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Merge Stewart - fix bug 587772: READ COMMITTED isolation level doesn't work (at least with InnoDB)

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1
/*****************************************************************************
2
2
 
3
 
Copyright (c) 1995, 2010, Innobase Oy. All Rights Reserved.
 
3
Copyright (c) 1995, 2009, Innobase Oy. All Rights Reserved.
4
4
 
5
5
This program is free software; you can redistribute it and/or modify it under
6
6
the terms of the GNU General Public License as published by the Free Software
83
83
@return TRUE if ok */
84
84
static
85
85
ibool
86
 
buf_flush_validate_low(
87
 
/*===================*/
88
 
        buf_pool_t*     buf_pool);      /*!< in: Buffer pool instance */
89
 
#endif /* UNIV_DEBUG || UNIV_BUF_DEBUG */
90
 
 
91
 
/******************************************************************//**
92
 
Insert a block in the flush_rbt and returns a pointer to its
93
 
predecessor or NULL if no predecessor. The ordering is maintained
94
 
on the basis of the <oldest_modification, space, offset> key.
95
 
@return pointer to the predecessor or NULL if no predecessor. */
96
 
static
97
 
buf_page_t*
98
 
buf_flush_insert_in_flush_rbt(
99
 
/*==========================*/
100
 
        buf_page_t*     bpage)  /*!< in: bpage to be inserted. */
101
 
{
102
 
        const ib_rbt_node_t*    c_node;
103
 
        const ib_rbt_node_t*    p_node;
104
 
        buf_page_t*             prev = NULL;
105
 
        buf_pool_t*             buf_pool = buf_pool_from_bpage(bpage);
106
 
 
107
 
        ut_ad(buf_flush_list_mutex_own(buf_pool));
108
 
 
109
 
        /* Insert this buffer into the rbt. */
110
 
        c_node = rbt_insert(buf_pool->flush_rbt, &bpage, &bpage);
111
 
        ut_a(c_node != NULL);
112
 
 
113
 
        /* Get the predecessor. */
114
 
        p_node = rbt_prev(buf_pool->flush_rbt, c_node);
115
 
 
116
 
        if (p_node != NULL) {
117
 
                buf_page_t**    value;
118
 
                value = rbt_value(buf_page_t*, p_node);
119
 
                prev = *value;
120
 
                ut_a(prev != NULL);
121
 
        }
122
 
 
123
 
        return(prev);
124
 
}
125
 
 
126
 
/*********************************************************//**
127
 
Delete a bpage from the flush_rbt. */
128
 
static
129
 
void
130
 
buf_flush_delete_from_flush_rbt(
131
 
/*============================*/
132
 
        buf_page_t*     bpage)  /*!< in: bpage to be removed. */
133
 
{
134
 
#ifdef UNIV_DEBUG
135
 
        ibool           ret = FALSE;
136
 
#endif /* UNIV_DEBUG */
137
 
        buf_pool_t*     buf_pool = buf_pool_from_bpage(bpage);
138
 
 
139
 
        ut_ad(buf_flush_list_mutex_own(buf_pool));
140
 
 
141
 
#ifdef UNIV_DEBUG
142
 
        ret =
143
 
#endif /* UNIV_DEBUG */
144
 
        rbt_delete(buf_pool->flush_rbt, &bpage);
145
 
        ut_ad(ret);
146
 
}
147
 
 
148
 
/*****************************************************************//**
149
 
Compare two modified blocks in the buffer pool. The key for comparison
150
 
is:
151
 
key = <oldest_modification, space, offset>
152
 
This comparison is used to maintian ordering of blocks in the
153
 
buf_pool->flush_rbt.
154
 
Note that for the purpose of flush_rbt, we only need to order blocks
155
 
on the oldest_modification. The other two fields are used to uniquely
156
 
identify the blocks.
157
 
@return  < 0 if b2 < b1, 0 if b2 == b1, > 0 if b2 > b1 */
158
 
static
159
 
int
160
 
buf_flush_block_cmp(
161
 
/*================*/
162
 
        const void*     p1,             /*!< in: block1 */
163
 
        const void*     p2)             /*!< in: block2 */
164
 
{
165
 
        int                     ret;
166
 
        const buf_page_t*       b1 = *(const buf_page_t**) p1;
167
 
        const buf_page_t*       b2 = *(const buf_page_t**) p2;
168
 
#ifdef UNIV_DEBUG
169
 
        buf_pool_t*             buf_pool = buf_pool_from_bpage(b1);
170
 
#endif /* UNIV_DEBUG */
171
 
 
172
 
        ut_ad(b1 != NULL);
173
 
        ut_ad(b2 != NULL);
174
 
 
175
 
        ut_ad(buf_flush_list_mutex_own(buf_pool));
176
 
 
177
 
        ut_ad(b1->in_flush_list);
178
 
        ut_ad(b2->in_flush_list);
179
 
 
180
 
        if (b2->oldest_modification > b1->oldest_modification) {
181
 
                return(1);
182
 
        } else if (b2->oldest_modification < b1->oldest_modification) {
183
 
                return(-1);
184
 
        }
185
 
 
186
 
        /* If oldest_modification is same then decide on the space. */
187
 
        ret = (int)(b2->space - b1->space);
188
 
 
189
 
        /* Or else decide ordering on the offset field. */
190
 
        return(ret ? ret : (int)(b2->offset - b1->offset));
191
 
}
192
 
 
193
 
/********************************************************************//**
194
 
Initialize the red-black tree to speed up insertions into the flush_list
195
 
during recovery process. Should be called at the start of recovery
196
 
process before any page has been read/written. */
197
 
UNIV_INTERN
198
 
void
199
 
buf_flush_init_flush_rbt(void)
200
 
/*==========================*/
201
 
{
202
 
        ulint   i;
203
 
 
204
 
        for (i = 0; i < srv_buf_pool_instances; i++) {
205
 
                buf_pool_t*     buf_pool;
206
 
 
207
 
                buf_pool = buf_pool_from_array(i);
208
 
 
209
 
                buf_flush_list_mutex_enter(buf_pool);
210
 
 
211
 
                /* Create red black tree for speedy insertions in flush list. */
212
 
                buf_pool->flush_rbt = rbt_create(
213
 
                        sizeof(buf_page_t*), buf_flush_block_cmp);
214
 
 
215
 
                buf_flush_list_mutex_exit(buf_pool);
216
 
        }
217
 
}
218
 
 
219
 
/********************************************************************//**
220
 
Frees up the red-black tree. */
221
 
UNIV_INTERN
222
 
void
223
 
buf_flush_free_flush_rbt(void)
224
 
/*==========================*/
225
 
{
226
 
        ulint   i;
227
 
 
228
 
        for (i = 0; i < srv_buf_pool_instances; i++) {
229
 
                buf_pool_t*     buf_pool;
230
 
 
231
 
                buf_pool = buf_pool_from_array(i);
232
 
 
233
 
                buf_flush_list_mutex_enter(buf_pool);
234
 
 
235
 
#ifdef UNIV_DEBUG_VALGRIND
236
 
        {
237
 
                ulint   zip_size = buf_block_get_zip_size(block);
238
 
 
239
 
                if (UNIV_UNLIKELY(zip_size)) {
240
 
                        UNIV_MEM_ASSERT_RW(block->page.zip.data, zip_size);
241
 
                } else {
242
 
                        UNIV_MEM_ASSERT_RW(block->frame, UNIV_PAGE_SIZE);
243
 
                }
244
 
        }
245
 
#endif /* UNIV_DEBUG_VALGRIND */
246
 
#if defined UNIV_DEBUG || defined UNIV_BUF_DEBUG
247
 
                ut_a(buf_flush_validate_low(buf_pool));
248
 
#endif /* UNIV_DEBUG || UNIV_BUF_DEBUG */
249
 
 
250
 
                rbt_free(buf_pool->flush_rbt);
251
 
                buf_pool->flush_rbt = NULL;
252
 
 
253
 
                buf_flush_list_mutex_exit(buf_pool);
254
 
        }
255
 
}
 
86
buf_flush_validate_low(void);
 
