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xloginsert.c
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1 /*-------------------------------------------------------------------------
2  *
3  * xloginsert.c
4  * Functions for constructing WAL records
5  *
6  * Constructing a WAL record begins with a call to XLogBeginInsert,
7  * followed by a number of XLogRegister* calls. The registered data is
8  * collected in private working memory, and finally assembled into a chain
9  * of XLogRecData structs by a call to XLogRecordAssemble(). See
10  * access/transam/README for details.
11  *
12  * Portions Copyright (c) 1996-2024, PostgreSQL Global Development Group
13  * Portions Copyright (c) 1994, Regents of the University of California
14  *
15  * src/backend/access/transam/xloginsert.c
16  *
17  *-------------------------------------------------------------------------
18  */
19 
20 #include "postgres.h"
21 
22 #ifdef USE_LZ4
23 #include <lz4.h>
24 #endif
25 
26 #ifdef USE_ZSTD
27 #include <zstd.h>
28 #endif
29 
30 #include "access/xact.h"
31 #include "access/xlog.h"
32 #include "access/xlog_internal.h"
33 #include "access/xloginsert.h"
34 #include "catalog/pg_control.h"
35 #include "common/pg_lzcompress.h"
36 #include "miscadmin.h"
37 #include "pg_trace.h"
38 #include "replication/origin.h"
39 #include "storage/bufmgr.h"
40 #include "storage/proc.h"
41 #include "utils/memutils.h"
42 
43 /*
44  * Guess the maximum buffer size required to store a compressed version of
45  * backup block image.
46  */
47 #ifdef USE_LZ4
48 #define LZ4_MAX_BLCKSZ LZ4_COMPRESSBOUND(BLCKSZ)
49 #else
50 #define LZ4_MAX_BLCKSZ 0
51 #endif
52 
53 #ifdef USE_ZSTD
54 #define ZSTD_MAX_BLCKSZ ZSTD_COMPRESSBOUND(BLCKSZ)
55 #else
56 #define ZSTD_MAX_BLCKSZ 0
57 #endif
58 
59 #define PGLZ_MAX_BLCKSZ PGLZ_MAX_OUTPUT(BLCKSZ)
60 
61 /* Buffer size required to store a compressed version of backup block image */
62 #define COMPRESS_BUFSIZE Max(Max(PGLZ_MAX_BLCKSZ, LZ4_MAX_BLCKSZ), ZSTD_MAX_BLCKSZ)
63 
64 /*
65  * For each block reference registered with XLogRegisterBuffer, we fill in
66  * a registered_buffer struct.
67  */
68 typedef struct
69 {
70  bool in_use; /* is this slot in use? */
71  uint8 flags; /* REGBUF_* flags */
72  RelFileLocator rlocator; /* identifies the relation and block */
75  Page page; /* page content */
76  uint32 rdata_len; /* total length of data in rdata chain */
77  XLogRecData *rdata_head; /* head of the chain of data registered with
78  * this block */
79  XLogRecData *rdata_tail; /* last entry in the chain, or &rdata_head if
80  * empty */
81 
82  XLogRecData bkp_rdatas[2]; /* temporary rdatas used to hold references to
83  * backup block data in XLogRecordAssemble() */
84 
85  /* buffer to store a compressed version of backup block image */
86  char compressed_page[COMPRESS_BUFSIZE];
88 
90 static int max_registered_buffers; /* allocated size */
91 static int max_registered_block_id = 0; /* highest block_id + 1 currently
92  * registered */
93 
94 /*
95  * A chain of XLogRecDatas to hold the "main data" of a WAL record, registered
96  * with XLogRegisterData(...).
97  */
100 static uint64 mainrdata_len; /* total # of bytes in chain */
101 
102 /* flags for the in-progress insertion */
104 
105 /*
106  * These are used to hold the record header while constructing a record.
107  * 'hdr_scratch' is not a plain variable, but is palloc'd at initialization,
108  * because we want it to be MAXALIGNed and padding bytes zeroed.
109  *
110  * For simplicity, it's allocated large enough to hold the headers for any
111  * WAL record.
112  */
114 static char *hdr_scratch = NULL;
115 
116 #define SizeOfXlogOrigin (sizeof(RepOriginId) + sizeof(char))
117 #define SizeOfXLogTransactionId (sizeof(TransactionId) + sizeof(char))
118 
119 #define HEADER_SCRATCH_SIZE \
120  (SizeOfXLogRecord + \
121  MaxSizeOfXLogRecordBlockHeader * (XLR_MAX_BLOCK_ID + 1) + \
122  SizeOfXLogRecordDataHeaderLong + SizeOfXlogOrigin + \
123  SizeOfXLogTransactionId)
124 
125 /*
126  * An array of XLogRecData structs, to hold registered data.
127  */
129 static int num_rdatas; /* entries currently used */
130 static int max_rdatas; /* allocated size */
131 
132 static bool begininsert_called = false;
133 
134 /* Memory context to hold the registered buffer and data references. */
136 
137 static XLogRecData *XLogRecordAssemble(RmgrId rmid, uint8 info,
139  XLogRecPtr *fpw_lsn, int *num_fpi,
140  bool *topxid_included);
141 static bool XLogCompressBackupBlock(char *page, uint16 hole_offset,
142  uint16 hole_length, char *dest, uint16 *dlen);
143 
144 /*
145  * Begin constructing a WAL record. This must be called before the
146  * XLogRegister* functions and XLogInsert().
147  */
148 void
150 {
153  Assert(mainrdata_len == 0);
154 
155  /* cross-check on whether we should be here or not */
156  if (!XLogInsertAllowed())
157  elog(ERROR, "cannot make new WAL entries during recovery");
158 
159  if (begininsert_called)
160  elog(ERROR, "XLogBeginInsert was already called");
161 
162  begininsert_called = true;
163 }
164 
165 /*
166  * Ensure that there are enough buffer and data slots in the working area,
167  * for subsequent XLogRegisterBuffer, XLogRegisterData and XLogRegisterBufData
168  * calls.
169  *
170  * There is always space for a small number of buffers and data chunks, enough
171  * for most record types. This function is for the exceptional cases that need
172  * more.
173  */
174 void
175 XLogEnsureRecordSpace(int max_block_id, int ndatas)
176 {
177  int nbuffers;
178 
179  /*
180  * This must be called before entering a critical section, because
181  * allocating memory inside a critical section can fail. repalloc() will
182  * check the same, but better to check it here too so that we fail
183  * consistently even if the arrays happen to be large enough already.
184  */
185  Assert(CritSectionCount == 0);
186 
187  /* the minimum values can't be decreased */
188  if (max_block_id < XLR_NORMAL_MAX_BLOCK_ID)
189  max_block_id = XLR_NORMAL_MAX_BLOCK_ID;
190  if (ndatas < XLR_NORMAL_RDATAS)
191  ndatas = XLR_NORMAL_RDATAS;
192 
193  if (max_block_id > XLR_MAX_BLOCK_ID)
194  elog(ERROR, "maximum number of WAL record block references exceeded");
195  nbuffers = max_block_id + 1;
196 
197  if (nbuffers > max_registered_buffers)
198  {
200  repalloc(registered_buffers, sizeof(registered_buffer) * nbuffers);
201 
202  /*
203  * At least the padding bytes in the structs must be zeroed, because
204  * they are included in WAL data, but initialize it all for tidiness.
