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heapam_xlog.h
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1 /*-------------------------------------------------------------------------
2  *
3  * heapam_xlog.h
4  * POSTGRES heap access XLOG definitions.
5  *
6  *
7  * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
8  * Portions Copyright (c) 1994, Regents of the University of California
9  *
10  * src/include/access/heapam_xlog.h
11  *
12  *-------------------------------------------------------------------------
13  */
14 #ifndef HEAPAM_XLOG_H
15 #define HEAPAM_XLOG_H
16 
17 #include "access/htup.h"
18 #include "access/xlogreader.h"
19 #include "lib/stringinfo.h"
20 #include "storage/buf.h"
21 #include "storage/bufpage.h"
22 #include "storage/relfilenode.h"
23 #include "utils/relcache.h"
24 
25 
26 /*
27  * WAL record definitions for heapam.c's WAL operations
28  *
29  * XLOG allows to store some information in high 4 bits of log
30  * record xl_info field. We use 3 for opcode and one for init bit.
31  */
32 #define XLOG_HEAP_INSERT 0x00
33 #define XLOG_HEAP_DELETE 0x10
34 #define XLOG_HEAP_UPDATE 0x20
35 /* 0x030 is free, was XLOG_HEAP_MOVE */
36 #define XLOG_HEAP_HOT_UPDATE 0x40
37 #define XLOG_HEAP_CONFIRM 0x50
38 #define XLOG_HEAP_LOCK 0x60
39 #define XLOG_HEAP_INPLACE 0x70
40 
41 #define XLOG_HEAP_OPMASK 0x70
42 /*
43  * When we insert 1st item on new page in INSERT, UPDATE, HOT_UPDATE,
44  * or MULTI_INSERT, we can (and we do) restore entire page in redo
45  */
46 #define XLOG_HEAP_INIT_PAGE 0x80
47 /*
48  * We ran out of opcodes, so heapam.c now has a second RmgrId. These opcodes
49  * are associated with RM_HEAP2_ID, but are not logically different from
50  * the ones above associated with RM_HEAP_ID. XLOG_HEAP_OPMASK applies to
51  * these, too.
52  */
53 #define XLOG_HEAP2_REWRITE 0x00
54 #define XLOG_HEAP2_CLEAN 0x10
55 #define XLOG_HEAP2_FREEZE_PAGE 0x20
56 #define XLOG_HEAP2_CLEANUP_INFO 0x30
57 #define XLOG_HEAP2_VISIBLE 0x40
58 #define XLOG_HEAP2_MULTI_INSERT 0x50
59 #define XLOG_HEAP2_LOCK_UPDATED 0x60
60 #define XLOG_HEAP2_NEW_CID 0x70
61 
62 /*
63  * xl_heap_insert/xl_heap_multi_insert flag values, 8 bits are available.
64  */
65 /* PD_ALL_VISIBLE was cleared */
66 #define XLH_INSERT_ALL_VISIBLE_CLEARED (1<<0)
67 #define XLH_INSERT_LAST_IN_MULTI (1<<1)
68 #define XLH_INSERT_IS_SPECULATIVE (1<<2)
69 #define XLH_INSERT_CONTAINS_NEW_TUPLE (1<<3)
70 
71 /*
72  * xl_heap_update flag values, 8 bits are available.
73  */
74 /* PD_ALL_VISIBLE was cleared */
75 #define XLH_UPDATE_OLD_ALL_VISIBLE_CLEARED (1<<0)
76 /* PD_ALL_VISIBLE was cleared in the 2nd page */
77 #define XLH_UPDATE_NEW_ALL_VISIBLE_CLEARED (1<<1)
78 #define XLH_UPDATE_CONTAINS_OLD_TUPLE (1<<2)
79 #define XLH_UPDATE_CONTAINS_OLD_KEY (1<<3)
80 #define XLH_UPDATE_CONTAINS_NEW_TUPLE (1<<4)
81 #define XLH_UPDATE_PREFIX_FROM_OLD (1<<5)
82 #define XLH_UPDATE_SUFFIX_FROM_OLD (1<<6)
83 
84 /* convenience macro for checking whether any form of old tuple was logged */
85 #define XLH_UPDATE_CONTAINS_OLD \
86  (XLH_UPDATE_CONTAINS_OLD_TUPLE | XLH_UPDATE_CONTAINS_OLD_KEY)
87 
88 /*
89  * xl_heap_delete flag values, 8 bits are available.