87
/*========================*/
 
88
#endif /* UNIV_DEBUG || UNIV_BUF_DEBUG */
256
89
 
257
90
/********************************************************************//**
258
91
Inserts a modified block into the flush list. */
260
93
void
261
94
buf_flush_insert_into_flush_list(
262
95
/*=============================*/
263
 
        buf_pool_t*     buf_pool,       /*!< buffer pool instance */
264
 
        buf_block_t*    block,          /*!< in/out: block which is modified */
265
 
        ib_uint64_t     lsn)            /*!< in: oldest modification */
 
96
        buf_block_t*    block)  /*!< in/out: block which is modified */
266
97
{
267
 
        ut_ad(!buf_pool_mutex_own(buf_pool));
268
 
        ut_ad(log_flush_order_mutex_own());
269
 
        ut_ad(mutex_own(&block->mutex));
270
 
 
271
 
        buf_flush_list_mutex_enter(buf_pool);
272
 
 
 
98
        ut_ad(buf_pool_mutex_own());
273
99
        ut_ad((UT_LIST_GET_FIRST(buf_pool->flush_list) == NULL)
274
100
              || (UT_LIST_GET_FIRST(buf_pool->flush_list)->oldest_modification
275
 
                  <= lsn));
276
 
 
277
 
        /* If we are in the recovery then we need to update the flush
278
 
        red-black tree as well. */
279
 
        if (UNIV_LIKELY_NULL(buf_pool->flush_rbt)) {
280
 
                buf_flush_list_mutex_exit(buf_pool);
281
 
                buf_flush_insert_sorted_into_flush_list(buf_pool, block, lsn);
282
 
                return;
283
 
        }
 
101
                  <= block->page.oldest_modification));
284
102
 
285
103
        ut_ad(buf_block_get_state(block) == BUF_BLOCK_FILE_PAGE);
 
104
        ut_ad(block->page.in_LRU_list);
 
105
        ut_ad(block->page.in_page_hash);
 
106
        ut_ad(!block->page.in_zip_hash);
286
107
        ut_ad(!block->page.in_flush_list);
287
 
 
288
108
        ut_d(block->page.in_flush_list = TRUE);
289
 
        block->page.oldest_modification = lsn;
290
109
        UT_LIST_ADD_FIRST(list, buf_pool->flush_list, &block->page);
291
110
 
292
 
#ifdef UNIV_DEBUG_VALGRIND
293
 
        {
294
 
                ulint   zip_size = buf_block_get_zip_size(block);
295
 
 
296
 
                if (UNIV_UNLIKELY(zip_size)) {
297
 
                        UNIV_MEM_ASSERT_RW(block->page.zip.data, zip_size);
298
 
                } else {
299
 
                        UNIV_MEM_ASSERT_RW(block->frame, UNIV_PAGE_SIZE);
300
 
                }
301
 
        }
302
 
#endif /* UNIV_DEBUG_VALGRIND */
303
111
#if defined UNIV_DEBUG || defined UNIV_BUF_DEBUG
304
 
        ut_a(buf_flush_validate_low(buf_pool));
 
112
        ut_a(buf_flush_validate_low());
305
113
#endif /* UNIV_DEBUG || UNIV_BUF_DEBUG */
306
 
 
307
 
        buf_flush_list_mutex_exit(buf_pool);
308
114
}
309
115
 
310
116
/********************************************************************//**
315
121
void
316
122
buf_flush_insert_sorted_into_flush_list(
317
123
/*====================================*/
318
 
        buf_pool_t*     buf_pool,       /*!< in: buffer pool instance */
319
 
        buf_block_t*    block,          /*!< in/out: block which is modified */
320
 
        ib_uint64_t     lsn)            /*!< in: oldest modification */
 
124
        buf_block_t*    block)  /*!< in/out: block which is modified */
321
125
{
322
126
        buf_page_t*     prev_b;
323
127
        buf_page_t*     b;
324
128
 
325
 
        ut_ad(!buf_pool_mutex_own(buf_pool));
326
 
        ut_ad(log_flush_order_mutex_own());
327
 
        ut_ad(mutex_own(&block->mutex));
 
129
        ut_ad(buf_pool_mutex_own());
328
130
        ut_ad(buf_block_get_state(block) == BUF_BLOCK_FILE_PAGE);
329
131
 
330
 
        buf_flush_list_mutex_enter(buf_pool);
331
 
 
332
 
        /* The field in_LRU_list is protected by buf_pool_mutex, which
333
 
        we are not holding.  However, while a block is in the flush
334
 
        list, it is dirty and cannot be discarded, not from the
335
 
        page_hash or from the LRU list.  At most, the uncompressed
336
 
        page frame of a compressed block may be discarded or created
337
 
        (copying the block->page to or from a buf_page_t that is
338
 
        dynamically allocated from buf_buddy_alloc()).  Because those
339
 
        transitions hold block->mutex and the flush list mutex (via
340
 
        buf_flush_relocate_on_flush_list()), there is no possibility
341
 
        of a race condition in the assertions below. */
342
132
        ut_ad(block->page.in_LRU_list);
343
133
        ut_ad(block->page.in_page_hash);
344
 
        /* buf_buddy_block_register() will take a block in the
345
 
        BUF_BLOCK_MEMORY state, not a file page. */
346
134
        ut_ad(!block->page.in_zip_hash);
347
 
 
348
135
        ut_ad(!block->page.in_flush_list);
349
136
        ut_d(block->page.in_flush_list = TRUE);
350
 
        block->page.oldest_modification = lsn;
351
 
 
352
 
#ifdef UNIV_DEBUG_VALGRIND
353
 
        {
354
 
                ulint   zip_size = buf_block_get_zip_size(block);
355
 
 
356
 
                if (UNIV_UNLIKELY(zip_size)) {
357
 
                        UNIV_MEM_ASSERT_RW(block->page.zip.data, zip_size);
358
 
                } else {
359
 
                        UNIV_MEM_ASSERT_RW(block->frame, UNIV_PAGE_SIZE);
360
 
                }
361
 
        }
362
 
#endif /* UNIV_DEBUG_VALGRIND */
363
 
 
364
 
#ifdef UNIV_DEBUG_VALGRIND
365
 
        {
366
 
                ulint   zip_size = buf_block_get_zip_size(block);
367
 
 
368
 
                if (UNIV_UNLIKELY(zip_size)) {
369
 
                        UNIV_MEM_ASSERT_RW(block->page.zip.data, zip_size);
370
 
                } else {
371
 
                        UNIV_MEM_ASSERT_RW(block->frame, UNIV_PAGE_SIZE);
372
 
                }
373
 
        }
374
 
#endif /* UNIV_DEBUG_VALGRIND */
375
137
 
376
138
        prev_b = NULL;
377
 
 
378
 
        /* For the most part when this function is called the flush_rbt
379
 
        should not be NULL. In a very rare boundary case it is possible
380
 
        that the flush_rbt has already been freed by the recovery thread
381
 
        before the last page was hooked up in the flush_list by the
382
 
        io-handler thread. In that case we'll  just do a simple
383
 
        linear search in the else block. */
384
 
        if (buf_pool->flush_rbt) {
385
 
 
386
 
                prev_b = buf_flush_insert_in_flush_rbt(&block->page);
387
 
 
388
 
        } else {
389
 
 
390
 
                b = UT_LIST_GET_FIRST(buf_pool->flush_list);
391
 
 
392
 
                while (b && b->oldest_modification
393
 
                       > block->page.oldest_modification) {
394
 
                        ut_ad(b->in_flush_list);
395
 
                        prev_b = b;
396
 
                        b = UT_LIST_GET_NEXT(list, b);
397
 
                }
 
139
        b = UT_LIST_GET_FIRST(buf_pool->flush_list);
 