205  */
207  (nbuffers - max_registered_buffers) * sizeof(registered_buffer));
208  max_registered_buffers = nbuffers;
209  }
210 
211  if (ndatas > max_rdatas)
212  {
213  rdatas = (XLogRecData *) repalloc(rdatas, sizeof(XLogRecData) * ndatas);
214  max_rdatas = ndatas;
215  }
216 }
217 
218 /*
219  * Reset WAL record construction buffers.
220  */
221 void
223 {
224  int i;
225 
226  for (i = 0; i < max_registered_block_id; i++)
227  registered_buffers[i].in_use = false;
228 
229  num_rdatas = 0;
231  mainrdata_len = 0;
233  curinsert_flags = 0;
234  begininsert_called = false;
235 }
236 
237 /*
238  * Register a reference to a buffer with the WAL record being constructed.
239  * This must be called for every page that the WAL-logged operation modifies.
240  */
241 void
242 XLogRegisterBuffer(uint8 block_id, Buffer buffer, uint8 flags)
243 {
244  registered_buffer *regbuf;
245 
246  /* NO_IMAGE doesn't make sense with FORCE_IMAGE */
247  Assert(!((flags & REGBUF_FORCE_IMAGE) && (flags & (REGBUF_NO_IMAGE))));
249 
250  /*
251  * Ordinarily, buffer should be exclusive-locked and marked dirty before
252  * we get here, otherwise we could end up violating one of the rules in
253  * access/transam/README.
254  *
255  * Some callers intentionally register a clean page and never update that
256  * page's LSN; in that case they can pass the flag REGBUF_NO_CHANGE to
257  * bypass these checks.
258  */
259 #ifdef USE_ASSERT_CHECKING
260  if (!(flags & REGBUF_NO_CHANGE))
261  Assert(BufferIsExclusiveLocked(buffer) && BufferIsDirty(buffer));
262 #endif
263 
264  if (block_id >= max_registered_block_id)
265  {
266  if (block_id >= max_registered_buffers)
267  elog(ERROR, "too many registered buffers");
268  max_registered_block_id = block_id + 1;
269  }
270 
271  regbuf = &registered_buffers[block_id];
272 
273  BufferGetTag(buffer, &regbuf->rlocator, &regbuf->forkno, &regbuf->block);
274  regbuf->page = BufferGetPage(buffer);
275  regbuf->flags = flags;
276  regbuf->rdata_tail = (XLogRecData *) &regbuf->rdata_head;
277  regbuf->rdata_len = 0;
278 
279  /*
280  * Check that this page hasn't already been registered with some other
281  * block_id.
282  */
283 #ifdef USE_ASSERT_CHECKING
284  {
285  int i;
286 
287  for (i = 0; i < max_registered_block_id; i++)
288  {
289  registered_buffer *regbuf_old = &registered_buffers[i];
290 
291  if (i == block_id || !regbuf_old->in_use)
292  continue;
293 
294  Assert(!RelFileLocatorEquals(regbuf_old->rlocator, regbuf->rlocator) ||
295  regbuf_old->forkno != regbuf->forkno ||
296  regbuf_old->block != regbuf->block);
297  }
298  }
299 #endif
300 
301  regbuf->in_use = true;
302 }
303 
304 /*
305  * Like XLogRegisterBuffer, but for registering a block that's not in the
306  * shared buffer pool (i.e. when you don't have a Buffer for it).
307  */
308 void
309 XLogRegisterBlock(uint8 block_id, RelFileLocator *rlocator, ForkNumber forknum,
310  BlockNumber blknum, Page page, uint8 flags)
311 {
312  registered_buffer *regbuf;
313 
315 
316  if (block_id >= max_registered_block_id)
317  max_registered_block_id = block_id + 1;
318 
319  if (block_id >= max_registered_buffers)
320  elog(ERROR, "too many registered buffers");
321 
322  regbuf = &registered_buffers[block_id];
323 
324  regbuf->rlocator = *rlocator;
325  regbuf->forkno = forknum;
326  regbuf->block = blknum;
327  regbuf->page = page;
328  regbuf->flags = flags;
329  regbuf->rdata_tail = (XLogRecData *) &regbuf->rdata_head;
330  regbuf->rdata_len = 0;
331 
332  /*
333  * Check that this page hasn't already been registered with some other
334  * block_id.
335  */
336 #ifdef USE_ASSERT_CHECKING
337  {
338  int i;
339 
340  for (i = 0; i < max_registered_block_id; i++)
341  {
342  registered_buffer *regbuf_old = &registered_buffers[i];
343 
344  if (i == block_id || !regbuf_old->in_use)
345  continue;
346 
347  Assert(!RelFileLocatorEquals(regbuf_old->rlocator, regbuf->rlocator) ||
348  regbuf_old->forkno != regbuf->forkno ||
349  regbuf_old->block != regbuf->block);
350  }
351  }
352 #endif
353 
354  regbuf->in_use = true;
355 }
356 
357 /*
358  * Add data to the WAL record that's being constructed.
359  *
360  * The data is appended to the "main chunk", available at replay with
361  * XLogRecGetData().
362  */
363 void
365 {
366  XLogRecData *rdata;
367 
369 
370  if (num_rdatas >= max_rdatas)
371  ereport(ERROR,
372  (errmsg_internal("too much WAL data"),
373  errdetail_internal("%d out of %d data segments are already in use.",
375  rdata = &rdatas[num_rdatas++];
376 
377  rdata->data = data;
378  rdata->len = len;
379 
380  /*
381  * we use the mainrdata_last pointer to track the end of the chain, so no
382  * need to clear 'next' here.
383  */
384 
385  mainrdata_last->next = rdata;
386  mainrdata_last = rdata;
387 
388  mainrdata_len += len;
389 }
390 
391 /*
392  * Add buffer-specific data to the WAL record that's being constructed.
393  *
394  * Block_id must reference a block previously registered with
395  * XLogRegisterBuffer(). If this is called more than once for the same
396  * block_id, the data is appended.
397  *
398  * The maximum amount of data that can be registered per block is 65535
399  * bytes. That should be plenty; if you need more than BLCKSZ bytes to
400  * reconstruct the changes to the page, you might as well just log a full
401  * copy of it. (the "main data" that's not associated with a block is not
402  * limited)
403  */
404 void
406 {
407  registered_buffer *regbuf;
408  XLogRecData *rdata;
409 
411 
412  /* find the registered buffer struct */
413  regbuf = &registered_buffers[block_id];
414  if (!regbuf->in_use)
415  elog(ERROR, "no block with id %d registered with WAL insertion",
416  block_id);
417 
418  /*
419  * Check against max_rdatas and ensure we do not register more data per
420  * buffer than can be handled by the physical data format; i.e. that
421  * regbuf->rdata_len does not grow beyond what
422  * XLogRecordBlockHeader->data_length can hold.
423  */
424  if (num_rdatas >= max_rdatas)
425  ereport(ERROR,
426  (errmsg_internal("too much WAL data"),
427  errdetail_internal("%d out of %d data segments are already in use.",
429  if (regbuf->rdata_len + len > UINT16_MAX || len > UINT16_MAX)
430  ereport(ERROR,
431  (errmsg_internal("too much WAL data"),
432  errdetail_internal("Registering more than maximum %u bytes allowed to block %u: current %u bytes, adding %u bytes.",
433  UINT16_MAX, block_id, regbuf->rdata_len, len)));
434 
435  rdata = &rdatas[num_rdatas++];
436 
437  rdata->data = data;
438  rdata->len = len;
439 
440  regbuf->rdata_tail->next = rdata;
441  regbuf->rdata_tail = rdata;
442  regbuf->rdata_len += len;
443 }
444 
445 /*
446  * Set insert status flags for the upcoming WAL record.