90  */
91 /* PD_ALL_VISIBLE was cleared */
92 #define XLH_DELETE_ALL_VISIBLE_CLEARED (1<<0)
93 #define XLH_DELETE_CONTAINS_OLD_TUPLE (1<<1)
94 #define XLH_DELETE_CONTAINS_OLD_KEY (1<<2)
95 #define XLH_DELETE_IS_SUPER (1<<3)
96 
97 /* convenience macro for checking whether any form of old tuple was logged */
98 #define XLH_DELETE_CONTAINS_OLD \
99  (XLH_DELETE_CONTAINS_OLD_TUPLE | XLH_DELETE_CONTAINS_OLD_KEY)
100 
101 /* This is what we need to know about delete */
102 typedef struct xl_heap_delete
103 {
104  TransactionId xmax; /* xmax of the deleted tuple */
105  OffsetNumber offnum; /* deleted tuple's offset */
106  uint8 infobits_set; /* infomask bits */
109 
110 #define SizeOfHeapDelete (offsetof(xl_heap_delete, flags) + sizeof(uint8))
111 
112 /*
113  * We don't store the whole fixed part (HeapTupleHeaderData) of an inserted
114  * or updated tuple in WAL; we can save a few bytes by reconstructing the
115  * fields that are available elsewhere in the WAL record, or perhaps just
116  * plain needn't be reconstructed. These are the fields we must store.
117  * NOTE: t_hoff could be recomputed, but we may as well store it because
118  * it will come for free due to alignment considerations.
119  */
120 typedef struct xl_heap_header
121 {
126 
127 #define SizeOfHeapHeader (offsetof(xl_heap_header, t_hoff) + sizeof(uint8))
128 
129 /* This is what we need to know about insert */
130 typedef struct xl_heap_insert
131 {
132  OffsetNumber offnum; /* inserted tuple's offset */
134 
135  /* xl_heap_header & TUPLE DATA in backup block 0 */
137 
138 #define SizeOfHeapInsert (offsetof(xl_heap_insert, flags) + sizeof(uint8))
139 
140 /*
141  * This is what we need to know about a multi-insert.
142  *
143  * The main data of the record consists of this xl_heap_multi_insert header.
144  * 'offsets' array is omitted if the whole page is reinitialized
145  * (XLOG_HEAP_INIT_PAGE).
146  *
147  * In block 0's data portion, there is an xl_multi_insert_tuple struct,
148  * followed by the tuple data for each tuple. There is padding to align
149  * each xl_multi_insert struct.
150  */
151 typedef struct xl_heap_multi_insert
152 {
155  OffsetNumber offsets[FLEXIBLE_ARRAY_MEMBER];
157 
158 #define SizeOfHeapMultiInsert offsetof(xl_heap_multi_insert, offsets)
159 
160 typedef struct xl_multi_insert_tuple
161 {
162  uint16 datalen; /* size of tuple data that follows */
166  /* TUPLE DATA FOLLOWS AT END OF STRUCT */
168 
169 #define SizeOfMultiInsertTuple (offsetof(xl_multi_insert_tuple, t_hoff) + sizeof(uint8))
170 
171 /*
172  * This is what we need to know about update|hot_update
173  *
174  * Backup blk 0: new page
175  *
176  * If XLOG_HEAP_PREFIX_FROM_OLD or XLOG_HEAP_SUFFIX_FROM_OLD flags are set,
177  * the prefix and/or suffix come first, as one or two uint16s.
178  *
179  * After that, xl_heap_header and new tuple data follow. The new tuple
180  * data doesn't include the prefix and suffix, which are copied from the
181  * old tuple on replay.
182  *
183  * If HEAP_CONTAINS_NEW_TUPLE_DATA flag is given, the tuple data is
184  * included even if a full-page image was taken.
185  *
186  * Backup blk 1: old page, if different. (no data, just a reference to the blk)
187  */
188 typedef struct xl_heap_update
189 {
190  TransactionId old_xmax; /* xmax of the old tuple */
191  OffsetNumber old_offnum; /* old tuple's offset */
192  uint8 old_infobits_set; /* infomask bits to set on old tuple */
194  TransactionId new_xmax; /* xmax of the new tuple */
195  OffsetNumber new_offnum; /* new tuple's offset */
196 
197  /*
198  * If XLOG_HEAP_CONTAINS_OLD_TUPLE or XLOG_HEAP_CONTAINS_OLD_KEY flags are
199  * set, a xl_heap_header struct and tuple data for the old tuple follows.
