-
Notifications
You must be signed in to change notification settings - Fork 3.7k
/
mtr0mtr.h
710 lines (556 loc) · 23.5 KB
/
mtr0mtr.h
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
/*****************************************************************************
Copyright (c) 1995, 2022, Oracle and/or its affiliates.
Copyright (c) 2012, Facebook Inc.
This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License, version 2.0, as published by the
Free Software Foundation.
This program is also distributed with certain software (including but not
limited to OpenSSL) that is licensed under separate terms, as designated in a
particular file or component or in included license documentation. The authors
of MySQL hereby grant you an additional permission to link the program and
your derivative works with the separately licensed software that they have
included with MySQL.
This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU General Public License, version 2.0,
for more details.
You should have received a copy of the GNU General Public License along with
this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*****************************************************************************/
/** @file include/mtr0mtr.h
Mini-transaction buffer
Created 11/26/1995 Heikki Tuuri
*******************************************************/
#ifndef mtr0mtr_h
#define mtr0mtr_h
#include <stddef.h>
#include "univ.i"
#include "buf0types.h"
#include "dyn0buf.h"
#include "fil0fil.h"
#include "mtr0types.h"
#include "srv0srv.h"
#include "trx0types.h"
/** Start a mini-transaction. */
#define mtr_start(m) (m)->start()
/** Start a synchronous mini-transaction */
#define mtr_start_sync(m) (m)->start(true)
/** Start an asynchronous read-only mini-transaction */
#define mtr_start_ro(m) (m)->start(true, true)
/** Commit a mini-transaction. */
#define mtr_commit(m) (m)->commit()
/** Set and return a savepoint in mtr.
@return savepoint */
#define mtr_set_savepoint(m) (m)->get_savepoint()
/** Release the (index tree) s-latch stored in an mtr memo after a
savepoint. */
#define mtr_release_s_latch_at_savepoint(m, s, l) \
(m)->release_s_latch_at_savepoint((s), (l))
/** Get the logging mode of a mini-transaction.
@return logging mode: MTR_LOG_NONE, ... */
#define mtr_get_log_mode(m) (m)->get_log_mode()
/** Change the logging mode of a mini-transaction.
@return old mode */
#define mtr_set_log_mode(m, d) (m)->set_log_mode((d))
/** Get the flush observer of a mini-transaction.
@return flush observer object */
#define mtr_get_flush_observer(m) (m)->get_flush_observer()
/** Set the flush observer of a mini-transaction. */
#define mtr_set_flush_observer(m, d) (m)->set_flush_observer((d))
/** Read 1 - 4 bytes from a file page buffered in the buffer pool.
@return value read */
#define mtr_read_ulint(p, t, m) (m)->read_ulint((p), (t))
/** Release an object in the memo stack.
@return true if released */
#define mtr_memo_release(m, o, t) (m)->memo_release((o), (t))
#ifdef UNIV_DEBUG
/** Check if memo contains the given item ignore if table is intrinsic
@return true if contains or table is intrinsic. */
#define mtr_is_block_fix(m, o, t, table) \
(mtr_memo_contains(m, o, t) || table->is_intrinsic())
/** Check if memo contains the given page ignore if table is intrinsic
@return true if contains or table is intrinsic. */
#define mtr_is_page_fix(m, p, t, table) \
(mtr_memo_contains_page(m, p, t) || table->is_intrinsic())
/** Check if memo contains the given item.
@return true if contains */
#define mtr_memo_contains(m, o, t) (m)->memo_contains((m)->get_memo(), (o), (t))
/** Check if memo contains the given page.
@return true if contains */
#define mtr_memo_contains_page(m, p, t) \
(m)->memo_contains_page_flagged((p), (t))
#endif /* UNIV_DEBUG */
/** Print info of an mtr handle. */
#define mtr_print(m) (m)->print()
/** Return the log object of a mini-transaction buffer.