447  *
448  * The flags that can be used here are:
449  * - XLOG_INCLUDE_ORIGIN, to determine if the replication origin should be
450  * included in the record.
451  * - XLOG_MARK_UNIMPORTANT, to signal that the record is not important for
452  * durability, which allows to avoid triggering WAL archiving and other
453  * background activity.
454  */
455 void
457 {
459  curinsert_flags |= flags;
460 }
461 
462 /*
463  * Insert an XLOG record having the specified RMID and info bytes, with the
464  * body of the record being the data and buffer references registered earlier
465  * with XLogRegister* calls.
466  *
467  * Returns XLOG pointer to end of record (beginning of next record).
468  * This can be used as LSN for data pages affected by the logged action.
469  * (LSN is the XLOG point up to which the XLOG must be flushed to disk
470  * before the data page can be written out. This implements the basic
471  * WAL rule "write the log before the data".)
472  */
475 {
476  XLogRecPtr EndPos;
477 
478  /* XLogBeginInsert() must have been called. */
479  if (!begininsert_called)
480  elog(ERROR, "XLogBeginInsert was not called");
481 
482  /*
483  * The caller can set rmgr bits, XLR_SPECIAL_REL_UPDATE and
484  * XLR_CHECK_CONSISTENCY; the rest are reserved for use by me.
485  */
486  if ((info & ~(XLR_RMGR_INFO_MASK |
488  XLR_CHECK_CONSISTENCY)) != 0)
489  elog(PANIC, "invalid xlog info mask %02X", info);
490 
491  TRACE_POSTGRESQL_WAL_INSERT(rmid, info);
492 
493  /*
494  * In bootstrap mode, we don't actually log anything but XLOG resources;
495  * return a phony record pointer.
496  */
497  if (IsBootstrapProcessingMode() && rmid != RM_XLOG_ID)
498  {
500  EndPos = SizeOfXLogLongPHD; /* start of 1st chkpt record */
501  return EndPos;
502  }
503 
504  do
505  {
507  bool doPageWrites;
508  bool topxid_included = false;
509  XLogRecPtr fpw_lsn;
510  XLogRecData *rdt;
511  int num_fpi = 0;
512 
513  /*
514  * Get values needed to decide whether to do full-page writes. Since
515  * we don't yet have an insertion lock, these could change under us,
516  * but XLogInsertRecord will recheck them once it has a lock.
517  */
519 
520  rdt = XLogRecordAssemble(rmid, info, RedoRecPtr, doPageWrites,
521  &fpw_lsn, &num_fpi, &topxid_included);
522 
523  EndPos = XLogInsertRecord(rdt, fpw_lsn, curinsert_flags, num_fpi,
524  topxid_included);
525  } while (EndPos == InvalidXLogRecPtr);
526 
528 
529  return EndPos;
530 }
531 
532 /*
533  * Assemble a WAL record from the registered data and buffers into an
534  * XLogRecData chain, ready for insertion with XLogInsertRecord().
535  *
536  * The record header fields are filled in, except for the xl_prev field. The
537  * calculated CRC does not include the record header yet.
538  *
539  * If there are any registered buffers, and a full-page image was not taken
540  * of all of them, *fpw_lsn is set to the lowest LSN among such pages. This
541  * signals that the assembled record is only good for insertion on the
542  * assumption that the RedoRecPtr and doPageWrites values were up-to-date.
543  *
544  * *topxid_included is set if the topmost transaction ID is logged with the
545  * current subtransaction.
546  */
547 static XLogRecData *
550  XLogRecPtr *fpw_lsn, int *num_fpi, bool *topxid_included)
551 {
552  XLogRecData *rdt;
553  uint64 total_len = 0;
554  int block_id;
555  pg_crc32c rdata_crc;
556  registered_buffer *prev_regbuf = NULL;
557  XLogRecData *rdt_datas_last;
558  XLogRecord *rechdr;
559  char *scratch = hdr_scratch;
560 
561  /*
562  * Note: this function can be called multiple times for the same record.
563  * All the modifications we do to the rdata chains below must handle that.
564  */
565 
566  /* The record begins with the fixed-size header */
567  rechdr = (XLogRecord *) scratch;
568  scratch += SizeOfXLogRecord;
569 
570  hdr_rdt.next = NULL;
571  rdt_datas_last = &hdr_rdt;
573 
574  /*
575  * Enforce consistency checks for this record if user is looking for it.
576  * Do this before at the beginning of this routine to give the possibility
577  * for callers of XLogInsert() to pass XLR_CHECK_CONSISTENCY directly for
578  * a record.
579  */
580  if (wal_consistency_checking[rmid])
581  info |= XLR_CHECK_CONSISTENCY;
582 
583  /*
584  * Make an rdata chain containing all the data portions of all block
585  * references. This includes the data for full-page images. Also append
586  * the headers for the block references in the scratch buffer.
587  */
588  *fpw_lsn = InvalidXLogRecPtr;
589  for (block_id = 0; block_id < max_registered_block_id; block_id++)
590  {
591  registered_buffer *regbuf = &registered_buffers[block_id];
592  bool needs_backup;
593  bool needs_data;
596  XLogRecordBlockCompressHeader cbimg = {0};
597  bool samerel;
598  bool is_compressed = false;
599  bool include_image;
600 
601  if (!regbuf->in_use)
602  continue;
603 
604  /* Determine if this block needs to be backed up */
605  if (regbuf->flags & REGBUF_FORCE_IMAGE)
606  needs_backup = true;
607  else if (regbuf->flags & REGBUF_NO_IMAGE)
608  needs_backup = false;
609  else if (!doPageWrites)
610  needs_backup = false;
611  else
612  {
613  /*
614  * We assume page LSN is first data on *every* page that can be
615  * passed to XLogInsert, whether it has the standard page layout
616  * or not.
617  */
618  XLogRecPtr page_lsn = PageGetLSN(regbuf->page);
619 
620  needs_backup = (page_lsn <= RedoRecPtr);
621  if (!needs_backup)
622  {
623  if (*fpw_lsn == InvalidXLogRecPtr || page_lsn < *fpw_lsn)
624  *fpw_lsn = page_lsn;
625  }
626  }
627 
628  /* Determine if the buffer data needs to included */
629  if (regbuf->rdata_len == 0)
630  needs_data = false;
631  else if ((regbuf->flags & REGBUF_KEEP_DATA) != 0)
632  needs_data = true;
633  else
634  needs_data = !needs_backup;
635 
636  bkpb.id = block_id;
637  bkpb.fork_flags = regbuf->forkno;
638  bkpb.data_length = 0;
639 
640  if ((regbuf->flags & REGBUF_WILL_INIT) == REGBUF_WILL_INIT)
642 
643  /*
644  * If needs_backup is true or WAL checking is enabled for current
645  * resource manager, log a full-page write for the current block.
646  */
647  include_image = needs_backup || (info & XLR_CHECK_CONSISTENCY) != 0;
648 
649  if (include_image)
650  {
651  Page page = regbuf->page;
652  uint16 compressed_len = 0;
653 
654  /*
655  * The page needs to be backed up, so calculate its hole length
656  * and offset.