140
 
 
141
        while (b && b->oldest_modification > block->page.oldest_modification) {
 
142
                ut_ad(b->in_flush_list);
 
143
                prev_b = b;
 
144
                b = UT_LIST_GET_NEXT(list, b);
398
145
        }
399
146
 
400
147
        if (prev_b == NULL) {
405
152
        }
406
153
 
407
154
#if defined UNIV_DEBUG || defined UNIV_BUF_DEBUG
408
 
        ut_a(buf_flush_validate_low(buf_pool));
 
155
        ut_a(buf_flush_validate_low());
409
156
#endif /* UNIV_DEBUG || UNIV_BUF_DEBUG */
410
 
 
411
 
        buf_flush_list_mutex_exit(buf_pool);
412
157
}
413
158
 
414
159
/********************************************************************//**
422
167
        buf_page_t*     bpage)  /*!< in: buffer control block, must be
423
168
                                buf_page_in_file(bpage) and in the LRU list */
424
169
{
425
 
#ifdef UNIV_DEBUG
426
 
        buf_pool_t*     buf_pool = buf_pool_from_bpage(bpage);
427
 
        ut_ad(buf_pool_mutex_own(buf_pool));
428
 
#endif
 
170
        ut_ad(buf_pool_mutex_own());
429
171
        ut_ad(mutex_own(buf_page_get_mutex(bpage)));
430
172
        ut_ad(bpage->in_LRU_list);
431
173
 
458
200
                                buf_page_in_file(bpage) */
459
201
        enum buf_flush  flush_type)/*!< in: BUF_FLUSH_LRU or BUF_FLUSH_LIST */
460
202
{
461
 
#ifdef UNIV_DEBUG
462
 
        buf_pool_t*     buf_pool = buf_pool_from_bpage(bpage);
463
 
        ut_ad(buf_pool_mutex_own(buf_pool));
464
 
#endif
465
203
        ut_a(buf_page_in_file(bpage));
 
204
        ut_ad(buf_pool_mutex_own());
466
205
        ut_ad(mutex_own(buf_page_get_mutex(bpage)));
467
206
        ut_ad(flush_type == BUF_FLUSH_LRU || BUF_FLUSH_LIST);
468
207
 
495
234
/*=============*/
496
235
        buf_page_t*     bpage)  /*!< in: pointer to the block in question */
497
236
{
498
 
        buf_pool_t*     buf_pool = buf_pool_from_bpage(bpage);
499
 
 
500
 
        ut_ad(buf_pool_mutex_own(buf_pool));
 
237
        ut_ad(buf_pool_mutex_own());
501
238
        ut_ad(mutex_own(buf_page_get_mutex(bpage)));
502
239
        ut_ad(bpage->in_flush_list);
503
 
 
504
 
        buf_flush_list_mutex_enter(buf_pool);
 
240
        ut_d(bpage->in_flush_list = FALSE);
505
241
 
506
242
        switch (buf_page_get_state(bpage)) {
507
243
        case BUF_BLOCK_ZIP_PAGE:
508
 
                /* Clean compressed pages should not be on the flush list */
 
244
                /* clean compressed pages should not be on the flush list */
509
245
        case BUF_BLOCK_ZIP_FREE:
510
246
        case BUF_BLOCK_NOT_USED:
511
247
        case BUF_BLOCK_READY_FOR_USE:
523
259
                break;
524
260
        }
525
261
 
526
 
        /* If the flush_rbt is active then delete from there as well. */
527
 
        if (UNIV_LIKELY_NULL(buf_pool->flush_rbt)) {
528
 
                buf_flush_delete_from_flush_rbt(bpage);
529
 
        }
530
 
 
531
 
        /* Must be done after we have removed it from the flush_rbt
532
 
        because we assert on in_flush_list in comparison function. */
533
 
        ut_d(bpage->in_flush_list = FALSE);
534
 
 
535
262
        bpage->oldest_modification = 0;
536
263
 
537
 
#if defined UNIV_DEBUG || defined UNIV_BUF_DEBUG
538
 
        ut_a(buf_flush_validate_low(buf_pool));
539
 
#endif /* UNIV_DEBUG || UNIV_BUF_DEBUG */
540
 
 
541
 
        buf_flush_list_mutex_exit(buf_pool);
542
 
}
543
 
 
544
 
/*******************************************************************//**
545
 
Relocates a buffer control block on the flush_list.
546
 
Note that it is assumed that the contents of bpage have already been
547
 
copied to dpage.
548
 
IMPORTANT: When this function is called bpage and dpage are not
549
 
exact copies of each other. For example, they both will have different
550
 
::state. Also the ::list pointers in dpage may be stale. We need to
551
 
use the current list node (bpage) to do the list manipulation because
552
 
the list pointers could have changed between the time that we copied
553
 
the contents of bpage to the dpage and the flush list manipulation
554
 
below. */
555
 
UNIV_INTERN
556
 
void
557
 
buf_flush_relocate_on_flush_list(
558
 
/*=============================*/
559
 
        buf_page_t*     bpage,  /*!< in/out: control block being moved */
560
 
        buf_page_t*     dpage)  /*!< in/out: destination block */
561
 
{
562
 
        buf_page_t*     prev;
563
 
        buf_page_t*     prev_b = NULL;
564
 
        buf_pool_t*     buf_pool = buf_pool_from_bpage(bpage);
565
 
 
566
 
        ut_ad(buf_pool_mutex_own(buf_pool));
567
 
        /* Must reside in the same buffer pool. */
568
 
        ut_ad(buf_pool == buf_pool_from_bpage(dpage));
569
 
 
570
 
        ut_ad(mutex_own(buf_page_get_mutex(bpage)));
571
 
 
572
 
        buf_flush_list_mutex_enter(buf_pool);
573
 
 
574
 
        /* FIXME: At this point we have both buf_pool and flush_list
575
 
        mutexes. Theoretically removal of a block from flush list is
576
 
        only covered by flush_list mutex but currently we do
577
 
        have buf_pool mutex in buf_flush_remove() therefore this block
578
 
        is guaranteed to be in the flush list. We need to check if
579
 
        this will work without the assumption of block removing code
580
 
        having the buf_pool mutex. */
581
 
        ut_ad(bpage->in_flush_list);
582
 
        ut_ad(dpage->in_flush_list);
583
 
 
584
 
        /* If recovery is active we must swap the control blocks in
585
 
        the flush_rbt as well. */
586
 
        if (UNIV_LIKELY_NULL(buf_pool->flush_rbt)) {
587
 
                buf_flush_delete_from_flush_rbt(bpage);
588
 
                prev_b = buf_flush_insert_in_flush_rbt(dpage);
589
 
        }
590
 
 
591
 
        /* Must be done after we have removed it from the flush_rbt
592
 
        because we assert on in_flush_list in comparison function. */
593
 
        ut_d(bpage->in_flush_list = FALSE);
594
 
 
595
 
        prev = UT_LIST_GET_PREV(list, bpage);
596
 
        UT_LIST_REMOVE(list, buf_pool->flush_list, bpage);
597
 
 
598
 
        if (prev) {
599
 
                ut_ad(prev->in_flush_list);
600
 
                UT_LIST_INSERT_AFTER(
601
 
                        list,
602
 
                        buf_pool->flush_list,
603
 
                        prev, dpage);
604
 
        } else {
605
 
                UT_LIST_ADD_FIRST(
606
 
                        list,
607
 
                        buf_pool->flush_list,
608
 
                        dpage);
609
 
        }
610
 
 
611
 
        /* Just an extra check. Previous in flush_list
612
 
        should be the same control block as in flush_rbt. */
613
 
        ut_a(!buf_pool->flush_rbt || prev_b == prev);
614
 
 
615
 
#if defined UNIV_DEBUG || defined UNIV_BUF_DEBUG
616
 
        ut_a(buf_flush_validate_low(buf_pool));
617
 
#endif /* UNIV_DEBUG || UNIV_BUF_DEBUG */
618
 
 
619
 
        buf_flush_list_mutex_exit(buf_pool);
 
