diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
index 042a33a5d2bc6fd7a7109763057037b32dceeb65..71ba6d2e52ef25d94b00820e2803fa24b9d21751 100644
--- a/src/backend/access/heap/heapam.c
+++ b/src/backend/access/heap/heapam.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/access/heap/heapam.c,v 1.226 2007/02/04 20:00:37 tgl Exp $
+ * $PostgreSQL: pgsql/src/backend/access/heap/heapam.c,v 1.227 2007/02/05 04:22:18 tgl Exp $
*
*
* INTERFACE ROUTINES
@@ -3463,7 +3463,7 @@ heap_xlog_insert(XLogRecPtr lsn, XLogRecord *record)
struct
{
HeapTupleHeaderData hdr;
- char data[MaxTupleSize];
+ char data[MaxHeapTupleSize];
} tbuf;
HeapTupleHeader htup;
xl_heap_header xlhdr;
@@ -3505,7 +3505,7 @@ heap_xlog_insert(XLogRecPtr lsn, XLogRecord *record)
elog(PANIC, "heap_insert_redo: invalid max offset number");
newlen = record->xl_len - SizeOfHeapInsert - SizeOfHeapHeader;
- Assert(newlen <= MaxTupleSize);
+ Assert(newlen <= MaxHeapTupleSize);
memcpy((char *) &xlhdr,
(char *) xlrec + SizeOfHeapInsert,
SizeOfHeapHeader);
@@ -3551,7 +3551,7 @@ heap_xlog_update(XLogRecPtr lsn, XLogRecord *record, bool move)
struct
{
HeapTupleHeaderData hdr;
- char data[MaxTupleSize];
+ char data[MaxHeapTupleSize];
} tbuf;
xl_heap_header xlhdr;
int hsize;
@@ -3668,7 +3668,7 @@ newsame:;
hsize += (2 * sizeof(TransactionId));
newlen = record->xl_len - hsize;
- Assert(newlen <= MaxTupleSize);
+ Assert(newlen <= MaxHeapTupleSize);
memcpy((char *) &xlhdr,
(char *) xlrec + SizeOfHeapUpdate,
SizeOfHeapHeader);
diff --git a/src/backend/access/heap/hio.c b/src/backend/access/heap/hio.c
index 4e033be4e0d31442bf3e81205bfcfb7622d2f044..0bb617a8cdcd2b4f3863e78112f914312a581c4b 100644
--- a/src/backend/access/heap/hio.c
+++ b/src/backend/access/heap/hio.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/access/heap/hio.c,v 1.64 2007/01/05 22:19:22 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/access/heap/hio.c,v 1.65 2007/02/05 04:22:18 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -118,12 +118,12 @@ RelationGetBufferForTuple(Relation relation, Size len,
/*
* If we're gonna fail for oversize tuple, do it right away
*/
- if (len > MaxTupleSize)
+ if (len > MaxHeapTupleSize)
ereport(ERROR,
(errcode(ERRCODE_PROGRAM_LIMIT_EXCEEDED),
errmsg("row is too big: size %lu, maximum size %lu",
(unsigned long) len,
- (unsigned long) MaxTupleSize)));
+ (unsigned long) MaxHeapTupleSize)));
/* Compute desired extra freespace due to fillfactor option */
saveFreeSpace = RelationGetTargetPageFreeSpace(relation,
@@ -147,7 +147,7 @@ RelationGetBufferForTuple(Relation relation, Size len,
* When use_fsm is false, we either put the tuple onto the existing target
* page or extend the relation.
*/
- if (len + saveFreeSpace <= MaxTupleSize)
+ if (len + saveFreeSpace <= MaxHeapTupleSize)
targetBlock = relation->rd_targblock;
else
{
diff --git a/src/backend/commands/vacuum.c b/src/backend/commands/vacuum.c
index 43647d7989fc12da5365981984779e26b454df0d..5f9f787eeea4be7c7be98a0c2f349668ab0f165a 100644
--- a/src/backend/commands/vacuum.c
+++ b/src/backend/commands/vacuum.c
@@ -13,7 +13,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/commands/vacuum.c,v 1.344 2007/02/01 19:10:26 momjian Exp $
+ * $PostgreSQL: pgsql/src/backend/commands/vacuum.c,v 1.345 2007/02/05 04:22:18 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -1236,7 +1236,7 @@ scan_heap(VRelStats *vacrelstats, Relation onerel,
nunused;
double free_space,
usable_free_space;
- Size min_tlen = MaxTupleSize;
+ Size min_tlen = MaxHeapTupleSize;
Size max_tlen = 0;
bool do_shrinking = true;
VTupleLink vtlinks = (VTupleLink) palloc(100 * sizeof(VTupleLinkData));
diff --git a/src/include/access/htup.h b/src/include/access/htup.h
index ddde6a466d1a30f8880368c39b2b8ec2dc559ccf..eecc6959e89a424187216d4e94eb5e10301450af 100644
--- a/src/include/access/htup.h
+++ b/src/include/access/htup.h
@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/access/htup.h,v 1.89 2007/01/09 22:01:00 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/access/htup.h,v 1.90 2007/02/05 04:22:18 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -314,19 +314,17 @@ do { \
#define BITMAPLEN(NATTS) (((int)(NATTS) + 7) / 8)
/*
- * MaxTupleSize is the maximum allowed size of a tuple, including header and
- * MAXALIGN alignment padding. Basically it's BLCKSZ minus the other stuff
- * that has to be on a disk page. The "other stuff" includes access-method-
- * dependent "special space", which we assume will be no more than
- * MaxSpecialSpace bytes (currently, on heap pages it's actually zero).