657  */
658  if (regbuf->flags & REGBUF_STANDARD)
659  {
660  /* Assume we can omit data between pd_lower and pd_upper */
661  uint16 lower = ((PageHeader) page)->pd_lower;
662  uint16 upper = ((PageHeader) page)->pd_upper;
663 
664  if (lower >= SizeOfPageHeaderData &&
665  upper > lower &&
666  upper <= BLCKSZ)
667  {
668  bimg.hole_offset = lower;
669  cbimg.hole_length = upper - lower;
670  }
671  else
672  {
673  /* No "hole" to remove */
674  bimg.hole_offset = 0;
675  cbimg.hole_length = 0;
676  }
677  }
678  else
679  {
680  /* Not a standard page header, don't try to eliminate "hole" */
681  bimg.hole_offset = 0;
682  cbimg.hole_length = 0;
683  }
684 
685  /*
686  * Try to compress a block image if wal_compression is enabled
687  */
689  {
690  is_compressed =
692  cbimg.hole_length,
693  regbuf->compressed_page,
694  &compressed_len);
695  }
696 
697  /*
698  * Fill in the remaining fields in the XLogRecordBlockHeader
699  * struct
700  */
702 
703  /* Report a full page image constructed for the WAL record */
704  *num_fpi += 1;
705 
706  /*
707  * Construct XLogRecData entries for the page content.
708  */
709  rdt_datas_last->next = &regbuf->bkp_rdatas[0];
710  rdt_datas_last = rdt_datas_last->next;
711 
712  bimg.bimg_info = (cbimg.hole_length == 0) ? 0 : BKPIMAGE_HAS_HOLE;
713 
714  /*
715  * If WAL consistency checking is enabled for the resource manager
716  * of this WAL record, a full-page image is included in the record
717  * for the block modified. During redo, the full-page is replayed
718  * only if BKPIMAGE_APPLY is set.
719  */
720  if (needs_backup)
721  bimg.bimg_info |= BKPIMAGE_APPLY;
722 
723  if (is_compressed)
724  {
725  /* The current compression is stored in the WAL record */
726  bimg.length = compressed_len;
727 
728  /* Set the compression method used for this block */
730  {
733  break;
734 
735  case WAL_COMPRESSION_LZ4:
736 #ifdef USE_LZ4
738 #else
739  elog(ERROR, "LZ4 is not supported by this build");
740 #endif
741  break;
742 
744 #ifdef USE_ZSTD
746 #else
747  elog(ERROR, "zstd is not supported by this build");
748 #endif
749  break;
750 
752  Assert(false); /* cannot happen */
753  break;
754  /* no default case, so that compiler will warn */
755  }
756 
757  rdt_datas_last->data = regbuf->compressed_page;
758  rdt_datas_last->len = compressed_len;
759  }
760  else
761  {
762  bimg.length = BLCKSZ - cbimg.hole_length;
763 
764  if (cbimg.hole_length == 0)
765  {
766  rdt_datas_last->data = page;
767  rdt_datas_last->len = BLCKSZ;
768  }
769  else
770  {
771  /* must skip the hole */
772  rdt_datas_last->data = page;
773  rdt_datas_last->len = bimg.hole_offset;
774 
775  rdt_datas_last->next = &regbuf->bkp_rdatas[1];
776  rdt_datas_last = rdt_datas_last->next;
777 
778  rdt_datas_last->data =
779  page + (bimg.hole_offset + cbimg.hole_length);
780  rdt_datas_last->len =
781  BLCKSZ - (bimg.hole_offset + cbimg.hole_length);
782  }
783  }
784 
785  total_len += bimg.length;
786  }
787 
788  if (needs_data)
789  {
790  /*
791  * When copying to XLogRecordBlockHeader, the length is narrowed
792  * to an uint16. Double-check that it is still correct.
793  */
794  Assert(regbuf->rdata_len <= UINT16_MAX);
795 
796  /*
797  * Link the caller-supplied rdata chain for this buffer to the
798  * overall list.
799  */
801  bkpb.data_length = (uint16) regbuf->rdata_len;
802  total_len += regbuf->rdata_len;
803 
804  rdt_datas_last->next = regbuf->rdata_head;
805  rdt_datas_last = regbuf->rdata_tail;
806  }
807 
808  if (prev_regbuf && RelFileLocatorEquals(regbuf->rlocator, prev_regbuf->rlocator))
809  {
810  samerel = true;
812  }
813  else
814  samerel = false;
815  prev_regbuf = regbuf;
816 
817  /* Ok, copy the header to the scratch buffer */
818  memcpy(scratch, &bkpb, SizeOfXLogRecordBlockHeader);
819  scratch += SizeOfXLogRecordBlockHeader;
820  if (include_image)
821  {
822  memcpy(scratch, &bimg, SizeOfXLogRecordBlockImageHeader);
824  if (cbimg.hole_length != 0 && is_compressed)
825  {
826  memcpy(scratch, &cbimg,
829  }
830  }
831  if (!samerel)
832  {
833  memcpy(scratch, &regbuf->rlocator, sizeof(RelFileLocator));
834  scratch += sizeof(RelFileLocator);
835  }
836  memcpy(scratch, &regbuf->block, sizeof(BlockNumber));
837  scratch += sizeof(BlockNumber);
838  }
839 
840  /* followed by the record's origin, if any */
843  {
844  *(scratch++) = (char) XLR_BLOCK_ID_ORIGIN;
845  memcpy(scratch, &replorigin_session_origin, sizeof(replorigin_session_origin));
846  scratch += sizeof(replorigin_session_origin);
847  }
848 
849  /* followed by toplevel XID, if not already included in previous record */
851  {
853 
854  /* Set the flag that the top xid is included in the WAL */
855  *topxid_included = true;
856 
857  *(scratch++) = (char) XLR_BLOCK_ID_TOPLEVEL_XID;
858  memcpy(scratch, &xid, sizeof(TransactionId));
859  scratch += sizeof(TransactionId);
860  }
861 
862  /* followed by main data, if any */
863  if (mainrdata_len > 0)
864  {
865  if (mainrdata_len > 255)
866  {
867  uint32 mainrdata_len_4b;
868 
870  ereport(ERROR,
871  (errmsg_internal("too much WAL data"),
872  errdetail_internal("Main data length is %llu bytes for a maximum of %u bytes.",
873  (unsigned long long) mainrdata_len,
874  PG_UINT32_MAX)));
875 
876  mainrdata_len_4b = (uint32) mainrdata_len;
877  *(scratch++) = (char) XLR_BLOCK_ID_DATA_LONG;
878  memcpy(scratch, &mainrdata_len_4b, sizeof(uint32));
879  scratch += sizeof(uint32);
880  }
881  else
882  {
883  *(scratch++) = (char) XLR_BLOCK_ID_DATA_SHORT;
884  *(scratch++) = (uint8) mainrdata_len;
885  }
886  rdt_datas_last->next = mainrdata_head;
887  rdt_datas_last = mainrdata_last;
888  total_len += mainrdata_len;
889  }
890  rdt_datas_last->next = NULL;
891 
892  hdr_rdt.len = (scratch - hdr_scratch);
893  total_len += hdr_rdt.len;
894 
895  /*
896  * Calculate CRC of the data
897  *
898  * Note that the record header isn't added into the CRC initially since we
899  * don't know the prev-link yet. Thus, the CRC will represent the CRC of
900  * the whole record in the order: rdata, then backup blocks, then record
901  * header.