264
        ut_d(UT_LIST_VALIDATE(list, buf_page_t, buf_pool->flush_list,
 
265
                              ut_ad(ut_list_node_313->in_flush_list)));
620
266
}
621
267
 
622
268
/********************************************************************//**
628
274
        buf_page_t*     bpage)  /*!< in: pointer to the block in question */
629
275
{
630
276
        enum buf_flush  flush_type;
631
 
        buf_pool_t*     buf_pool = buf_pool_from_bpage(bpage);
632
277
 
633
278
        ut_ad(bpage);
634
279
 
649
294
        /* fprintf(stderr, "n pending flush %lu\n",
650
295
        buf_pool->n_flush[flush_type]); */
651
296
 
652
 
        if (buf_pool->n_flush[flush_type] == 0
653
 
            && buf_pool->init_flush[flush_type] == FALSE) {
 
297
        if ((buf_pool->n_flush[flush_type] == 0)
 
298
            && (buf_pool->init_flush[flush_type] == FALSE)) {
654
299
 
655
300
                /* The running flush batch has ended */
656
301
 
943
588
        zip_size = buf_page_get_zip_size(bpage);
944
589
 
945
590
        if (UNIV_UNLIKELY(zip_size)) {
946
 
                UNIV_MEM_ASSERT_RW(bpage->zip.data, zip_size);
947
591
                /* Copy the compressed page and clear the rest. */
948
592
                memcpy(trx_doublewrite->write_buf
949
593
                       + UNIV_PAGE_SIZE * trx_doublewrite->first_free,
953
597
                       + zip_size, 0, UNIV_PAGE_SIZE - zip_size);
954
598
        } else {
955
599
                ut_a(buf_page_get_state(bpage) == BUF_BLOCK_FILE_PAGE);
956
 
                UNIV_MEM_ASSERT_RW(((buf_block_t*) bpage)->frame,
957
 
                                   UNIV_PAGE_SIZE);
958
600
 
959
601
                memcpy(trx_doublewrite->write_buf
960
602
                       + UNIV_PAGE_SIZE * trx_doublewrite->first_free,
1010
652
                case FIL_PAGE_TYPE_ZBLOB:
1011
653
                case FIL_PAGE_TYPE_ZBLOB2:
1012
654
                case FIL_PAGE_INDEX:
1013
 
                        mach_write_to_8(page_zip->data
1014
 
                                        + FIL_PAGE_LSN, newest_lsn);
 
655
                        mach_write_ull(page_zip->data
 
656
                                       + FIL_PAGE_LSN, newest_lsn);
1015
657
                        memset(page_zip->data + FIL_PAGE_FILE_FLUSH_LSN, 0, 8);
1016
658
                        mach_write_to_4(page_zip->data
1017
659
                                        + FIL_PAGE_SPACE_OR_CHKSUM,
1033
675
        }
1034
676
 
1035
677
        /* Write the newest modification lsn to the page header and trailer */
1036
 
        mach_write_to_8(page + FIL_PAGE_LSN, newest_lsn);
 
678
        mach_write_ull(page + FIL_PAGE_LSN, newest_lsn);
1037
679
 
1038
 
        mach_write_to_8(page + UNIV_PAGE_SIZE - FIL_PAGE_END_LSN_OLD_CHKSUM,
1039
 
                        newest_lsn);
 
680
        mach_write_ull(page + UNIV_PAGE_SIZE - FIL_PAGE_END_LSN_OLD_CHKSUM,
 
681
                       newest_lsn);
1040
682
 
1041
683
        /* Store the new formula checksum */
1042
684
 
1069
711
{
1070
712
        ulint   zip_size        = buf_page_get_zip_size(bpage);
1071
713
        page_t* frame           = NULL;
1072
 
 
1073
 
#ifdef UNIV_DEBUG
1074
 
        buf_pool_t*     buf_pool = buf_pool_from_bpage(bpage);
1075
 
        ut_ad(!buf_pool_mutex_own(buf_pool));
1076
 
#endif
1077
 
 
1078
714
#ifdef UNIV_LOG_DEBUG
1079
715
        static ibool univ_log_debug_warned;
1080
716
#endif /* UNIV_LOG_DEBUG */
1086
722
        io_fixed and oldest_modification != 0.  Thus, it cannot be
1087
723
        relocated in the buffer pool or removed from flush_list or
1088
724
        LRU_list. */
1089
 
        ut_ad(!buf_pool_mutex_own(buf_pool));
1090
 
        ut_ad(!buf_flush_list_mutex_own(buf_pool));
 
725
        ut_ad(!buf_pool_mutex_own());
1091
726
        ut_ad(!mutex_own(buf_page_get_mutex(bpage)));
1092
727
        ut_ad(buf_page_get_io_fix(bpage) == BUF_IO_WRITE);
1093
728
        ut_ad(bpage->oldest_modification != 0);
1124
759
                        ut_a(mach_read_from_4(frame + FIL_PAGE_SPACE_OR_CHKSUM)
1125
760
                             == page_zip_calc_checksum(frame, zip_size));
1126
761
                }
1127
 
                mach_write_to_8(frame + FIL_PAGE_LSN,
1128
 
                                bpage->newest_modification);
 
762
                mach_write_ull(frame + FIL_PAGE_LSN,
 
763
                               bpage->newest_modification);
1129
764
                memset(frame + FIL_PAGE_FILE_FLUSH_LSN, 0, 8);
1130
765
                break;
1131
766
        case BUF_BLOCK_FILE_PAGE:
1156
791
Writes a flushable page asynchronously from the buffer pool to a file.
1157
792
NOTE: in simulated aio we must call
1158
793
os_aio_simulated_wake_handler_threads after we have posted a batch of
1159
 
writes! NOTE: buf_pool->mutex and buf_page_get_mutex(bpage) must be
 
794
writes! NOTE: buf_pool_mutex and buf_page_get_mutex(bpage) must be
1160
795
held upon entering this function, and they will be released by this
1161
796
function. */
1162
797
static
1163
798
void
1164
799
buf_flush_page(
1165
800
/*===========*/
1166
 
        buf_pool_t*     buf_pool,       /*!< in: buffer pool instance */
1167
801
        buf_page_t*     bpage,          /*!< in: buffer control block */
1168
802
        enum buf_flush  flush_type)     /*!< in: BUF_FLUSH_LRU
1169
803
                                        or BUF_FLUSH_LIST */
1172
806
        ibool           is_uncompressed;
1173
807
 
1174
808
        ut_ad(flush_type == BUF_FLUSH_LRU || flush_type == BUF_FLUSH_LIST);
1175
 
        ut_ad(buf_pool_mutex_own(buf_pool));
 
809
        ut_ad(buf_pool_mutex_own());
1176
810
        ut_ad(buf_page_in_file(bpage));
1177
811
 
1178
812
        block_mutex = buf_page_get_mutex(bpage);
1192
826
        buf_pool->n_flush[flush_type]++;
1193
827
 
1194
828
        is_uncompressed = (buf_page_get_state(bpage) == BUF_BLOCK_FILE_PAGE);
1195
 
        ut_ad(is_uncompressed == (block_mutex != &buf_pool->zip_mutex));
 