@return log */
#define mtr_get_log(m) (m)->get_log()
/** Push an object to an mtr memo stack. */
#define mtr_memo_push(m, o, t) (m)->memo_push(o, t)
/** Lock an rw-lock in s-mode. */
#define mtr_s_lock(l, m, loc) (m)->s_lock((l), loc)
/** Lock an rw-lock in x-mode. */
#define mtr_x_lock(l, m, loc) (m)->x_lock((l), loc)
/** Lock a tablespace in x-mode. */
#define mtr_x_lock_space(s, m) (m)->x_lock_space((s), UT_LOCATION_HERE)
/** Lock an rw-lock in sx-mode. */
#define mtr_sx_lock(l, m, loc) (m)->sx_lock((l), loc)
#define mtr_memo_contains_flagged(m, p, l) (m)->memo_contains_flagged((p), (l))
#define mtr_memo_contains_page_flagged(m, p, l) \
(m)->memo_contains_page_flagged((p), (l))
#define mtr_release_block_at_savepoint(m, s, b) \
(m)->release_block_at_savepoint((s), (b))
#define mtr_block_sx_latch_at_savepoint(m, s, b) \
(m)->sx_latch_at_savepoint((s), (b))
#define mtr_block_x_latch_at_savepoint(m, s, b) \
(m)->x_latch_at_savepoint((s), (b))
/** Check if a mini-transaction is dirtying a clean page.
@param b block being x-fixed
@return true if the mtr is dirtying a clean page. */
#define mtr_block_dirtied(b) mtr_t::is_block_dirtied((b))
/** Forward declaration of a tablespace object */
struct fil_space_t;
/** Mini-transaction memo stack slot. */
struct mtr_memo_slot_t {
/** Pointer to the object - either buf_block_t or rw_lock_t */
void *object;
/** type of the stored object (MTR_MEMO_S_LOCK, ...) */
ulint type;
/** Check if the object stored in this slot is a lock (rw_lock_t).
@return true if it is a lock object, false otherwise. */
bool is_lock() const {
return type == MTR_MEMO_S_LOCK || type == MTR_MEMO_X_LOCK ||
type == MTR_MEMO_SX_LOCK;
}
std::ostream &print(std::ostream &out) const;
};
inline std::ostream &operator<<(std::ostream &out, const mtr_memo_slot_t &obj) {
return obj.print(out);
}
/** Mini-transaction handle and buffer */
struct mtr_t {
/** State variables of the mtr */
struct Impl {
/** memo stack for locks etc. */
mtr_buf_t m_memo;
/** mini-transaction log */
mtr_buf_t m_log;
/** true if mtr has made at least one buffer pool page dirty */
bool m_made_dirty;
/** true if inside ibuf changes */
bool m_inside_ibuf;
/** true if the mini-transaction modified buffer pool pages */
bool m_modifications;
/** true if mtr is forced to NO_LOG mode because redo logging is
disabled globally. In this case, mtr increments the global counter
at ::start and must decrement it back at ::commit. */
bool m_marked_nolog;
/** Shard index used for incrementing global counter at ::start. We need
to use the same shard while decrementing counter at ::commit. */
size_t m_shard_index;
/** Count of how many page initial log records have been
written to the mtr log */
uint32_t m_n_log_recs;
/** specifies which operations should be logged; default
value MTR_LOG_ALL */
mtr_log_t m_log_mode;
/** State of the transaction */
mtr_state_t m_state;
/** Flush Observer */
Flush_observer *m_flush_observer;
#ifdef UNIV_DEBUG
/** For checking corruption. */
ulint m_magic_n;
#endif /* UNIV_DEBUG */
/** Owning mini-transaction */
mtr_t *m_mtr;
};
#ifndef UNIV_HOTBACKUP
/** mtr global logging */
class Logging {
public:
/** mtr global redo logging state.
Enable Logging :
[ENABLED] -> [ENABLED_RESTRICT] -> [DISABLED]
Disable Logging :
[DISABLED] -> [ENABLED_RESTRICT] -> [ENABLED_DBLWR] -> [ENABLED] */
enum State : uint32_t {
/* Redo Logging is enabled. Server is crash safe. */
ENABLED,
/* Redo logging is enabled. All non-logging mtr are finished with the
pages flushed to disk. Double write is enabled. Some pages could be
still getting written to disk without double-write. Not safe to crash. */
ENABLED_DBLWR,
/* Redo logging is enabled but there could be some mtrs still running
in no logging mode. Redo archiving and clone are not allowed to start.