902  */
903  INIT_CRC32C(rdata_crc);
905  for (rdt = hdr_rdt.next; rdt != NULL; rdt = rdt->next)
906  COMP_CRC32C(rdata_crc, rdt->data, rdt->len);
907 
908  /*
909  * Ensure that the XLogRecord is not too large.
910  *
911  * XLogReader machinery is only able to handle records up to a certain
912  * size (ignoring machine resource limitations), so make sure that we will
913  * not emit records larger than the sizes advertised to be supported.
914  */
915  if (total_len > XLogRecordMaxSize)
916  ereport(ERROR,
917  (errmsg_internal("oversized WAL record"),
918  errdetail_internal("WAL record would be %llu bytes (of maximum %u bytes); rmid %u flags %u.",
919  (unsigned long long) total_len, XLogRecordMaxSize, rmid, info)));
920 
921  /*
922  * Fill in the fields in the record header. Prev-link is filled in later,
923  * once we know where in the WAL the record will be inserted. The CRC does
924  * not include the record header yet.
925  */
927  rechdr->xl_tot_len = (uint32) total_len;
928  rechdr->xl_info = info;
929  rechdr->xl_rmid = rmid;
930  rechdr->xl_prev = InvalidXLogRecPtr;
931  rechdr->xl_crc = rdata_crc;
932 
933  return &hdr_rdt;
934 }
935 
936 /*
937  * Create a compressed version of a backup block image.
938  *
939  * Returns false if compression fails (i.e., compressed result is actually
940  * bigger than original). Otherwise, returns true and sets 'dlen' to
941  * the length of compressed block image.
942  */
943 static bool
944 XLogCompressBackupBlock(char *page, uint16 hole_offset, uint16 hole_length,
945  char *dest, uint16 *dlen)
946 {
947  int32 orig_len = BLCKSZ - hole_length;
948  int32 len = -1;
949  int32 extra_bytes = 0;
950  char *source;
951  PGAlignedBlock tmp;
952 
953  if (hole_length != 0)
954  {
955  /* must skip the hole */
956  source = tmp.data;
957  memcpy(source, page, hole_offset);
958  memcpy(source + hole_offset,
959  page + (hole_offset + hole_length),
960  BLCKSZ - (hole_length + hole_offset));
961 
962  /*
963  * Extra data needs to be stored in WAL record for the compressed
964  * version of block image if the hole exists.
965  */
967  }
968  else
969  source = page;
970 
972  {
975  break;
976 
977  case WAL_COMPRESSION_LZ4:
978 #ifdef USE_LZ4
979  len = LZ4_compress_default(source, dest, orig_len,
981  if (len <= 0)
982  len = -1; /* failure */
983 #else
984  elog(ERROR, "LZ4 is not supported by this build");
985 #endif
986  break;
987 
989 #ifdef USE_ZSTD
990  len = ZSTD_compress(dest, COMPRESS_BUFSIZE, source, orig_len,
991  ZSTD_CLEVEL_DEFAULT);
992  if (ZSTD_isError(len))
993  len = -1; /* failure */
994 #else
995  elog(ERROR, "zstd is not supported by this build");
996 #endif
997  break;
998 
1000  Assert(false); /* cannot happen */
1001  break;
1002  /* no default case, so that compiler will warn */
1003  }
1004 
1005  /*
1006  * We recheck the actual size even if compression reports success and see
1007  * if the number of bytes saved by compression is larger than the length
1008  * of extra data needed for the compressed version of block image.
1009  */
1010  if (len >= 0 &&
1011  len + extra_bytes < orig_len)
1012  {
1013  *dlen = (uint16) len; /* successful compression */
1014  return true;
1015  }
1016  return false;
1017 }
1018 
1019 /*
1020  * Determine whether the buffer referenced has to be backed up.
1021  *
1022  * Since we don't yet have the insert lock, fullPageWrites and runningBackups
1023  * (which forces full-page writes) could change later, so the result should
1024  * be used for optimization purposes only.
1025  */
1026 bool
1028 {
1030  bool doPageWrites;
1031  Page page;
1032 
1034 
1035  page = BufferGetPage(buffer);
1036 
1037  if (doPageWrites && PageGetLSN(page) <= RedoRecPtr)
1038  return true; /* buffer requires backup */
1039 
1040  return false; /* buffer does not need to be backed up */
1041 }
1042 
1043 /*
1044  * Write a backup block if needed when we are setting a hint. Note that
1045  * this may be called for a variety of page types, not just heaps.
1046  *
1047  * Callable while holding just share lock on the buffer content.
1048  *
1049  * We can't use the plain backup block mechanism since that relies on the
1050  * Buffer being exclusively locked. Since some modifications (setting LSN, hint
1051  * bits) are allowed in a sharelocked buffer that can lead to wal checksum
1052  * failures. So instead we copy the page and insert the copied data as normal
1053  * record data.
1054  *
1055  * We only need to do something if page has not yet been full page written in
1056  * this checkpoint round. The LSN of the inserted wal record is returned if we
1057  * had to write, InvalidXLogRecPtr otherwise.
1058  *
1059  * It is possible that multiple concurrent backends could attempt to write WAL
1060  * records. In that case, multiple copies of the same block would be recorded
1061  * in separate WAL records by different backends, though that is still OK from
1062  * a correctness perspective.
1063  */
1064 XLogRecPtr
1065 XLogSaveBufferForHint(Buffer buffer, bool buffer_std)
1066 {
1067  XLogRecPtr recptr = InvalidXLogRecPtr;
1068  XLogRecPtr lsn;
1070 
1071  /*
1072  * Ensure no checkpoint can change our view of RedoRecPtr.
1073  */
1075 
1076  /*
1077  * Update RedoRecPtr so that we can make the right decision
1078  */
1080 
1081  /*
1082  * We assume page LSN is first data on *every* page that can be passed to
1083  * XLogInsert, whether it has the standard page layout or not. Since we're
1084  * only holding a share-lock on the page, we must take the buffer header
1085  * lock when we look at the LSN.
1086  */
1087  lsn = BufferGetLSNAtomic(buffer);
1088 
1089  if (lsn <= RedoRecPtr)
1090  {
1091  int flags = 0;
1092  PGAlignedBlock copied_buffer;
1093  char *origdata = (char *) BufferGetBlock(buffer);
1094  RelFileLocator rlocator;
1095  ForkNumber forkno;
1096  BlockNumber blkno;
1097 
1098  /*
1099  * Copy buffer so we don't have to worry about concurrent hint bit or
1100  * lsn updates. We assume pd_lower/upper cannot be changed without an
1101  * exclusive lock, so the contents bkp are not racy.
1102  */
1103  if (buffer_std)
1104  {
1105  /* Assume we can omit data between pd_lower and pd_upper */
1106  Page page = BufferGetPage(buffer);
1107  uint16 lower = ((PageHeader) page)->pd_lower;
1108  uint16 upper = ((PageHeader) page)->pd_upper;
1109 
1110  memcpy(copied_buffer.data, origdata, lower);
1111  memcpy(copied_buffer.data + upper, origdata + upper, BLCKSZ - upper);
1112  }
1113  else
1114  memcpy(copied_buffer.data, origdata, BLCKSZ);
1115 
1116  XLogBeginInsert();
1117 
1118  if (buffer_std)
1119  flags |= REGBUF_STANDARD;
1120 
1121  BufferGetTag(buffer, &rlocator, &forkno, &blkno);
1122  XLogRegisterBlock(0, &rlocator, forkno, blkno, copied_buffer.data, flags);
1123 
1124  recptr = XLogInsert(RM_XLOG_ID, XLOG_FPI_FOR_HINT);
1125  }
1126 
1127  return recptr;
1128 }
1129 
1130 /*
1131  * Write a WAL record containing a full image of a page. Caller is responsible
1132  * for writing the page to disk after calling this routine.