200  */
202 
203 #define SizeOfHeapUpdate (offsetof(xl_heap_update, new_offnum) + sizeof(OffsetNumber))
204 
205 /*
206  * This is what we need to know about vacuum page cleanup/redirect
207  *
208  * The array of OffsetNumbers following the fixed part of the record contains:
209  * * for each redirected item: the item offset, then the offset redirected to
210  * * for each now-dead item: the item offset
211  * * for each now-unused item: the item offset
212  * The total number of OffsetNumbers is therefore 2*nredirected+ndead+nunused.
213  * Note that nunused is not explicitly stored, but may be found by reference
214  * to the total record length.
215  */
216 typedef struct xl_heap_clean
217 {
221  /* OFFSET NUMBERS are in the block reference 0 */
222 } xl_heap_clean;
223 
224 #define SizeOfHeapClean (offsetof(xl_heap_clean, ndead) + sizeof(uint16))
225 
226 /*
227  * Cleanup_info is required in some cases during a lazy VACUUM.
228  * Used for reporting the results of HeapTupleHeaderAdvanceLatestRemovedXid()
229  * see vacuumlazy.c for full explanation
230  */
231 typedef struct xl_heap_cleanup_info
232 {
236 
237 #define SizeOfHeapCleanupInfo (sizeof(xl_heap_cleanup_info))
238 
239 /* flags for infobits_set */
240 #define XLHL_XMAX_IS_MULTI 0x01
241 #define XLHL_XMAX_LOCK_ONLY 0x02
242 #define XLHL_XMAX_EXCL_LOCK 0x04
243 #define XLHL_XMAX_KEYSHR_LOCK 0x08
244 #define XLHL_KEYS_UPDATED 0x10
245 
246 /* flag bits for xl_heap_lock / xl_heap_lock_updated's flag field */
247 #define XLH_LOCK_ALL_FROZEN_CLEARED 0x01
248 
249 /* This is what we need to know about lock */
250 typedef struct xl_heap_lock
251 {
252  TransactionId locking_xid; /* might be a MultiXactId not xid */
253  OffsetNumber offnum; /* locked tuple's offset on page */
254  int8 infobits_set; /* infomask and infomask2 bits to set */
255  uint8 flags; /* XLH_LOCK_* flag bits */
256 } xl_heap_lock;
257 
258 #define SizeOfHeapLock (offsetof(xl_heap_lock, flags) + sizeof(int8))
259 
260 /* This is what we need to know about locking an updated version of a row */
261 typedef struct xl_heap_lock_updated
262 {
268 
269 #define SizeOfHeapLockUpdated (offsetof(xl_heap_lock_updated, flags) + sizeof(uint8))
270 
271 /* This is what we need to know about confirmation of speculative insertion */
272 typedef struct xl_heap_confirm
273 {
274  OffsetNumber offnum; /* confirmed tuple's offset on page */
276 
277 #define SizeOfHeapConfirm (offsetof(xl_heap_confirm, offnum) + sizeof(OffsetNumber))
278 
279 /* This is what we need to know about in-place update */
280 typedef struct xl_heap_inplace
281 {
282  OffsetNumber offnum; /* updated tuple's offset on page */
283  /* TUPLE DATA FOLLOWS AT END OF STRUCT */
285 
286 #define SizeOfHeapInplace (offsetof(xl_heap_inplace, offnum) + sizeof(OffsetNumber))
287 
288 /*
289  * This struct represents a 'freeze plan', which is what we need to know about
290  * a single tuple being frozen during vacuum.
291  */
292 /* 0x01 was XLH_FREEZE_XMIN */
293 #define XLH_FREEZE_XVAC 0x02
294 #define XLH_INVALID_XVAC 0x04
295 
296 typedef struct xl_heap_freeze_tuple
297 {
304 
305 /*
306  * This is what we need to know about a block being frozen during vacuum
307  *
308  * Backup block 0's data contains an array of xl_heap_freeze_tuple structs,
309  * one for each tuple.
