(rel, oblkno, HASH_WRITE, LH_OVERFLOW_PAGE);
! 			opage = BufferGetPage(obuf);
! 			oopaque = (HashPageOpaque) PageGetSpecialPointer(opage);
! 			ooffnum = FirstOffsetNumber;
! 			omaxoffnum = PageGetMaxOffsetNumber(opage);
! 			continue;
  		}
  
  		/*
! 		 * Fetch the item's hash key (conveniently stored in the item) and
! 		 * determine which bucket it now belongs in.
  		 */
! 		itup = (IndexTuple) PageGetItem(opage, PageGetItemId(opage, ooffnum));
! 		bucket = _hash_hashkey2bucket(_hash_get_indextuple_hashkey(itup),
! 									  maxbucket, highmask, lowmask);
! 
! 		if (bucket == nbucket)
  		{
! 			/*
! 			 * insert the tuple into the new bucket.  if it doesn't fit on the
! 			 * current page in the new bucket, we must allocate a new overflow
! 			 * page and place the tuple on that page instead.
! 			 */
! 			itemsz = IndexTupleDSize(*itup);
! 			itemsz = MAXALIGN(itemsz);
! 
! 			if (PageGetFreeSpace(npage) < itemsz)
! 			{
! 				/* write out nbuf and drop lock, but keep pin */
! 				_hash_chgbufaccess(rel, nbuf, HASH_WRITE, HASH_NOLOCK);
! 				/* chain to a new overflow page */
! 				nbuf = _hash_addovflpage(rel, metabuf, nbuf);
! 				npage = BufferGetPage(nbuf);
! 				/* we don't need nopaque within the loop */
! 			}
! 
! 			noffnum = OffsetNumberNext(PageGetMaxOffsetNumber(npage));
! 			if (PageAddItem(npage, (Item) itup, itemsz, noffnum, false, false)
! 				== InvalidOffsetNumber)
! 				elog(ERROR, "failed to add index item to \"%s\"",
! 					 RelationGetRelationName(rel));
! 
! 			/*
! 			 * now delete the tuple from the old bucket.  after this section
! 			 * of code, 'ooffnum' will actually point to the ItemId to which
! 			 * we would point if we had advanced it before the deletion
! 			 * (PageIndexTupleDelete repacks the ItemId array).  this also
! 			 * means that 'omaxoffnum' is exactly one less than it used to be,
! 			 * so we really can just decrement it instead of calling
! 			 * PageGetMaxOffsetNumber.
! 			 */
! 			PageIndexTupleDelete(opage, ooffnum);
! 			omaxoffnum = OffsetNumberPrev(omaxoffnum);
  		}
  		else
! 		{
! 			/*
! 			 * the tuple stays on this page.  we didn't move anything, so we
! 			 * didn't delete anything and therefore we don't have to change
! 			 * 'omaxoffnum'.
! 			 */
! 			Assert(bucket == obucket);
! 			ooffnum = OffsetNumberNext(ooffnum);
! 		}
  	}
  
  	/*
--- 799,898 ----
  	/*
  	 * Partition the tuples in the old bucket between the old bucket and the
  	 * new bucket, advancing along the old bucket's overflow bucket chain and
! 	 * adding overflow pages to the new bucket as needed.  Outer loop
! 	 * iterates once per page in old bucket.
  	 */
  	for (;;)
  	{
! 		OffsetNumber ooffnum;
! 		OffsetNumber omaxoffnum;
! 		OffsetNumber deletable[MaxOffsetNumber];
! 		int			ndeletable = 0;
! 
! 		/* Scan each tuple in old page */
! 		omaxoffnum = PageGetMaxOffsetNumber(opage);
! 		for (ooffnum = FirstOffsetNumber;
! 			 ooffnum <= omaxoffnum;
! 			 ooffnum = OffsetNumberNext(ooffnum))
  		{
! 			IndexTuple	itup;
! 			Size		itemsz;
! 			Bucket		bucket;
  
  			/*
! 			 * Fetch the item's hash key (conveniently stored in the item) and
! 			 * determine which bucket it now belongs in.
  			 */
! 			itup = (IndexTuple) PageGetItem(opage,
! 											PageGetItemId(opage, ooffnum));
! 			bucket = _hash_hashkey2bucket(_hash_get_indextuple_hashkey(itup),
! 										  maxbucket, highmask, lowmask);
  
! 			if (bucket == nbucket)
! 			{
! 				/*
! 				 * insert the tuple into the new bucket.  if it doesn't fit on
! 				 * the current page in the new bucket, we must allocate a new
! 				 * overflow page and place the tuple on that page instead.
! 				 */
! 				itemsz = IndexTupleDSize(*itup);
! 				itemsz = MAXALIGN(itemsz);
! 
! 				if (PageGetFreeSpace(npage) < itemsz)
! 				{
! 					/* write out nbuf and drop lock, but keep pin */
! 					_hash_chgbufaccess(rel, nbuf, HASH_WRITE, HASH_NOLOCK);
! 					/* chain to a new overflow page */
! 					nbuf = _hash_addovflpage(rel, metabuf, nbuf);
! 					npage = BufferGetPage(nbuf);
! 					/* we don't need nblkno or nopaque within the loop */
! 				}
! 
! 				/*
! 				 * Insert tuple on new page, using _hash_pgaddtup to ensure
! 				 * correct ordering by hashkey.  This is a tad inefficient
! 				 * since we may have to shuffle itempointers repeatedly.
! 				 * Possible future improvement: accumulate all the items for
! 				 * the new page and qsort them before insertion.
! 				 */
! 				(void) _hash_pgaddtup(rel, nbuf, itemsz, itup);
! 
! 				/*
! 				 * Mark tuple for deletion from old page.
! 				 */
! 				deletable[ndeletable++] = ooffnum;
! 			}
! 			else
! 			{
! 				/*
! 				 * the tuple stays on this page, so nothing to do.
! 				 */
! 				Assert(bucket == obucket);
! 			}
  		}
  
+ 		oblkno = oopaque->hasho_nextblkno;
+ 
  		/*
! 		 * Done scanning this old page.  If we moved any tuples, delete them
! 		 * from the old page.
  		 */
! 		if (ndeletable > 0)
  		{
! 			PageIndexMultiDelete(opage, deletable, ndeletable);
! 			_hash_wrtbuf(rel, obuf);
  		}
  		else
! 			_hash_relbuf(rel, obuf);
! 
! 		/* Exit loop if no more overflow pages in old bucket */
! 		if (!BlockNumberIsValid(oblkno))
! 			break;
! 
! 		/* Else, advance to next old page */
! 		obuf = _hash_getbuf(rel, oblkno, HASH_WRITE, LH_OVERFLOW_PAGE);
! 		opage = BufferGetPage(obuf);
! 		oopaque = (HashPageOpaque) PageGetSpecialPointer(opage);
  	}
  
  	/*
*************** _hash_splitbucket(Relation rel,
*** 902,908 ****
  	 * tuples remaining in the old bucket (including the overflow pages) are
  	 * packed as tightly as possible.  The new bucket is already tight.
  	 */
- 	_hash_wrtbuf(rel, obuf);
  	_hash_wrtbuf(rel, nbuf);
  
  	_hash_squeezebucket(rel, obucket, start_oblkno, NULL);
--- 901,906 ----