1133  *
1134  * Note: If you're using this function, you should be building pages in private
1135  * memory and writing them directly to smgr. If you're using buffers, call
1136  * log_newpage_buffer instead.
1137  *
1138  * If the page follows the standard page layout, with a PageHeader and unused
1139  * space between pd_lower and pd_upper, set 'page_std' to true. That allows
1140  * the unused space to be left out from the WAL record, making it smaller.
1141  */
1142 XLogRecPtr
1144  Page page, bool page_std)
1145 {
1146  int flags;
1147  XLogRecPtr recptr;
1148 
1149  flags = REGBUF_FORCE_IMAGE;
1150  if (page_std)
1151  flags |= REGBUF_STANDARD;
1152 
1153  XLogBeginInsert();
1154  XLogRegisterBlock(0, rlocator, forknum, blkno, page, flags);
1155  recptr = XLogInsert(RM_XLOG_ID, XLOG_FPI);
1156 
1157  /*
1158  * The page may be uninitialized. If so, we can't set the LSN because that
1159  * would corrupt the page.
1160  */
1161  if (!PageIsNew(page))
1162  {
1163  PageSetLSN(page, recptr);
1164  }
1165 
1166  return recptr;
1167 }
1168 
1169 /*
1170  * Like log_newpage(), but allows logging multiple pages in one operation.
1171  * It is more efficient than calling log_newpage() for each page separately,
1172  * because we can write multiple pages in a single WAL record.
1173  */
1174 void
1175 log_newpages(RelFileLocator *rlocator, ForkNumber forknum, int num_pages,
1176  BlockNumber *blknos, Page *pages, bool page_std)
1177 {
1178  int flags;
1179  XLogRecPtr recptr;
1180  int i;
1181  int j;
1182 
1183  flags = REGBUF_FORCE_IMAGE;
1184  if (page_std)
1185  flags |= REGBUF_STANDARD;
1186 
1187  /*
1188  * Iterate over all the pages. They are collected into batches of
1189  * XLR_MAX_BLOCK_ID pages, and a single WAL-record is written for each
1190  * batch.
1191  */
1193 
1194  i = 0;
1195  while (i < num_pages)
1196  {
1197  int batch_start = i;
1198  int nbatch;
1199 
1200  XLogBeginInsert();
1201 
1202  nbatch = 0;
1203  while (nbatch < XLR_MAX_BLOCK_ID && i < num_pages)
1204  {
1205  XLogRegisterBlock(nbatch, rlocator, forknum, blknos[i], pages[i], flags);
1206  i++;
1207  nbatch++;
1208  }
1209 
1210  recptr = XLogInsert(RM_XLOG_ID, XLOG_FPI);
1211 
1212  for (j = batch_start; j < i; j++)
1213  {
1214  /*
1215  * The page may be uninitialized. If so, we can't set the LSN
1216  * because that would corrupt the page.
1217  */
1218  if (!PageIsNew(pages[j]))
1219  {
1220  PageSetLSN(pages[j], recptr);
1221  }
1222  }
1223  }
1224 }
1225 
1226 /*
1227  * Write a WAL record containing a full image of a page.
1228  *
1229  * Caller should initialize the buffer and mark it dirty before calling this
1230  * function. This function will set the page LSN.
1231  *
1232  * If the page follows the standard page layout, with a PageHeader and unused
1233  * space between pd_lower and pd_upper, set 'page_std' to true. That allows
1234  * the unused space to be left out from the WAL record, making it smaller.
1235  */
1236 XLogRecPtr
1237 log_newpage_buffer(Buffer buffer, bool page_std)
1238 {
1239  Page page = BufferGetPage(buffer);
1240  RelFileLocator rlocator;
1241  ForkNumber forknum;
1242  BlockNumber blkno;
1243 
1244  /* Shared buffers should be modified in a critical section. */
1245  Assert(CritSectionCount > 0);
1246 
1247  BufferGetTag(buffer, &rlocator, &forknum, &blkno);
1248 
1249  return log_newpage(&rlocator, forknum, blkno, page, page_std);
1250 }
1251 
1252 /*
1253  * WAL-log a range of blocks in a relation.
1254  *
1255  * An image of all pages with block numbers 'startblk' <= X < 'endblk' is
1256  * written to the WAL. If the range is large, this is done in multiple WAL
1257  * records.
1258  *
1259  * If all page follows the standard page layout, with a PageHeader and unused
1260  * space between pd_lower and pd_upper, set 'page_std' to true. That allows
1261  * the unused space to be left out from the WAL records, making them smaller.
1262  *
1263  * NOTE: This function acquires exclusive-locks on the pages. Typically, this
1264  * is used on a newly-built relation, and the caller is holding a
1265  * AccessExclusiveLock on it, so no other backend can be accessing it at the
1266  * same time. If that's not the case, you must ensure that this does not
1267  * cause a deadlock through some other means.
1268  */
1269 void
1271  BlockNumber startblk, BlockNumber endblk,
1272  bool page_std)
1273 {
1274  int flags;
1275  BlockNumber blkno;
1276 
1277  flags = REGBUF_FORCE_IMAGE;
1278  if (page_std)
1279  flags |= REGBUF_STANDARD;
1280 
1281  /*
1282  * Iterate over all the pages in the range. They are collected into
1283  * batches of XLR_MAX_BLOCK_ID pages, and a single WAL-record is written
1284  * for each batch.
1285  */
1287 
1288  blkno = startblk;
1289  while (blkno < endblk)
1290  {
1291  Buffer bufpack[XLR_MAX_BLOCK_ID];
1292  XLogRecPtr recptr;
1293  int nbufs;
1294  int i;
1295 
1297 
1298  /* Collect a batch of blocks. */
1299  nbufs = 0;
1300  while (nbufs < XLR_MAX_BLOCK_ID && blkno < endblk)
1301  {
1302  Buffer buf = ReadBufferExtended(rel, forknum, blkno,
1303  RBM_NORMAL, NULL);
1304 
1306 
1307  /*
1308  * Completely empty pages are not WAL-logged. Writing a WAL record
1309  * would change the LSN, and we don't want that. We want the page
1310  * to stay empty.
1311  */
1312  if (!PageIsNew(BufferGetPage(buf)))
1313  bufpack[nbufs++] = buf;
1314  else
1316  blkno++;
1317  }
1318 
1319  /* Nothing more to do if all remaining blocks were empty. */
1320  if (nbufs == 0)
1321  break;
1322 
1323  /* Write WAL record for this batch. */
1324  XLogBeginInsert();
1325 
1327  for (i = 0; i < nbufs; i++)
1328  {
1329  MarkBufferDirty(bufpack[i]);
1330  XLogRegisterBuffer(i, bufpack[i], flags);
1331  }
1332 
1333  recptr = XLogInsert(RM_XLOG_ID, XLOG_FPI);
1334 
1335  for (i = 0; i < nbufs; i++)
1336  {
1337  PageSetLSN(BufferGetPage(bufpack[i]), recptr);
1338  UnlockReleaseBuffer(bufpack[i]);
1339  }
1340  END_CRIT_SECTION();
1341  }
1342 }
1343 
1344 /*
1345  * Allocate working buffers needed for WAL record construction.