No double-write */
ENABLED_RESTRICT,
/* Redo logging is disabled and all new mtrs would not generate any redo.
Redo archiving and clone are not allowed. */
DISABLED
};
/** Initialize logging state at server start up. */
void init() {
m_state.store(ENABLED);
/* We use sharded counter and force sequentially consistent counting
which is the general default for c++ atomic operation. If we try to
optimize it further specific to current operations, we could use
Release-Acquire ordering i.e. std::memory_order_release during counting
and std::memory_order_acquire while checking for the count. However,
sharding looks to be good enough for now and we should go for non default
memory ordering only with some visible proof for improvement. */
m_count_nologging_mtr.set_order(std::memory_order_seq_cst);
Counter::clear(m_count_nologging_mtr);
}
/** Disable mtr redo logging. Server is crash unsafe without logging.
@param[in] thd server connection THD
@return mysql error code. */
int disable(THD *thd);
/** Enable mtr redo logging. Ensure that the server is crash safe
before returning.
@param[in] thd server connection THD
@return mysql error code. */
int enable(THD *thd);
/** Mark a no-logging mtr to indicate that it would not generate redo log
and system is crash unsafe.
@return true iff logging is disabled and mtr is marked. */
bool mark_mtr(size_t index) {
/* Have initial check to avoid incrementing global counter for regular
case when redo logging is enabled. */
if (is_disabled()) {
/* Increment counter to restrict state change DISABLED to ENABLED. */
Counter::inc(m_count_nologging_mtr, index);
/* Check if the no-logging is still disabled. At this point, if we
find the state disabled, it is no longer possible for the state move
back to enabled till the mtr finishes and we unmark the mtr. */
if (is_disabled()) {
return (true);
}
Counter::dec(m_count_nologging_mtr, index);
}
return (false);
}
/** unmark a no logging mtr. */
void unmark_mtr(size_t index) {
ut_ad(!is_enabled());
ut_ad(Counter::total(m_count_nologging_mtr) > 0);
Counter::dec(m_count_nologging_mtr, index);
}
/* @return flush loop count for faster response when logging is disabled. */
uint32_t get_nolog_flush_loop() const { return (NOLOG_MAX_FLUSH_LOOP); }
/** @return true iff redo logging is enabled and server is crash safe. */
bool is_enabled() const { return (m_state.load() == ENABLED); }
/** @return true iff redo logging is disabled and new mtrs are not going
to generate redo log. */
bool is_disabled() const { return (m_state.load() == DISABLED); }
/** @return true iff we can skip data page double write. */
bool dblwr_disabled() const {
auto state = m_state.load();
return (state == DISABLED || state == ENABLED_RESTRICT);
}
/* Force faster flush loop for quicker adaptive flush response when logging
is disabled. When redo logging is disabled the system operates faster with
dirty pages generated at much faster rate. */
static constexpr uint32_t NOLOG_MAX_FLUSH_LOOP = 5;
private:
/** Wait till all no-logging mtrs are finished.