829
        ut_ad(is_uncompressed == (block_mutex != &buf_pool_zip_mutex));
1196
830
 
1197
831
        switch (flush_type) {
1198
832
                ibool   is_s_latched;
1208
842
                }
1209
843
 
1210
844
                mutex_exit(block_mutex);
1211
 
                buf_pool_mutex_exit(buf_pool);
 
845
                buf_pool_mutex_exit();
1212
846
 
1213
847
                /* Even though bpage is not protected by any mutex at
1214
848
                this point, it is safe to access bpage, because it is
1245
879
                immediately. */
1246
880
 
1247
881
                mutex_exit(block_mutex);
1248
 
                buf_pool_mutex_exit(buf_pool);
 
882
                buf_pool_mutex_exit();
1249
883
                break;
1250
884
 
1251
885
        default:
1276
910
/*====================*/
1277
911
        ulint           space,          /*!< in: space id */
1278
912
        ulint           offset,         /*!< in: page offset */
1279
 
        enum buf_flush  flush_type,     /*!< in: BUF_FLUSH_LRU or
 
913
        enum buf_flush  flush_type)     /*!< in: BUF_FLUSH_LRU or
1280
914
                                        BUF_FLUSH_LIST */
1281
 
        ulint           n_flushed,      /*!< in: number of pages
1282
 
                                        flushed so far in this batch */
1283
 
        ulint           n_to_flush)     /*!< in: maximum number of pages
1284
 
                                        we are allowed to flush */
1285
915
{
 
916
        buf_page_t*     bpage;
 
917
        ulint           low, high;
 
918
        ulint           count           = 0;
1286
919
        ulint           i;
1287
 
        ulint           low;
1288
 
        ulint           high;
1289
 
        ulint           count = 0;
1290
 
        buf_pool_t*     buf_pool = buf_pool_get(space, offset);
1291
920
 
1292
921
        ut_ad(flush_type == BUF_FLUSH_LRU || flush_type == BUF_FLUSH_LIST);
1293
922
 
1294
923
        if (UT_LIST_GET_LEN(buf_pool->LRU) < BUF_LRU_OLD_MIN_LEN) {
1295
 
                /* If there is little space, it is better not to flush
1296
 
                any block except from the end of the LRU list */
 
924
                /* If there is little space, it is better not to flush any
 
925
                block except from the end of the LRU list */
1297
926
 
1298
927
                low = offset;
1299
928
                high = offset + 1;
1300
929
        } else {
1301
 
                /* When flushed, dirty blocks are searched in
1302
 
                neighborhoods of this size, and flushed along with the
1303
 
                original page. */
 
930
                /* When flushed, dirty blocks are searched in neighborhoods of
 
931
                this size, and flushed along with the original page. */
1304
932
 
1305
 
                ulint   buf_flush_area;
1306
 
        
1307
 
                buf_flush_area  = ut_min(
1308
 
                        BUF_READ_AHEAD_AREA(buf_pool),
1309
 
                        buf_pool->curr_size / 16);
 
933
                ulint   buf_flush_area  = ut_min(BUF_READ_AHEAD_AREA,
 
934
                                                 buf_pool->curr_size / 16);
1310
935
 
1311
936
                low = (offset / buf_flush_area) * buf_flush_area;
1312
937
                high = (offset / buf_flush_area + 1) * buf_flush_area;
1318
943
                high = fil_space_get_size(space);
1319
944
        }
1320
945
 
 
946
        buf_pool_mutex_enter();
 
947
 
1321
948
        for (i = low; i < high; i++) {
1322
949
 
1323
 
                buf_page_t*     bpage;
1324
 
 
1325
 
                if ((count + n_flushed) >= n_to_flush) {
1326
 
 
1327
 
                        /* We have already flushed enough pages and
1328
 
                        should call it a day. There is, however, one
1329
 
                        exception. If the page whose neighbors we
1330
 
                        are flushing has not been flushed yet then
1331
 
                        we'll try to flush the victim that we
1332
 
                        selected originally. */
1333
 
                        if (i <= offset) {
1334
 
                                i = offset;
1335
 
                        } else {
1336
 
                                break;
1337
 
                        }
1338
 
                }
1339
 
 
1340
 
                buf_pool = buf_pool_get(space, i);
1341
 
 
1342
 
                buf_pool_mutex_enter(buf_pool);
1343
 
 
1344
 
                /* We only want to flush pages from this buffer pool. */
1345
 
                bpage = buf_page_hash_get(buf_pool, space, i);
 
950
                bpage = buf_page_hash_get(space, i);
1346
951
 
1347
952
                if (!bpage) {
1348
953
 
1349
 
                        buf_pool_mutex_exit(buf_pool);
1350
954
                        continue;
1351
955
                }
1352
956
 
1365
969
                        if (buf_flush_ready_for_flush(bpage, flush_type)
1366
970
                            && (i == offset || !bpage->buf_fix_count)) {
1367
971
                                /* We only try to flush those
1368
 
                                neighbors != offset where the buf fix
1369
 
                                count is zero, as we then know that we
1370
 
                                probably can latch the page without a
1371
 
                                semaphore wait. Semaphore waits are
1372
 
                                expensive because we must flush the
1373
 
                                doublewrite buffer before we start
 
972
                                neighbors != offset where the buf fix count is
 
973
                                zero, as we then know that we probably can
 
974
                                latch the page without a semaphore wait.
 
975
                                Semaphore waits are expensive because we must
 
976
                                flush the doublewrite buffer before we start
1374
977
                                waiting. */
1375
978
 
1376
 
                                buf_flush_page(buf_pool, bpage, flush_type);
 
979
                                buf_flush_page(bpage, flush_type);
1377
980
                                ut_ad(!mutex_own(block_mutex));
1378
 
                                ut_ad(!buf_pool_mutex_own(buf_pool));
1379
981
                                count++;
1380
 
                                continue;
 
982
 
 
983
                                buf_pool_mutex_enter();
1381
984
                        } else {
1382
985
                                mutex_exit(block_mutex);
1383
986
                        }
1384
987
                }
1385
 
