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Postgres FD Implementation
Commit 97bfffe5 authored by Bruce Momjian's avatar Bruce Momjian
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This patch, which is built upon the "HeapTupleHeader accessor macros" 

patch from 2002-06-10, is supposed to reduce the heap tuple header size
by four bytes on most architectures.  Of course it changes the on-disk
tuple format and therefore requires initdb.

This overlays cmin/cmax/xmax fields into only two fields.

Manfred Koizar
parent 86610398
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Inline Side-by-side
Showing with 90 additions and 31 deletions
src/backend/access/heap/heapam.c
View file @ 97bfffe5
......@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/access/heap/heapam.c,v 1.139 2002/06/20 20:29:24 momjian Exp $
* $Header: /cvsroot/pgsql/src/backend/access/heap/heapam.c,v 1.140 2002/07/02 05:46:14 momjian Exp $
*
*
* INTERFACE ROUTINES
......@@ -2204,7 +2204,7 @@ heap_xlog_insert(bool redo, XLogRecPtr lsn, XLogRecord *record)
htup->t_infomask = HEAP_XMAX_INVALID | xlhdr.mask;
HeapTupleHeaderSetXmin(htup, record->xl_xid);
HeapTupleHeaderSetCmin(htup, FirstCommandId);
HeapTupleHeaderSetXmax(htup, InvalidTransactionId);
HeapTupleHeaderSetXmaxInvalid(htup);
HeapTupleHeaderSetCmax(htup, FirstCommandId);
offnum = PageAddItem(page, (Item) htup, newlen, offnum,
......
src/include/access/htup.h
View file @ 97bfffe5
......@@ -7,7 +7,7 @@
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: htup.h,v 1.54 2002/06/20 20:29:43 momjian Exp $
* $Id: htup.h,v 1.55 2002/07/02 05:46:14 momjian Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -57,15 +57,24 @@
* Also note that we omit the nulls bitmap if t_infomask shows that there
* are no nulls in the tuple.
*/
/*
** We store five "virtual" fields Xmin, Cmin, Xmax, Cmax, and Xvac
** in three physical fields t_xmin, t_cid, t_xmax:
** CommandId Cmin; insert CID stamp
** CommandId Cmax; delete CommandId stamp
** TransactionId Xmin; insert XID stamp
** TransactionId Xmax; delete XID stamp
** TransactionId Xvac; used by VACCUUM
**
** This assumes, that a CommandId can be stored in a TransactionId.
*/
typedef struct HeapTupleHeaderData
{
Oid t_oid; /* OID of this tuple -- 4 bytes */
CommandId t_cmin; /* insert CID stamp -- 4 bytes each */
CommandId t_cmax; /* delete CommandId stamp */
TransactionId t_xmin; /* insert XID stamp -- 4 bytes each */
TransactionId t_xmax; /* delete XID stamp */
TransactionId t_xmin; /* Xmin -- 4 bytes each */
TransactionId t_cid; /* Cmin, Cmax, Xvac */
TransactionId t_xmax; /* Xmax, Cmax */
ItemPointerData t_ctid; /* current TID of this or newer tuple */
......@@ -75,7 +84,7 @@ typedef struct HeapTupleHeaderData
uint8 t_hoff; /* sizeof header incl. bitmap, padding */
/* ^ - 31 bytes - ^ */
/* ^ - 27 bytes - ^ */
bits8 t_bits[1]; /* bitmap of NULLs -- VARIABLE LENGTH */
......@@ -96,6 +105,8 @@ typedef HeapTupleHeaderData *HeapTupleHeader;
* attribute(s) */
#define HEAP_HASEXTENDED 0x000C /* the two above combined */
#define HEAP_XMIN_IS_XMAX 0x0040 /* created and deleted in the */
/* same transaction */
#define HEAP_XMAX_UNLOGGED 0x0080 /* to lock tuple for update */
/* without logging */
#define HEAP_XMIN_COMMITTED 0x0100 /* t_xmin committed */
......@@ -108,6 +119,7 @@ typedef HeapTupleHeaderData *HeapTupleHeader;
* vacuum */
#define HEAP_MOVED_IN 0x8000 /* moved from another place by
* vacuum */
#define HEAP_MOVED (HEAP_MOVED_OFF | HEAP_MOVED_IN)