@return mysql error code. */
int wait_no_log_mtr(THD *thd);
private:
/** Global redo logging state. */
std::atomic<State> m_state;
using Shards = Counter::Shards<128>;
/** Number of no logging mtrs currently running. */
Shards m_count_nologging_mtr;
};
/** Check if redo logging is disabled globally and mark
the global counter till mtr ends. */
void check_nolog_and_mark();
/** Check if the mtr has marked the global no log counter and
unmark it. */
void check_nolog_and_unmark();
#endif /* !UNIV_HOTBACKUP */
mtr_t() {
m_impl.m_state = MTR_STATE_INIT;
m_impl.m_marked_nolog = false;
m_impl.m_shard_index = 0;
}
~mtr_t() {
#ifdef UNIV_DEBUG
switch (m_impl.m_state) {
case MTR_STATE_ACTIVE:
ut_ad(m_impl.m_memo.size() == 0);
ut_d(remove_from_debug_list());
break;
case MTR_STATE_INIT:
case MTR_STATE_COMMITTED:
break;
case MTR_STATE_COMMITTING:
ut_error;
}
#endif /* UNIV_DEBUG */
#ifndef UNIV_HOTBACKUP
/* Safety check in case mtr is not committed. */
if (m_impl.m_state != MTR_STATE_INIT) {
check_nolog_and_unmark();
}
#endif /* !UNIV_HOTBACKUP */
}
#ifdef UNIV_DEBUG
/** Removed the MTR from the s_my_thread_active_mtrs list. */
void remove_from_debug_list() const;
/** Assure that there are no slots that are latching any resources. Only
buffer fixing a page is allowed. */
void check_is_not_latching() const;
#endif /* UNIV_DEBUG */
/** Start a mini-transaction.
@param sync true if it is a synchronous mini-transaction */
void start(bool sync = true);
/** @return whether this is an asynchronous mini-transaction. */
bool is_async() const { return (!m_sync); }
/** Request a future commit to be synchronous. */
void set_sync() { m_sync = true; }
/** Commit the mini-transaction. */
void commit();
/** Return current size of the buffer.
@return savepoint */
[[nodiscard]] ulint get_savepoint() const {
ut_ad(is_active());
ut_ad(m_impl.m_magic_n == MTR_MAGIC_N);
return (m_impl.m_memo.size());
}
/** Release the (index tree) s-latch stored in an mtr memo after a
savepoint.
@param savepoint value returned by @see set_savepoint.
@param lock latch to release */
inline void release_s_latch_at_savepoint(ulint savepoint, rw_lock_t *lock);
/** Release the block in an mtr memo after a savepoint. */
inline void release_block_at_savepoint(ulint savepoint, buf_block_t *block);
/** SX-latch a not yet latched block after a savepoint. */
inline void sx_latch_at_savepoint(ulint savepoint, buf_block_t *block);
/** X-latch a not yet latched block after a savepoint. */
inline void x_latch_at_savepoint(ulint savepoint, buf_block_t *block);
/** Get the logging mode.
@return logging mode */
[[nodiscard]] inline mtr_log_t get_log_mode() const;
/** Change the logging mode.
@param mode logging mode
@return old mode */
mtr_log_t set_log_mode(mtr_log_t mode);
/** Read 1 - 4 bytes from a file page buffered in the buffer pool.
@param ptr pointer from where to read
@param type MLOG_1BYTE, MLOG_2BYTES, MLOG_4BYTES
@return value read */
[[nodiscard]] inline uint32_t read_ulint(const byte *ptr,
mlog_id_t type) const;
/** Locks a rw-latch in S mode.
NOTE: use mtr_s_lock().
@param lock rw-lock
@param location location from where called */
inline void s_lock(rw_lock_t *lock, ut::Location location);
/** Locks a rw-latch in X mode.
NOTE: use mtr_x_lock().
@param lock rw-lock
@param location location where name from where called */
inline void x_lock(rw_lock_t *lock, ut::Location location);
/** Locks a rw-latch in X mode.
NOTE: use mtr_sx_lock().
@param lock rw-lock
@param location location from where called */
inline void sx_lock(rw_lock_t *lock, ut::Location location);
/** Acquire a tablespace X-latch.
NOTE: use mtr_x_lock_space().
@param[in] space tablespace instance
@param[in] location location from where called */
void x_lock_space(fil_space_t *space, ut::Location location);
/** Release an object in the memo stack.
@param object object
@param type object type: MTR_MEMO_S_LOCK, ... */
void memo_release(const void *object, ulint type);
/** Release a page latch.