1346  */
1347 void
1349 {
1350 #ifdef USE_ASSERT_CHECKING
1351 
1352  /*
1353  * Check that any records assembled can be decoded. This is capped based
1354  * on what XLogReader would require at its maximum bound. The XLOG_BLCKSZ
1355  * addend covers the larger allocate_recordbuf() demand. This code path
1356  * is called once per backend, more than enough for this check.
1357  */
1358  size_t max_required =
1360 
1361  Assert(AllocSizeIsValid(max_required));
1362 #endif
1363 
1364  /* Initialize the working areas */
1365  if (xloginsert_cxt == NULL)
1366  {
1368  "WAL record construction",
1370  }
1371 
1372  if (registered_buffers == NULL)
1373  {
1376  sizeof(registered_buffer) * (XLR_NORMAL_MAX_BLOCK_ID + 1));
1378  }
1379  if (rdatas == NULL)
1380  {
1382  sizeof(XLogRecData) * XLR_NORMAL_RDATAS);
1384  }
1385 
1386  /*
1387  * Allocate a buffer to hold the header information for a WAL record.
1388  */
1389  if (hdr_scratch == NULL)
1392 }
uint32 BlockNumber
Definition: block.h:31
int Buffer
Definition: buf.h:23
bool BufferIsExclusiveLocked(Buffer buffer)
Definition: bufmgr.c:2482
void BufferGetTag(Buffer buffer, RelFileLocator *rlocator, ForkNumber *forknum, BlockNumber *blknum)
Definition: bufmgr.c:3757
bool BufferIsDirty(Buffer buffer)
Definition: bufmgr.c:2511
XLogRecPtr BufferGetLSNAtomic(Buffer buffer)
Definition: bufmgr.c:3997
void UnlockReleaseBuffer(Buffer buffer)
Definition: bufmgr.c:4953
void MarkBufferDirty(Buffer buffer)
Definition: bufmgr.c:2543
void LockBuffer(Buffer buffer, int mode)
Definition: bufmgr.c:5171
Buffer ReadBufferExtended(Relation reln, ForkNumber forkNum, BlockNumber blockNum, ReadBufferMode mode, BufferAccessStrategy strategy)
Definition: bufmgr.c:820
static Page BufferGetPage(Buffer buffer)
Definition: bufmgr.h:400
static Block BufferGetBlock(Buffer buffer)
Definition: bufmgr.h:367
#define BUFFER_LOCK_EXCLUSIVE
Definition: bufmgr.h:191
@ RBM_NORMAL
Definition: bufmgr.h:45
PageHeaderData * PageHeader
Definition: bufpage.h:170
Pointer Page
Definition: bufpage.h:78
#define SizeOfPageHeaderData
Definition: bufpage.h:213
static bool PageIsNew(Page page)
Definition: bufpage.h:230
static void PageSetLSN(Page page, XLogRecPtr lsn)
Definition: bufpage.h:388
static XLogRecPtr PageGetLSN(Page page)
Definition: bufpage.h:383
unsigned short uint16
Definition: c.h:505
unsigned int uint32
Definition: c.h:506
#define PG_UINT32_MAX
Definition: c.h:590
signed int int32
Definition: c.h:494
#define Assert(condition)
Definition: c.h:858
unsigned char uint8
Definition: c.h:504
#define MemSet(start, val, len)
Definition: c.h:1020
uint32 TransactionId
Definition: c.h:652
int errmsg_internal(const char *fmt,...)
Definition: elog.c:1159
int errdetail_internal(const char *fmt,...)
Definition: elog.c:1232
#define PANIC
Definition: elog.h:42
#define ERROR
Definition: elog.h:39
#define elog(elevel,...)
Definition: elog.h:224
#define ereport(elevel,...)
Definition: elog.h:149
volatile uint32 CritSectionCount
Definition: globals.c:44
for(;;)
int j
Definition: isn.c:74
int i
Definition: isn.c:73
MemoryContext TopMemoryContext
Definition: mcxt.c:149
void * MemoryContextAllocZero(MemoryContext context, Size size)
Definition: mcxt.c:1215
void * repalloc(void *pointer, Size size)
Definition: mcxt.c:1541
void * MemoryContextAlloc(MemoryContext context, Size size)
Definition: mcxt.c:1181
#define AllocSetContextCreate
Definition: memutils.h:129
#define ALLOCSET_DEFAULT_SIZES
Definition: memutils.h:160
#define AllocSizeIsValid(size)
Definition: memutils.h:42
#define IsBootstrapProcessingMode()
Definition: miscadmin.h:454
#define START_CRIT_SECTION()
Definition: miscadmin.h:149
#define CHECK_FOR_INTERRUPTS()
Definition: miscadmin.h:122
#define END_CRIT_SECTION()
Definition: miscadmin.h:151
Datum lower(PG_FUNCTION_ARGS)
Definition: oracle_compat.c:49
Datum upper(PG_FUNCTION_ARGS)
Definition: oracle_compat.c:80
RepOriginId replorigin_session_origin
Definition: origin.c:155
#define InvalidRepOriginId
Definition: origin.h:33
#define XLOG_FPI
Definition: pg_control.h:79
#define XLOG_FPI_FOR_HINT
Definition: pg_control.h:78
uint32 pg_crc32c
Definition: pg_crc32c.h:38
#define COMP_CRC32C(crc, data, len)
Definition: pg_crc32c.h:98
#define INIT_CRC32C(crc)
Definition: pg_crc32c.h:41
const void size_t len
const void * data
const PGLZ_Strategy *const PGLZ_strategy_default
int32 pglz_compress(const char *source, int32 slen, char *dest, const PGLZ_Strategy *strategy)
static rewind_source * source
Definition: pg_rewind.c:89
static char * buf
Definition: pg_test_fsync.c:73
#define DELAY_CHKPT_START
Definition: proc.h:114
struct RelFileLocator RelFileLocator
#define RelFileLocatorEquals(locator1, locator2)
ForkNumber
Definition: relpath.h:48
uint8 RmgrId
Definition: rmgr.h:11
PGPROC * MyProc
Definition: proc.c:66
int delayChkptFlags
Definition: proc.h:235
struct XLogRecData * next
XLogRecPtr xl_prev
Definition: xlogrecord.h:45
pg_crc32c xl_crc
Definition: xlogrecord.h:49
uint8 xl_info
Definition: xlogrecord.h:46
uint32 xl_tot_len
Definition: xlogrecord.h:43
TransactionId xl_xid
Definition: xlogrecord.h:44
RmgrId xl_rmid
Definition: xlogrecord.h:47
XLogRecData bkp_rdatas[2]
Definition: xloginsert.c:82
char compressed_page[COMPRESS_BUFSIZE]
Definition: xloginsert.c:86
XLogRecData * rdata_tail
Definition: xloginsert.c:79
BlockNumber block
Definition: xloginsert.c:74
XLogRecData * rdata_head
Definition: xloginsert.c:77
ForkNumber forkno
Definition: xloginsert.c:73
RelFileLocator rlocator
Definition: xloginsert.c:72
char data[BLCKSZ]
Definition: c.h:1119
TransactionId GetTopTransactionIdIfAny(void)
Definition: xact.c:439
TransactionId GetCurrentTransactionIdIfAny(void)