#define HEAP_XACT_MASK 0xFFF0 /* visibility-related bits */
......@@ -116,53 +128,100 @@ typedef HeapTupleHeaderData *HeapTupleHeader;
/* HeapTupleHeader accessor macros */
#define HeapTupleHeaderGetXmin(tup) \
((tup)->t_xmin)
( \
(tup)->t_xmin \
)
#define HeapTupleHeaderGetXmax(tup) \
((tup)->t_xmax)
( \
((tup)->t_infomask & HEAP_XMIN_IS_XMAX) ? \
(tup)->t_xmin \
: \
(tup)->t_xmax \
)
/* no AssertMacro, because this is read as a system-defined attribute also */
/* no AssertMacro, because this is read as a system-defined attribute */
#define HeapTupleHeaderGetCmin(tup) \
( \
(tup)->t_cmin \
((tup)->t_infomask & HEAP_MOVED) ? \
FirstCommandId \
: \
( \
((tup)->t_infomask & (HEAP_XMIN_IS_XMAX | HEAP_XMAX_INVALID)) ? \
(CommandId) (tup)->t_cid \
: \
FirstCommandId \
) \
)
#define HeapTupleHeaderGetCmax(tup) \
((tup)->t_cmax)
( \
((tup)->t_infomask & HEAP_MOVED) ? \
FirstCommandId \
: \
( \
((tup)->t_infomask & (HEAP_XMIN_IS_XMAX | HEAP_XMAX_INVALID)) ? \
(CommandId) (tup)->t_xmax \
: \
(CommandId) (tup)->t_cid \
) \
)
#define HeapTupleHeaderGetXvac(tup) \
( \
AssertMacro((tup)->t_infomask & (HEAP_MOVED_IN | HEAP_MOVED_OFF)), \
(TransactionId) (tup)->t_cmin \
AssertMacro((tup)->t_infomask & HEAP_MOVED), \
(tup)->t_cid \
)
#define HeapTupleHeaderSetXmin(tup, xid) \
(TransactionIdStore((xid), &(tup)->t_xmin))
( \
TransactionIdStore((xid), &(tup)->t_xmin) \
)
#define HeapTupleHeaderSetXminInvalid(tup) \
(StoreInvalidTransactionId(&(tup)->t_xmin))
do { \
(tup)->t_infomask &= ~HEAP_XMIN_IS_XMAX; \
StoreInvalidTransactionId(&(tup)->t_xmin); \
} while (0)
#define HeapTupleHeaderSetXmax(tup, xid) \
(TransactionIdStore((xid), &(tup)->t_xmax))
do { \
if (TransactionIdEquals((tup)->t_xmin, (xid))) \
(tup)->t_infomask |= HEAP_XMIN_IS_XMAX; \
else \
{ \
(tup)->t_infomask &= ~HEAP_XMIN_IS_XMAX; \
TransactionIdStore((xid), &(tup)->t_xmax); \
} \
} while (0)
#define HeapTupleHeaderSetXmaxInvalid(tup) \
(StoreInvalidTransactionId(&(tup)->t_xmax))
do { \
(tup)->t_infomask &= ~HEAP_XMIN_IS_XMAX; \
StoreInvalidTransactionId(&(tup)->t_xmax); \
} while (0)
#define HeapTupleHeaderSetCmin(tup, cid) \
( \
AssertMacro(!((tup)->t_infomask & (HEAP_MOVED_IN | HEAP_MOVED_OFF))), \
(tup)->t_cmin = (cid) \
)
do { \
Assert(!((tup)->t_infomask & HEAP_MOVED)); \
TransactionIdStore((TransactionId) (cid), &(tup)->t_cid); \
} while (0)
#define HeapTupleHeaderSetCmax(tup, cid) \
((tup)->t_cmax = (cid))
do { \
Assert(!((tup)->t_infomask & HEAP_MOVED)); \
if ((tup)->t_infomask & HEAP_XMIN_IS_XMAX) \
TransactionIdStore((TransactionId) (cid), &(tup)->t_xmax); \
else \
TransactionIdStore((TransactionId) (cid), &(tup)->t_cid); \
} while (0)
#define HeapTupleHeaderSetXvac(tup, xid) \
( \
AssertMacro((tup)->t_infomask & (HEAP_MOVED_IN | HEAP_MOVED_OFF)), \
TransactionIdStore((xid), (TransactionId *) &((tup)->t_cmin)) \
)
do { \
Assert((tup)->t_infomask & HEAP_MOVED); \
TransactionIdStore((xid), &(tup)->t_cid); \
} while (0)
/*
......
src/include/catalog/catversion.h
View file @ 97bfffe5
......@@ -37,7 +37,7 @@
* Portions Copyright (c) 1996-2002, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $Id: catversion.h,v 1.136 2002/06/20 20:29:43 momjian Exp $
* $Id: catversion.h,v 1.137 2002/07/02 05:46:14 momjian Exp $
*
*-------------------------------------------------------------------------
*/
......@@ -53,6 +53,6 @@
*/
/* yyyymmddN */
#define CATALOG_VERSION_NO 200206151
#define CATALOG_VERSION_NO 200207021
#endif
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