@param[in] ptr pointer to within a page frame
@param[in] type object type: MTR_MEMO_PAGE_X_FIX, ... */
void release_page(const void *ptr, mtr_memo_type_t type);
/** Note that the mini-transaction has modified data. */
void set_modified() { m_impl.m_modifications = true; }
/** Set the state to not-modified. This will not log the
changes. This is only used during redo log apply, to avoid
logging the changes. */
void discard_modifications() { m_impl.m_modifications = false; }
/** Get the LSN of commit().
@return the commit LSN
@retval 0 if the transaction only modified temporary tablespaces or logging
is disabled globally. */
[[nodiscard]] lsn_t commit_lsn() const {
ut_ad(has_committed());
ut_ad(m_impl.m_log_mode == MTR_LOG_ALL);
return (m_commit_lsn);
}
/** Note that we are inside the change buffer code. */
void enter_ibuf() { m_impl.m_inside_ibuf = true; }
/** Note that we have exited from the change buffer code. */
void exit_ibuf() { m_impl.m_inside_ibuf = false; }
/** @return true if we are inside the change buffer code */
[[nodiscard]] bool is_inside_ibuf() const { return (m_impl.m_inside_ibuf); }
/*
@return true if the mini-transaction is active */
[[nodiscard]] bool is_active() const {
return (m_impl.m_state == MTR_STATE_ACTIVE);
}
/** Get flush observer
@return flush observer */
[[nodiscard]] Flush_observer *get_flush_observer() const {
return (m_impl.m_flush_observer);
}
/** Set flush observer
@param[in] observer flush observer */
void set_flush_observer(Flush_observer *observer) {
ut_ad(observer == nullptr || m_impl.m_log_mode == MTR_LOG_NO_REDO);
m_impl.m_flush_observer = observer;
}
/** Print the memo objects (mtr_memo_slot_t) of mtr_t to the given output
stream.
@param[in] out the output stream for printing
@return the output stream. */
std::ostream &print_memos(std::ostream &out) const;
#ifdef UNIV_DEBUG
/** Check if memo contains the given item.
@param memo memo stack
@param object object to search
@param type type of object
@return true if contains */
[[nodiscard]] static bool memo_contains(const mtr_buf_t *memo,
const void *object, ulint type);
/** Check if memo contains the given item.
@param ptr object to search
@param flags specify types of object (can be ORred) of
MTR_MEMO_PAGE_S_FIX ... values
@return true if contains */
[[nodiscard]] bool memo_contains_flagged(const void *ptr, ulint flags) const;
/** Check if memo contains the given page.
@param[in] ptr pointer to within buffer frame
@param[in] flags specify types of object with OR of
MTR_MEMO_PAGE_S_FIX... values
@return the block
@retval NULL if not found */
[[nodiscard]] buf_block_t *memo_contains_page_flagged(const byte *ptr,
ulint flags) const;
/** Mark the given latched page as modified.
@param[in] ptr pointer to within buffer frame */
void memo_modify_page(const byte *ptr);
/** Print info of an mtr handle. */
void print() const;
/** @return true if the mini-transaction has committed */
[[nodiscard]] bool has_committed() const {
return (m_impl.m_state == MTR_STATE_COMMITTED);
}
/** @return true if the mini-transaction is committing */
bool is_committing() const {
return (m_impl.m_state == MTR_STATE_COMMITTING);
}
/** @return true if mini-transaction contains modifications. */
[[nodiscard]] bool has_modifications() const {
return (m_impl.m_modifications);
}
/** Check if the changes done in this mtr conflicts with changes done
in the given mtr. Two mtrs are said to conflict with each other, if
they modify the same buffer block.
@param[in] mtr2 the given mtr.
@return true if there is conflict, false otherwise. */
[[nodiscard]] bool conflicts_with(const mtr_t *mtr2) const;
/** @return the memo stack */
[[nodiscard]] const mtr_buf_t *get_memo() const { return (&m_impl.m_memo); }
/** @return the memo stack */
[[nodiscard]] mtr_buf_t *get_memo() { return (&m_impl.m_memo); }
/** Computes the number of bytes that would be written to the redo
log if mtr was committed right now (excluding headers of log blocks).