+ * MaxHeapTupleSize is the maximum allowed size of a heap tuple, including
+ * header and MAXALIGN alignment padding. Basically it's BLCKSZ minus the
+ * other stuff that has to be on a disk page. Since heap pages use no
+ * "special space", there's no deduction for that.
*
* NOTE: we do not need to count an ItemId for the tuple because
- * sizeof(PageHeaderData) includes the first ItemId on the page.
+ * sizeof(PageHeaderData) includes the first ItemId on the page. But beware
+ * of assuming that, say, you can fit 2 tuples of size MaxHeapTupleSize/2
+ * on the same page.
*/
-#define MaxSpecialSpace 32
-
-#define MaxTupleSize \
- (BLCKSZ - MAXALIGN(sizeof(PageHeaderData) + MaxSpecialSpace))
+#define MaxHeapTupleSize (BLCKSZ - MAXALIGN(sizeof(PageHeaderData)))
/*
* MaxHeapTuplesPerPage is an upper bound on the number of tuples that can
diff --git a/src/include/access/nbtree.h b/src/include/access/nbtree.h
index 574aec496f8c0d56f1bea005d4b1ff86408407f6..91d91a77053dfb73c6a1669c3772dd4284d16670 100644
--- a/src/include/access/nbtree.h
+++ b/src/include/access/nbtree.h
@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/access/nbtree.h,v 1.109 2007/01/20 18:43:35 neilc Exp $
+ * $PostgreSQL: pgsql/src/include/access/nbtree.h,v 1.110 2007/02/05 04:22:18 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -99,13 +99,18 @@ typedef struct BTMetaPageData
#define BTREE_VERSION 2 /* current version number */
/*
+ * Maximum size of a btree index entry, including its tuple header.
+ *
* We actually need to be able to fit three items on every page,
* so restrict any one item to 1/3 the per-page available space.
+ *
+ * Note: sizeof(PageHeaderData) includes the first ItemId, but we have
+ * to allow for 2 more, as well as the end-of-page special space.
*/
#define BTMaxItemSize(page) \
- ((PageGetPageSize(page) - \
- sizeof(PageHeaderData) - \
- MAXALIGN(sizeof(BTPageOpaqueData))) / 3 - sizeof(ItemIdData))
+ MAXALIGN_DOWN((PageGetPageSize(page) - \
+ MAXALIGN(sizeof(PageHeaderData) + 2*sizeof(ItemIdData)) - \
+ MAXALIGN(sizeof(BTPageOpaqueData))) / 3)
/*
* The leaf-page fillfactor defaults to 90% but is user-adjustable.
diff --git a/src/include/access/tuptoaster.h b/src/include/access/tuptoaster.h
index 49d69836dcd79e95e9606e31b5a20324a0e1d8e4..3693379dba72edb0312539daa41b1dd123aee3c1 100644
--- a/src/include/access/tuptoaster.h
+++ b/src/include/access/tuptoaster.h
@@ -6,7 +6,7 @@
*
* Copyright (c) 2000-2007, PostgreSQL Global Development Group
*
- * $PostgreSQL: pgsql/src/include/access/tuptoaster.h,v 1.31 2007/02/04 20:00:37 tgl Exp $
+ * $PostgreSQL: pgsql/src/include/access/tuptoaster.h,v 1.32 2007/02/05 04:22:18 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -29,40 +29,47 @@
* TOAST_TUPLE_TARGET bytes. Both numbers include all tuple header overhead
* and between-fields alignment padding, but we do *not* consider any
* end-of-tuple alignment padding; hence the values can be compared directly
- * to a tuple's t_len field. (Note that the symbol values are not
- * necessarily MAXALIGN multiples.)
+ * to a tuple's t_len field. We choose TOAST_TUPLE_THRESHOLD with the
+ * knowledge that toast-table tuples will be exactly that size, and we'd
+ * like to fit four of them per page with minimal space wastage.
*
* The numbers need not be the same, though they currently are.
+ *
+ * Note: sizeof(PageHeaderData) includes the first ItemId, but we have
+ * to allow for 3 more, if we want to fit 4 tuples on a page.
*/
-#define TOAST_TUPLE_THRESHOLD (MaxTupleSize / 4)
+#define TOAST_TUPLE_THRESHOLD \
+ MAXALIGN_DOWN((BLCKSZ - \
+ MAXALIGN(sizeof(PageHeaderData) + 3 * sizeof(ItemIdData))) \
+ / 4)
-#define TOAST_TUPLE_TARGET (MaxTupleSize / 4)
+#define TOAST_TUPLE_TARGET TOAST_TUPLE_THRESHOLD
/*
* If an index value is larger than TOAST_INDEX_TARGET, we will try to
* compress it (we can't move it out-of-line, however). Note that this
* number is per-datum, not per-tuple, for simplicity in index_form_tuple().