310  */
311 typedef struct xl_heap_freeze_page
312 {
316 
317 #define SizeOfHeapFreezePage (offsetof(xl_heap_freeze_page, ntuples) + sizeof(uint16))
318 
319 /*
320  * This is what we need to know about setting a visibility map bit
321  *
322  * Backup blk 0: visibility map buffer
323  * Backup blk 1: heap buffer
324  */
325 typedef struct xl_heap_visible
326 {
330 
331 #define SizeOfHeapVisible (offsetof(xl_heap_visible, flags) + sizeof(uint8))
332 
333 typedef struct xl_heap_new_cid
334 {
335  /*
336  * store toplevel xid so we don't have to merge cids from different
337  * transactions
338  */
342 
343  /*
344  * don't really need the combocid since we have the actual values right in
345  * this struct, but the padding makes it free and its useful for
346  * debugging.
347  */
349 
350  /*
351  * Store the relfilenode/ctid pair to facilitate lookups.
352  */
356 
357 #define SizeOfHeapNewCid (offsetof(xl_heap_new_cid, target_tid) + sizeof(ItemPointerData))
358 
359 /* logical rewrite xlog record header */
361 {
362  TransactionId mapped_xid; /* xid that might need to see the row */
363  Oid mapped_db; /* DbOid or InvalidOid for shared rels */
364  Oid mapped_rel; /* Oid of the mapped relation */
365  off_t offset; /* How far have we written so far */
366  uint32 num_mappings; /* Number of in-memory mappings */
367  XLogRecPtr start_lsn; /* Insert LSN at begin of rewrite */
369 
371  TransactionId *latestRemovedXid);
372 
373 extern void heap_redo(XLogReaderState *record);
374 extern void heap_desc(StringInfo buf, XLogReaderState *record);
375 extern const char *heap_identify(uint8 info);
376 extern void heap_mask(char *pagedata, BlockNumber blkno);
377 extern void heap2_redo(XLogReaderState *record);
378 extern void heap2_desc(StringInfo buf, XLogReaderState *record);
379 extern const char *heap2_identify(uint8 info);
381 
383  TransactionId latestRemovedXid);
384 extern XLogRecPtr log_heap_clean(Relation reln, Buffer buffer,
385  OffsetNumber *redirected, int nredirected,
386  OffsetNumber *nowdead, int ndead,
387  OffsetNumber *nowunused, int nunused,
388  TransactionId latestRemovedXid);
389 extern XLogRecPtr log_heap_freeze(Relation reln, Buffer buffer,
390  TransactionId cutoff_xid, xl_heap_freeze_tuple *tuples,
391  int ntuples);
393  TransactionId cutoff_xid,
394  TransactionId cutoff_multi,
396  bool *totally_frozen);
398  xl_heap_freeze_tuple *xlrec_tp);
399 extern XLogRecPtr log_heap_visible(RelFileNode rnode, Buffer heap_buffer,
400  Buffer vm_buffer, TransactionId cutoff_xid, uint8 flags);
401 
402 #endif /* HEAPAM_XLOG_H */
uint32 CommandId
Definition: c.h:411
struct xl_heap_freeze_page xl_heap_freeze_page
uint8 old_infobits_set
Definition: heapam_xlog.h:192
OffsetNumber offnum
Definition: heapam_xlog.h:274
OffsetNumber offnum
Definition: heapam_xlog.h:253
OffsetNumber offset
Definition: heapam_xlog.h:299
XLogRecPtr log_heap_clean(Relation reln, Buffer buffer, OffsetNumber *redirected, int nredirected, OffsetNumber *nowdead, int ndead, OffsetNumber *nowunused, int nunused, TransactionId latestRemovedXid)
Definition: heapam.c:7402
TransactionId locking_xid
Definition: heapam_xlog.h:252
uint32 TransactionId
Definition: c.h:397
void heap_xlog_logical_rewrite(XLogReaderState *r)
Definition: rewriteheap.c:1118
uint16 nredirected
Definition: heapam_xlog.h:219
OffsetNumber offsets[FLEXIBLE_ARRAY_MEMBER]
Definition: heapam_xlog.h:155
CommandId combocid
Definition: heapam_xlog.h:348
struct xl_heap_multi_insert xl_heap_multi_insert
TransactionId cutoff_xid
Definition: heapam_xlog.h:313
void heap_desc(StringInfo buf, XLogReaderState *record)