@return number of bytes of the collected log records increased
by 1 if MLOG_MULTI_REC_END would already be required */
size_t get_expected_log_size() const {
return (m_impl.m_log.size() + (m_impl.m_n_log_recs > 1 ? 1 : 0));
}
void wait_for_flush();
#endif /* UNIV_DEBUG */
/** @return true if a record was added to the mini-transaction */
[[nodiscard]] bool is_dirty() const { return (m_impl.m_made_dirty); }
/** Note that a record has been added to the log */
void added_rec() { ++m_impl.m_n_log_recs; }
/** Get the buffered redo log of this mini-transaction.
@return redo log */
[[nodiscard]] const mtr_buf_t *get_log() const {
ut_ad(m_impl.m_magic_n == MTR_MAGIC_N);
return (&m_impl.m_log);
}
/** Get the buffered redo log of this mini-transaction.
@return redo log */
[[nodiscard]] mtr_buf_t *get_log() {
ut_ad(m_impl.m_magic_n == MTR_MAGIC_N);
return (&m_impl.m_log);
}
/** Push an object to an mtr memo stack.
@param object object
@param type object type: MTR_MEMO_S_LOCK, ... */
inline void memo_push(void *object, mtr_memo_type_t type);
#ifdef UNIV_DEBUG
/** Iterate all MTRs created in this thread to assure they are not latching
any resources. Violating this could lead to deadlocks under
log_free_check(). */
static void check_my_thread_mtrs_are_not_latching() {
for (auto &it : s_my_thread_active_mtrs) {
it->check_is_not_latching();
}
}
#endif
/** Check if this mini-transaction is dirtying a clean page.
@param block block being x-fixed
@return true if the mtr is dirtying a clean page. */
[[nodiscard]] static bool is_block_dirtied(const buf_block_t *block);
/** Matrix to check if a mode update request should be ignored. */
static bool s_mode_update[MTR_LOG_MODE_MAX][MTR_LOG_MODE_MAX];
#ifdef UNIV_DEBUG
/** For checking invalid mode update requests. */
static bool s_mode_update_valid[MTR_LOG_MODE_MAX][MTR_LOG_MODE_MAX];
/** Count the number of times the same mtr object has been committed and
restarted. */
size_t m_restart_count{};
#endif /* UNIV_DEBUG */
#ifndef UNIV_HOTBACKUP
/** Instance level logging information for all mtrs. */
static Logging s_logging;
#endif /* !UNIV_HOTBACKUP */
private:
Impl m_impl;
/** LSN at commit time */
lsn_t m_commit_lsn;
/** true if it is synchronous mini-transaction */
bool m_sync;
#ifdef UNIV_DEBUG
/** List of all non-committed MTR instances created in this thread. Used for
debug purposes in the log_free_check(). */
static thread_local ut::unordered_set<const mtr_t *> s_my_thread_active_mtrs;
#endif
class Command;
friend class Command;
};
#ifndef UNIV_HOTBACKUP
#ifdef UNIV_DEBUG
/** Reserves space in the log buffer and writes a single MLOG_TEST.
@param[in] payload number of extra bytes within the record,
not greater than 1024
@return end_lsn pointing to the first byte after the written record */
lsn_t mtr_commit_mlog_test(size_t payload = 0);
/** Reserves space in the log buffer and writes a single MLOG_TEST.
Adjusts size of the payload in the record, in order to fill the current
block up to its boundary. If nothing else is happening in parallel,
we could expect to see afterwards:
(cur_lsn + space_left) % OS_FILE_LOG_BLOCK_SIZE == LOG_BLOCK_HDR_SIZE,
where cur_lsn = log_get_lsn(log).
@param[in,out] log redo log
@param[in] space_left extra bytes left to the boundary of block,
must be not greater than 496 */
void mtr_commit_mlog_test_filling_block(log_t &log, size_t space_left = 0);
#endif /* UNIV_DEBUG */
#endif /* !UNIV_HOTBACKUP */
#include "mtr0mtr.ic"
#endif /* mtr0mtr_h */