*/
-#define TOAST_INDEX_TARGET (MaxTupleSize / 16)
+#define TOAST_INDEX_TARGET (MaxHeapTupleSize / 16)
/*
* When we store an oversize datum externally, we divide it into chunks
* containing at most TOAST_MAX_CHUNK_SIZE data bytes. This number *must*
* be small enough that the completed toast-table tuple (including the
- * ID and sequence fields and all overhead) is no more than MaxTupleSize
+ * ID and sequence fields and all overhead) is no more than MaxHeapTupleSize
* bytes. It *should* be small enough to make toast-table tuples no more
* than TOAST_TUPLE_THRESHOLD bytes, else heapam.c will uselessly invoke
- * the toaster on toast-table tuples.
+ * the toaster on toast-table tuples. The current coding ensures that the
+ * maximum tuple length is exactly TOAST_TUPLE_THRESHOLD bytes.
*
* NB: you cannot change this value without forcing initdb, at least not
* if your DB contains any multi-chunk toasted values.
*/
#define TOAST_MAX_CHUNK_SIZE (TOAST_TUPLE_THRESHOLD - \
- MAXALIGN( \
- MAXALIGN(offsetof(HeapTupleHeaderData, t_bits)) + \
- sizeof(Oid) + \
- sizeof(int32) + \
- VARHDRSZ))
+ MAXALIGN(offsetof(HeapTupleHeaderData, t_bits)) - \
+ sizeof(Oid) - \
+ sizeof(int32) - \
+ VARHDRSZ)
/* ----------
diff --git a/src/include/c.h b/src/include/c.h
index 9daa9e4c0eb00a149f0c9aa29510c2a533b34827..0774ec7cc1e636ad7706d8763de802e905102c4f 100644
--- a/src/include/c.h
+++ b/src/include/c.h
@@ -12,7 +12,7 @@
* Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/c.h,v 1.217 2007/01/25 03:30:43 momjian Exp $
+ * $PostgreSQL: pgsql/src/include/c.h,v 1.218 2007/02/05 04:22:18 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -537,12 +537,12 @@ typedef NameData *Name;
/* ----------------
* Alignment macros: align a length or address appropriately for a given type.
+ * The fooALIGN() macros round up to a multiple of the required alignment,
+ * while the fooALIGN_DOWN() macros round down. The latter are more useful
+ * for problems like "how many X-sized structures will fit in a page?".
*
- * There used to be some incredibly crufty platform-dependent hackery here,
- * but now we rely on the configure script to get the info for us. Much nicer.
- *
- * NOTE: TYPEALIGN will not work if ALIGNVAL is not a power of 2.
- * That case seems extremely unlikely to occur in practice, however.
+ * NOTE: TYPEALIGN[_DOWN] will not work if ALIGNVAL is not a power of 2.
+ * That case seems extremely unlikely to be needed in practice, however.
* ----------------
*/
@@ -557,6 +557,14 @@ typedef NameData *Name;
/* MAXALIGN covers only built-in types, not buffers */
#define BUFFERALIGN(LEN) TYPEALIGN(ALIGNOF_BUFFER, (LEN))
+#define TYPEALIGN_DOWN(ALIGNVAL,LEN) \
+ (((long) (LEN)) & ~((long) ((ALIGNVAL) - 1)))
+
+#define SHORTALIGN_DOWN(LEN) TYPEALIGN_DOWN(ALIGNOF_SHORT, (LEN))
+#define INTALIGN_DOWN(LEN) TYPEALIGN_DOWN(ALIGNOF_INT, (LEN))
+#define LONGALIGN_DOWN(LEN) TYPEALIGN_DOWN(ALIGNOF_LONG, (LEN))
+#define DOUBLEALIGN_DOWN(LEN) TYPEALIGN_DOWN(ALIGNOF_DOUBLE, (LEN))
+#define MAXALIGN_DOWN(LEN) TYPEALIGN_DOWN(MAXIMUM_ALIGNOF, (LEN))
/* ----------------------------------------------------------------
* Section 6: widely useful macros
diff --git a/src/include/catalog/catversion.h b/src/include/catalog/catversion.h
index 2f1bb8ae1a46e36f7e94b944dca9ba38894cdda5..6aebea61dd990317570d1294bcd9316245d76f37 100644
--- a/src/include/catalog/catversion.h
+++ b/src/include/catalog/catversion.h
@@ -37,7 +37,7 @@
* Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
- * $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.379 2007/02/03 14:06:55 petere Exp $
+ * $PostgreSQL: pgsql/src/include/catalog/catversion.h,v 1.380 2007/02/05 04:22:18 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@@ -53,6 +53,6 @@
*/
/* yyyymmddN */
-#define CATALOG_VERSION_NO 200702031
+#define CATALOG_VERSION_NO 200702041
#endif