                buf_pool_mutex_exit(buf_pool);
1386
 
        }
1387
 
 
1388
 
        return(count);
1389
 
}
1390
 
 
1391
 
/********************************************************************//**
1392
 
Check if the block is modified and ready for flushing. If the the block
1393
 
is ready to flush then flush the page and try o flush its neighbors.
1394
 
 
1395
 
@return TRUE if buf_pool mutex was not released during this function.
1396
 
This does not guarantee that some pages were written as well.
1397
 
Number of pages written are incremented to the count. */
1398
 
static
1399
 
ibool
1400
 
buf_flush_page_and_try_neighbors(
1401
 
/*=============================*/
1402
 
        buf_page_t*     bpage,          /*!< in: buffer control block,
1403
 
                                        must be
1404
 
                                        buf_page_in_file(bpage) */
1405
 
        enum buf_flush  flush_type,     /*!< in: BUF_FLUSH_LRU
1406
 
                                        or BUF_FLUSH_LIST */
1407
 
        ulint           n_to_flush,     /*!< in: number of pages to
1408
 
                                        flush */
1409
 
        ulint*          count)          /*!< in/out: number of pages
1410
 
                                        flushed */
1411
 
{
1412
 
        mutex_t*        block_mutex;
1413
 
        ibool           flushed = FALSE;
1414
 
#ifdef UNIV_DEBUG
1415
 
        buf_pool_t*     buf_pool = buf_pool_from_bpage(bpage);
1416
 
#endif /* UNIV_DEBUG */
1417
 
 
1418
 
        ut_ad(buf_pool_mutex_own(buf_pool));
1419
 
 
1420
 
        block_mutex = buf_page_get_mutex(bpage);
1421
 
        mutex_enter(block_mutex);
1422
 
 
1423
 
        ut_a(buf_page_in_file(bpage));
1424
 
 
1425
 
        if (buf_flush_ready_for_flush(bpage, flush_type)) {
1426
 
                ulint           space;
1427
 
                ulint           offset;
1428
 
                buf_pool_t*     buf_pool;
1429
 
 
1430
 
                buf_pool = buf_pool_from_bpage(bpage);
1431
 
 
1432
 
                buf_pool_mutex_exit(buf_pool);
1433
 
 
1434
 
                /* These fields are protected by both the
1435
 
                buffer pool mutex and block mutex. */
1436
 
                space = buf_page_get_space(bpage);
1437
 
                offset = buf_page_get_page_no(bpage);
1438
 
 
1439
 
                mutex_exit(block_mutex);
1440
 
 
1441
 
                /* Try to flush also all the neighbors */
1442
 
                *count += buf_flush_try_neighbors(space,
1443
 
                                                  offset,
1444
 
                                                  flush_type,
1445
 
                                                  *count,
1446
 
                                                  n_to_flush);
1447
 
 
1448
 
                buf_pool_mutex_enter(buf_pool);
1449
 
                flushed = TRUE;
1450
 
        } else {
1451
 
                mutex_exit(block_mutex);
1452
 
        }
1453
 
 
1454
 
        ut_ad(buf_pool_mutex_own(buf_pool));
1455
 
 
1456
 
        return(flushed);
1457
 
}
1458
 
 
1459
 
/*******************************************************************//**
1460
 
This utility flushes dirty blocks from the end of the LRU list.
1461
 
In the case of an LRU flush the calling thread may own latches to
1462
 
pages: to avoid deadlocks, this function must be written so that it
1463
 
cannot end up waiting for these latches!
1464
 
@return number of blocks for which the write request was queued. */
1465
 
static
1466
 
ulint
1467
 
buf_flush_LRU_list_batch(
1468
 
/*=====================*/
1469
 
        buf_pool_t*     buf_pool,       /*!< in: buffer pool instance */
1470
 
        ulint           max)            /*!< in: max of blocks to flush */
1471
 
{
1472
 
        buf_page_t*     bpage;
1473
 
        ulint           count = 0;
1474
 
 
1475
 
        ut_ad(buf_pool_mutex_own(buf_pool));
1476
 
 
1477
 
        do {
1478
 
                /* Start from the end of the list looking for a
1479
 
                suitable block to be flushed. */
1480
 
                bpage = UT_LIST_GET_LAST(buf_pool->LRU);
1481
 
 
1482
 
                /* Iterate backwards over the flush list till we find
1483
 
                a page that isn't ready for flushing. */
1484
 
                while (bpage != NULL
1485
 
                       && !buf_flush_page_and_try_neighbors(
1486
 
                                bpage, BUF_FLUSH_LRU, max, &count)) {
1487
 
 
1488
 
                        bpage = UT_LIST_GET_PREV(LRU, bpage);
1489
 
                }
1490
 
        } while (bpage != NULL && count < max);
1491
 
 
1492
 
        /* We keep track of all flushes happening as part of LRU
1493
 
        flush. When estimating the desired rate at which flush_list
1494
 
        should be flushed, we factor in this value. */
1495
 
        buf_lru_flush_page_count += count;
1496
 
 
1497
 
        ut_ad(buf_pool_mutex_own(buf_pool));
1498
 
 
1499
 
        return(count);
1500
 
}
1501
 
 
1502
 
/*******************************************************************//**
1503
 
This utility flushes dirty blocks from the end of the flush_list.
1504
 
the calling thread is not allowed to own any latches on pages!
1505
 
@return number of blocks for which the write request was queued;
1506
 
ULINT_UNDEFINED if there was a flush of the same type already
1507
 
running */
1508
 
static
1509
 
ulint
1510
 
buf_flush_flush_list_batch(
1511
 
/*=======================*/
1512
 
        buf_pool_t*     buf_pool,       /*!< in: buffer pool instance */
1513
 
        ulint           min_n,          /*!< in: wished minimum mumber
1514
 
                                        of blocks flushed (it is not
1515
 
                                        guaranteed that the actual
1516
 
                                        number is that big, though) */
1517
 
        ib_uint64_t     lsn_limit)      /*!< all blocks whose
1518
 
                                        oldest_modification is smaller
1519
 
                                        than this should be flushed (if
1520
 
                                        their number does not exceed
1521
 
                                        min_n) */
1522
 
{
1523
 
        ulint           len;
1524
 
        buf_page_t*     bpage;
1525
 
        ulint           count = 0;
1526
 
 
1527
 
        ut_ad(buf_pool_mutex_own(buf_pool));
1528
 
 
1529
 
        /* If we have flushed enough, leave the loop */
1530
 
        do {
1531
 
                /* Start from the end of the list looking for a suitable
1532
 
                block to be flushed. */
1533
 
 
1534
 
                buf_flush_list_mutex_enter(buf_pool);
1535
 
 
1536
 
                /* We use len here because theoretically insertions can
1537
 
                happen in the flush_list below while we are traversing
1538
 
                it for a suitable candidate for flushing. We'd like to
1539
 
                set a limit on how farther we are willing to traverse
1540
 
                the list. */
1541
 
                len = UT_LIST_GET_LEN(buf_pool->flush_list);
1542
 
                bpage = UT_LIST_GET_LAST(buf_pool->flush_list);
1543
 
 
1544
 
                if (bpage) {
1545
 
                        ut_a(bpage->oldest_modification > 0);
1546
 
                }
1547
 
 
1548
 
                if (!bpage || bpage->oldest_modification >= lsn_limit) {
1549
 
 
1550
 
                        /* We have flushed enough */
1551
 
                        buf_flush_list_mutex_exit(buf_pool);
1552
 
                        break;
1553
 
                }
1554
 
 
1555
 
                ut_a(bpage->oldest_modification > 0);
1556
 
 
1557
 
                ut_ad(bpage->in_flush_list);
1558
 
 
1559
 
                buf_flush_list_mutex_exit(buf_pool);
1560
 
 
1561
 
                /* The list may change during the flushing and we cannot
1562
 
                safely preserve within this function a pointer to a
1563
 
                block in the list! */
1564
 
                while (bpage != NULL
1565
 
                       && len > 0
1566
 
                       && !buf_flush_page_and_try_neighbors(
1567
 
                                bpage, BUF_FLUSH_LIST, min_n, &count)) {
1568
 
 
1569
 
                        buf_flush_list_mutex_enter(buf_pool);
1570
 
 
1571
 
                        /* If we are here that means that buf_pool->mutex
1572
 
                         was not released in buf_flush_page_and_try_neighbors()
1573
 
                        above and this guarantees that bpage didn't get
1574
 
                        relocated since we released the flush_list
1575
 
                        mutex above. There is a chance, however, that
1576
 
                        the bpage got removed from flush_list (not
1577
 
                        currently possible because flush_list_remove()
1578
 
                        also obtains buf_pool mutex but that may change
1579
 
                        in future). To avoid this scenario we check
1580
 
                        the oldest_modification and if it is zero
1581
 
                        we start all over again. */
1582
 
                        if (bpage->oldest_modification == 0) {
1583
 
                                buf_flush_list_mutex_exit(buf_pool);
1584
 
                                break;
1585
 
                        }
1586
 
 
1587
 
                        bpage = UT_LIST_GET_PREV(list, bpage);
1588
 
 
1589
 
                        ut_ad(!bpage || bpage->in_flush_list);
1590
 
 
1591
 
                        buf_flush_list_mutex_exit(buf_pool);
1592
 
 
1593
 
                        --len;
1594
 
                }
1595
 
 
1596
 
        } while (count < min_n && bpage != NULL && len > 0);
1597
 
 
1598
 
        ut_ad(buf_pool_mutex_own(buf_pool));
 