Definition: heapdesc.c:35
struct xl_heap_insert xl_heap_insert
unsigned char uint8
Definition: c.h:266
struct xl_multi_insert_tuple xl_multi_insert_tuple
uint16 t_infomask2
Definition: heapam_xlog.h:122
CommandId cmax
Definition: heapam_xlog.h:341
ItemPointerData target_tid
Definition: heapam_xlog.h:354
uint32 BlockNumber
Definition: block.h:31
OffsetNumber old_offnum
Definition: heapam_xlog.h:191
unsigned int Oid
Definition: postgres_ext.h:31
OffsetNumber offnum
Definition: heapam_xlog.h:264
struct xl_heap_lock xl_heap_lock
struct xl_heap_confirm xl_heap_confirm
struct xl_heap_inplace xl_heap_inplace
OffsetNumber offnum
Definition: heapam_xlog.h:105
struct xl_heap_rewrite_mapping xl_heap_rewrite_mapping
uint16 OffsetNumber
Definition: off.h:24
unsigned short uint16
Definition: c.h:267
bool heap_prepare_freeze_tuple(HeapTupleHeader tuple, TransactionId cutoff_xid, TransactionId cutoff_multi, xl_heap_freeze_tuple *frz, bool *totally_frozen)
Definition: heapam.c:6624
struct xl_heap_cleanup_info xl_heap_cleanup_info
XLogRecPtr log_heap_visible(RelFileNode rnode, Buffer heap_buffer, Buffer vm_buffer, TransactionId cutoff_xid, uint8 flags)
Definition: heapam.c:7494
TransactionId new_xmax
Definition: heapam_xlog.h:194
int8 infobits_set
Definition: heapam_xlog.h:254
TransactionId cutoff_xid
Definition: heapam_xlog.h:327
TransactionId xmax
Definition: heapam_xlog.h:104
XLogRecPtr log_heap_cleanup_info(RelFileNode rnode, TransactionId latestRemovedXid)
Definition: heapam.c:7373
static char * buf
Definition: pg_test_fsync.c:65
struct xl_heap_freeze_tuple xl_heap_freeze_tuple
struct xl_heap_delete xl_heap_delete
void heap2_redo(XLogReaderState *record)
Definition: heapam.c:9084
unsigned int uint32
Definition: c.h:268
TransactionId xmax
Definition: heapam_xlog.h:263
signed char int8
Definition: c.h:254
RelFileNode target_node
Definition: heapam_xlog.h:353
struct xl_heap_lock_updated xl_heap_lock_updated
struct xl_heap_header xl_heap_header
struct xl_heap_visible xl_heap_visible
OffsetNumber offnum
Definition: heapam_xlog.h:282
void HeapTupleHeaderAdvanceLatestRemovedXid(HeapTupleHeader tuple, TransactionId *latestRemovedXid)
Definition: heapam.c:7334
struct xl_heap_new_cid xl_heap_new_cid
void heap_redo(XLogReaderState *record)
Definition: heapam.c:9046
TransactionId mapped_xid
Definition: heapam_xlog.h:362
void heap_execute_freeze_tuple(HeapTupleHeader tuple, xl_heap_freeze_tuple *xlrec_tp)
Definition: heapam.c:6802
void heap2_desc(StringInfo buf, XLogReaderState *record)
Definition: heapdesc.c:100
uint64 XLogRecPtr
Definition: xlogdefs.h:21
uint8 infobits_set
Definition: heapam_xlog.h:106
const char * heap_identify(uint8 info)
Definition: heapdesc.c:162
uint16 t_infomask
Definition: heapam_xlog.h:123
const char * heap2_identify(uint8 info)
Definition: heapdesc.c:204
TransactionId latestRemovedXid
Definition: heapam_xlog.h:218
void heap_mask(char *pagedata, BlockNumber blkno)
Definition: heapam.c:9167
TransactionId xmax
Definition: heapam_xlog.h:298
struct xl_heap_update xl_heap_update
CommandId cmin
Definition: heapam_xlog.h:340
OffsetNumber new_offnum
Definition: heapam_xlog.h:195
int Buffer
Definition: buf.h:23
TransactionId latestRemovedXid
Definition: heapam_xlog.h:234
OffsetNumber offnum
Definition: heapam_xlog.h:132
XLogRecPtr log_heap_freeze(Relation reln, Buffer buffer, TransactionId cutoff_xid, xl_heap_freeze_tuple *tuples, int ntuples)
Definition: heapam.c:7453
TransactionId old_xmax
Definition: heapam_xlog.h:190
struct xl_heap_clean xl_heap_clean
TransactionId top_xid
Definition: heapam_xlog.h:339