Definition: xact.c:469
bool IsSubxactTopXidLogPending(void)
Definition: xact.c:557
void GetFullPageWriteInfo(XLogRecPtr *RedoRecPtr_p, bool *doPageWrites_p)
Definition: xlog.c:6425
XLogRecPtr GetRedoRecPtr(void)
Definition: xlog.c:6395
static XLogRecPtr RedoRecPtr
Definition: xlog.c:273
XLogRecPtr XLogInsertRecord(XLogRecData *rdata, XLogRecPtr fpw_lsn, uint8 flags, int num_fpi, bool topxid_included)
Definition: xlog.c:743
static bool doPageWrites
Definition: xlog.c:286
int wal_compression
Definition: xlog.c:124
bool XLogInsertAllowed(void)
Definition: xlog.c:6347
bool * wal_consistency_checking
Definition: xlog.c:126
#define XLOG_INCLUDE_ORIGIN
Definition: xlog.h:152
WalCompression
Definition: xlog.h:79
@ WAL_COMPRESSION_NONE
Definition: xlog.h:80
@ WAL_COMPRESSION_LZ4
Definition: xlog.h:82
@ WAL_COMPRESSION_PGLZ
Definition: xlog.h:81
@ WAL_COMPRESSION_ZSTD
Definition: xlog.h:83
#define SizeOfXLogLongPHD
Definition: xlog_internal.h:69
uint64 XLogRecPtr
Definition: xlogdefs.h:21
#define InvalidXLogRecPtr
Definition: xlogdefs.h:28
void XLogRegisterData(char *data, uint32 len)
Definition: xloginsert.c:364
static XLogRecData * mainrdata_head
Definition: xloginsert.c:98
void XLogRegisterBlock(uint8 block_id, RelFileLocator *rlocator, ForkNumber forknum, BlockNumber blknum, Page page, uint8 flags)
Definition: xloginsert.c:309
static int max_registered_buffers
Definition: xloginsert.c:90
XLogRecPtr XLogInsert(RmgrId rmid, uint8 info)
Definition: xloginsert.c:474
static uint8 curinsert_flags
Definition: xloginsert.c:103
bool XLogCheckBufferNeedsBackup(Buffer buffer)
Definition: xloginsert.c:1027
static uint64 mainrdata_len
Definition: xloginsert.c:100
XLogRecPtr XLogSaveBufferForHint(Buffer buffer, bool buffer_std)
Definition: xloginsert.c:1065
static bool begininsert_called
Definition: xloginsert.c:132
static int max_registered_block_id
Definition: xloginsert.c:91
XLogRecPtr log_newpage(RelFileLocator *rlocator, ForkNumber forknum, BlockNumber blkno, Page page, bool page_std)
Definition: xloginsert.c:1143
void InitXLogInsert(void)
Definition: xloginsert.c:1348
void XLogSetRecordFlags(uint8 flags)
Definition: xloginsert.c:456
static int num_rdatas
Definition: xloginsert.c:129
void log_newpages(RelFileLocator *rlocator, ForkNumber forknum, int num_pages, BlockNumber *blknos, Page *pages, bool page_std)
Definition: xloginsert.c:1175
void XLogRegisterBufData(uint8 block_id, char *data, uint32 len)
Definition: xloginsert.c:405
static XLogRecData * mainrdata_last
Definition: xloginsert.c:99
static MemoryContext xloginsert_cxt
Definition: xloginsert.c:135
void log_newpage_range(Relation rel, ForkNumber forknum, BlockNumber startblk, BlockNumber endblk, bool page_std)
Definition: xloginsert.c:1270
void XLogResetInsertion(void)
Definition: xloginsert.c:222
XLogRecPtr log_newpage_buffer(Buffer buffer, bool page_std)
Definition: xloginsert.c:1237
static XLogRecData hdr_rdt
Definition: xloginsert.c:113
void XLogRegisterBuffer(uint8 block_id, Buffer buffer, uint8 flags)
Definition: xloginsert.c:242
static XLogRecData * XLogRecordAssemble(RmgrId rmid, uint8 info, XLogRecPtr RedoRecPtr, bool doPageWrites, XLogRecPtr *fpw_lsn, int *num_fpi, bool *topxid_included)
Definition: xloginsert.c:548
static char * hdr_scratch
Definition: xloginsert.c:114
static XLogRecData * rdatas
Definition: xloginsert.c:128
void XLogBeginInsert(void)
Definition: xloginsert.c:149
void XLogEnsureRecordSpace(int max_block_id, int ndatas)
Definition: xloginsert.c:175
#define COMPRESS_BUFSIZE
Definition: xloginsert.c:62
static registered_buffer * registered_buffers
Definition: xloginsert.c:89
static bool XLogCompressBackupBlock(char *page, uint16 hole_offset, uint16 hole_length, char *dest, uint16 *dlen)
Definition: xloginsert.c:944
static int max_rdatas
Definition: xloginsert.c:130
#define HEADER_SCRATCH_SIZE
Definition: xloginsert.c:119
#define REGBUF_NO_CHANGE
Definition: xloginsert.h:36
#define REGBUF_STANDARD
Definition: xloginsert.h:34
#define XLR_NORMAL_MAX_BLOCK_ID
Definition: xloginsert.h:27
#define REGBUF_FORCE_IMAGE
Definition: xloginsert.h:31
#define XLR_NORMAL_RDATAS
Definition: xloginsert.h:28
#define REGBUF_NO_IMAGE
Definition: xloginsert.h:32
#define REGBUF_KEEP_DATA
Definition: xloginsert.h:35
#define REGBUF_WILL_INIT
Definition: xloginsert.h:33
size_t DecodeXLogRecordRequiredSpace(size_t xl_tot_len)
Definition: xlogreader.c:1629
#define SizeOfXLogRecordBlockImageHeader
Definition: xlogrecord.h:153
#define XLogRecordMaxSize
Definition: xlogrecord.h:74
#define BKPIMAGE_COMPRESS_ZSTD
Definition: xlogrecord.h:162
#define BKPBLOCK_HAS_DATA
Definition: xlogrecord.h:198
#define BKPIMAGE_APPLY
Definition: xlogrecord.h:158
#define BKPIMAGE_HAS_HOLE
Definition: xlogrecord.h:157
#define XLR_BLOCK_ID_DATA_LONG
Definition: xlogrecord.h:242
#define BKPBLOCK_WILL_INIT
Definition: xlogrecord.h:199
#define XLR_RMGR_INFO_MASK
Definition: xlogrecord.h:63
#define BKPIMAGE_COMPRESS_LZ4
Definition: xlogrecord.h:161
#define XLR_BLOCK_ID_TOPLEVEL_XID
Definition: xlogrecord.h:244
#define XLR_BLOCK_ID_DATA_SHORT
Definition: xlogrecord.h:241
#define XLR_MAX_BLOCK_ID
Definition: xlogrecord.h:239
#define SizeOfXLogRecordBlockCompressHeader
Definition: xlogrecord.h:177
#define BKPBLOCK_SAME_REL
Definition: xlogrecord.h:200
#define XLR_SPECIAL_REL_UPDATE
Definition: xlogrecord.h:82
#define SizeOfXLogRecordBlockHeader
Definition: xlogrecord.h:115
#define BKPIMAGE_COMPRESS_PGLZ
Definition: xlogrecord.h:160
#define XLR_BLOCK_ID_ORIGIN
Definition: xlogrecord.h:243
#define SizeOfXLogRecord
Definition: xlogrecord.h:55
#define BKPBLOCK_HAS_IMAGE
Definition: xlogrecord.h:197
#define XLR_CHECK_CONSISTENCY
Definition: xlogrecord.h:91