988
        }
 
989
 
 
990
        buf_pool_mutex_exit();
1599
991
 
1600
992
        return(count);
1601
993
}
1608
1000
the calling thread is not allowed to own any latches on pages!
1609
1001
@return number of blocks for which the write request was queued;
1610
1002
ULINT_UNDEFINED if there was a flush of the same type already running */
1611
 
static
 
1003
UNIV_INTERN
1612
1004
ulint
1613
1005
buf_flush_batch(
1614
1006
/*============*/
1615
 
        buf_pool_t*     buf_pool,       /*!< in: buffer pool instance */
1616
1007
        enum buf_flush  flush_type,     /*!< in: BUF_FLUSH_LRU or
1617
1008
                                        BUF_FLUSH_LIST; if BUF_FLUSH_LIST,
1618
1009
                                        then the caller must not own any
1620
1011
        ulint           min_n,          /*!< in: wished minimum mumber of blocks
1621
1012
                                        flushed (it is not guaranteed that the
1622
1013
                                        actual number is that big, though) */
1623
 
        ib_uint64_t     lsn_limit)      /*!< in: in the case of BUF_FLUSH_LIST
1624
 
                                        all blocks whose oldest_modification is
 
1014
        ib_uint64_t     lsn_limit)      /*!< in the case BUF_FLUSH_LIST all
 
1015
                                        blocks whose oldest_modification is
1625
1016
                                        smaller than this should be flushed
1626
1017
                                        (if their number does not exceed
1627
1018
                                        min_n), otherwise ignored */
1628
1019
{
1629
 
        ulint           count   = 0;
 
1020
        buf_page_t*     bpage;
 
1021
        ulint           page_count      = 0;
 
1022
        ulint           old_page_count;
 
1023
        ulint           space;
 
1024
        ulint           offset;
1630
1025
 
1631
 
        ut_ad(flush_type == BUF_FLUSH_LRU || flush_type == BUF_FLUSH_LIST);
 
1026
        ut_ad((flush_type == BUF_FLUSH_LRU)
 
1027
              || (flush_type == BUF_FLUSH_LIST));
1632
1028
#ifdef UNIV_SYNC_DEBUG
1633
1029
        ut_ad((flush_type != BUF_FLUSH_LIST)
1634
1030
              || sync_thread_levels_empty_gen(TRUE));
1635
1031
#endif /* UNIV_SYNC_DEBUG */
1636
 
 
1637
 
        buf_pool_mutex_enter(buf_pool);
1638
 
 
1639
 
        /* Note: The buffer pool mutex is released and reacquired within
1640
 
        the flush functions. */
1641
 
        switch(flush_type) {
1642
 
        case BUF_FLUSH_LRU:
1643
 
                count = buf_flush_LRU_list_batch(buf_pool, min_n);
1644
 
                break;
1645
 
        case BUF_FLUSH_LIST:
1646
 
                count = buf_flush_flush_list_batch(buf_pool, min_n, lsn_limit);
1647
 
                break;
1648
 
        default:
1649
 
                ut_error;
1650
 
        }
1651
 
 
1652
 
        buf_pool_mutex_exit(buf_pool);
1653
 
 
1654
 
        buf_flush_buffered_writes();
1655
 
 
1656
 
#ifdef UNIV_DEBUG
1657
 
        if (buf_debug_prints && count > 0) {
1658
 
                fprintf(stderr, flush_type == BUF_FLUSH_LRU
1659
 
                        ? "Flushed %lu pages in LRU flush\n"
1660
 
                        : "Flushed %lu pages in flush list flush\n",
1661
 
                        (ulong) count);
1662
 
        }
1663
 
#endif /* UNIV_DEBUG */
1664
 
 
1665
 
        srv_buf_pool_flushed += count;
1666
 
 
1667
 
        return(count);
1668
 
}
1669
 
 
1670
 
/******************************************************************//**
1671
 
Gather the aggregated stats for both flush list and LRU list flushing */
1672
 
static
1673
 
void
1674
 
buf_flush_common(
1675
 
/*=============*/
1676
 
        enum buf_flush  flush_type,     /*!< in: type of flush */
1677
 
        ulint           page_count)     /*!< in: number of pages flushed */
1678
 
{
1679
 
        buf_flush_buffered_writes();
1680
 
 
1681
 
        ut_a(flush_type == BUF_FLUSH_LRU || flush_type == BUF_FLUSH_LIST);
 
1032
        buf_pool_mutex_enter();
 
1033
 
 
1034
        if ((buf_pool->n_flush[flush_type] > 0)
 
1035
            || (buf_pool->init_flush[flush_type] == TRUE)) {
 
1036
 
 
1037
                /* There is already a flush batch of the same type running */
 
1038
 
 
1039
                buf_pool_mutex_exit();
 
1040
 
 
1041
                return(ULINT_UNDEFINED);
 
1042
        }
 
1043
 
 
1044
        buf_pool->init_flush[flush_type] = TRUE;
 
1045
 
 
1046
        bool done_with_loop= false;
 
1047
        for (;done_with_loop != true;) {
 
1048
flush_next:
 
1049
                /* If we have flushed enough, leave the loop */
 
1050
                if (page_count >= min_n) {
 
1051
 
 
1052
                        break;
 
1053
                }
 
1054
 
 
1055
                /* Start from the end of the list looking for a suitable
 
1056
                block to be flushed. */
 
1057
 
 
1058
                if (flush_type == BUF_FLUSH_LRU) {
 
1059
                        bpage = UT_LIST_GET_LAST(buf_pool->LRU);
 
1060
                } else {
 
1061
                        ut_ad(flush_type == BUF_FLUSH_LIST);
 
1062
 
 
1063
                        bpage = UT_LIST_GET_LAST(buf_pool->flush_list);
 
1064
                        if (!bpage
 
1065
                            || bpage->oldest_modification >= lsn_limit) {
 
1066
                                /* We have flushed enough */
 
1067
 
 
1068
                                break;
 
1069
                        }
 
1070
                        ut_ad(bpage->in_flush_list);
 
1071
                }
 
1072
 
 
1073
                /* Note that after finding a single flushable page, we try to
 
1074
                flush also all its neighbors, and after that start from the
 
1075
                END of the LRU list or flush list again: the list may change
 
1076
                during the flushing and we cannot safely preserve within this
 
1077
                function a pointer to a block in the list! */
 
1078
 
 
1079
                do {
 
1080
                        mutex_t*block_mutex = buf_page_get_mutex(bpage);
 
1081
                        ibool   ready;
 
1082
 
 
1083
                        ut_a(buf_page_in_file(bpage));
 
1084
 
 
1085
                        mutex_enter(block_mutex);
 
1086
                        ready = buf_flush_ready_for_flush(bpage, flush_type);
 
1087
                        mutex_exit(block_mutex);
 
1088
 
 
1089
                        if (ready) {
 
1090
                                space = buf_page_get_space(bpage);
 
1091
                                offset = buf_page_get_page_no(bpage);
 
1092
 
 
1093
                                buf_pool_mutex_exit();
 
1094
 
 
1095
                                old_page_count = page_count;
 
1096
 
 
1097
                                /* Try to flush also all the neighbors */
 
1098
                                page_count += buf_flush_try_neighbors(
 
1099
                                        space, offset, flush_type);
 
1100
                                /* fprintf(stderr,
 
1101
                                "Flush type %lu, page no %lu, neighb %lu\n",
 
1102
                                flush_type, offset,
 
1103
                                page_count - old_page_count); */
 
1104
 
 
1105
                                buf_pool_mutex_enter();
 
1106
                                goto flush_next;
 
1107
 
 
1108
                        } else if (flush_type == BUF_FLUSH_LRU) {
 
1109
                                bpage = UT_LIST_GET_PREV(LRU, bpage);
 
1110
                        } else {
 
1111
                                ut_ad(flush_type == BUF_FLUSH_LIST);
 
1112
 
 
1113
                                bpage = UT_LIST_GET_PREV(list, bpage);
 
1114
                                ut_ad(!bpage || bpage->in_flush_list);
 
1115
                        }
 
1116
                } while (bpage != NULL);
 
1117
 
 
1118
                /* If we could not find anything to flush, leave the loop */
 
1119
 
 
1120
                done_with_loop= true;
 
1121
 
 
1122
        }
 
1123
 
 
1124
        buf_pool->init_flush[flush_type] = FALSE;
 
1125
 
 
1126
        if (buf_pool->n_flush[flush_type] == 0) {
 
1127
 
 
1128
                /* The running flush batch has ended */
 
1129
 
 
1130
                os_event_set(buf_pool->no_flush[flush_type]);
 
1131
        }
 
1132
 
 
1133
        buf_pool_mutex_exit();
 
1134
 
 
1135
        buf_flush_buffered_writes();
1682
1136
 
1683
1137
#ifdef UNIV_DEBUG
1684
1138
        if (buf_debug_prints && page_count > 0) {
 
1139
                ut_a(flush_type == BUF_FLUSH_LRU
 
1140
                     || flush_type == BUF_FLUSH_LIST);
1685
1141
                fprintf(stderr, flush_type == BUF_FLUSH_LRU
1686
1142
                        ? "Flushed %lu pages in LRU flush\n"
1687
1143
                        : "Flushed %lu pages in flush list flush\n",
1691
1147
 
1692
1148
        srv_buf_pool_flushed += page_count;
1693
1149
 
 
1150
        /* We keep track of all flushes happening as part of LRU
 
1151
        flush. When estimating the desired rate at which flush_list
 
1152
        should be flushed we factor in this value. */
1694
1153
        if (flush_type == BUF_FLUSH_LRU) {
1695
 
                /* We keep track of all flushes happening as part of LRU
1696
 
                flush. When estimating the desired rate at which flush_list
1697
 
                should be flushed we factor in this value. */
1698
1154
                buf_lru_flush_page_count += page_count;
1699
1155
        }
1700
 
}
1701
 
 
1702
 
/******************************************************************//**
1703
 
Start a buffer flush batch for LRU or flush list */
1704
 
static
1705
 
ibool
1706
 
buf_flush_start(
1707
 
/*============*/
1708
 
        buf_pool_t*     buf_pool,       /*!< buffer pool instance */
1709
 
        enum buf_flush  flush_type)     /*!< in: BUF_FLUSH_LRU
1710
 
                                        or BUF_FLUSH_LIST */
1711
 
{
1712
 
        buf_pool_mutex_enter(buf_pool);
1713
 
 
1714
 
        if (buf_pool->n_flush[flush_type] > 0
1715
 
           || buf_pool->init_flush[flush_type] == TRUE) {
1716
 
 
1717
 
                /* There is already a flush batch of the same type running */
1718
 
 
1719
 
                buf_pool_mutex_exit(buf_pool);
1720
 
 
1721
 
                return(FALSE);
1722
 
        }
1723
 
 
1724
 
        buf_pool->init_flush[flush_type] = TRUE;
1725
 
 
1726
 
        buf_pool_mutex_exit(buf_pool);
1727
 
 
1728
 
        return(TRUE);
1729
 
}
1730
 
 
1731
 
/******************************************************************//**
1732
 
End a buffer flush batch for LRU or flush list */
1733
 
static
1734
 
void
1735
 
buf_flush_end(
1736
 
/*==========*/
1737
 
        buf_pool_t*     buf_pool,       /*!< buffer pool instance */
1738
 
        enum buf_flush  flush_type)     /*!< in: BUF_FLUSH_LRU
1739
 
                                        or BUF_FLUSH_LIST */
1740
 
{
1741
 
        buf_pool_mutex_enter(buf_pool);
1742
 
 
1743
 
        buf_pool->init_flush[flush_type] = FALSE;
1744
 
 
1745
 
        if (buf_pool->n_flush[flush_type] == 0) {
1746
 
 
1747
 
                /* The running flush batch has ended */
1748
 
 
1749
 
                os_event_set(buf_pool->no_flush[flush_type]);
1750
 
        }
1751
 
 
1752
 
        buf_pool_mutex_exit(buf_pool);
 
1156
 
 
1157
        return(page_count);
1753
1158
}
1754
1159
 
1755
1160
/******************************************************************//**
1758
1163
void
1759
1164
buf_flush_wait_batch_end(
1760
1165
/*=====================*/
1761
 
        buf_pool_t*     buf_pool,       /*!< buffer pool instance */
1762
 
        enum buf_flush  type)           /*!< in: BUF_FLUSH_LRU
1763
 
                                        or BUF_FLUSH_LIST */
1764
 
{
1765
 
        ut_ad(type == BUF_FLUSH_LRU || type == BUF_FLUSH_LIST);
1766
 
 
1767
 
        if (buf_pool == NULL) {
1768
 
                ulint   i;
1769
 
 
1770
 
                for (i = 0; i < srv_buf_pool_instances; ++i) {
1771
 
                        buf_pool_t*     buf_pool;
1772
 
 
1773
 
                        buf_pool = buf_pool_from_array(i);
1774
 
 
1775
 
                        os_event_wait(buf_pool->no_flush[type]);
1776
 
                }
1777
 
        } else {
1778
 
                os_event_wait(buf_pool->no_flush[type]);
1779
 
        }
1780
 
}
1781
 
 
1782
 
/*******************************************************************//**
1783
 
This utility flushes dirty blocks from the end of the LRU list.
1784
 
NOTE: The calling thread may own latches to pages: to avoid deadlocks,
1785
 
this function must be written so that it cannot end up waiting for these
1786
 
latches!
1787
 
@return number of blocks for which the write request was queued;
1788
 
ULINT_UNDEFINED if there was a flush of the same type already running */
1789
 
UNIV_INTERN
1790
 
ulint
1791
 
buf_flush_LRU(
1792
 
/*==========*/
1793
 
        buf_pool_t*     buf_pool,       /*!< in: buffer pool instance */
1794
 
        ulint           min_n)          /*!< in: wished minimum mumber of blocks
1795
 
                                        flushed (it is not guaranteed that the
1796
 
                                        actual number is that big, though) */
1797
 
{
1798
 
        ulint           page_count;
1799
 
 
1800
 
        if (!buf_flush_start(buf_pool, BUF_FLUSH_LRU)) {
1801
 
                return(ULINT_UNDEFINED);
1802
 
        }
1803
 
 
1804
 
        page_count = buf_flush_batch(buf_pool, BUF_FLUSH_LRU, min_n, 0);
1805
 
 
1806
 
        buf_flush_end(buf_pool, BUF_FLUSH_LRU);
1807
 
 
1808
 
        buf_flush_common(BUF_FLUSH_LRU, page_count);
1809
 
 
1810
 
        return(page_count);
1811
 
}
1812
 
 
1813
 
/*******************************************************************//**
1814
 
This utility flushes dirty blocks from the end of the flush list of
1815
 
all buffer pool instances.
1816
 
NOTE: The calling thread is not allowed to own any latches on pages!
1817
 
@return number of blocks for which the write request was queued;
1818
 
ULINT_UNDEFINED if there was a flush of the same type already running */
1819
 
UNIV_INTERN
1820
 
ulint
1821
 
buf_flush_list(
1822
 
/*===========*/
1823
 
        ulint           min_n,          /*!< in: wished minimum mumber of blocks
1824
 
                                        flushed (it is not guaranteed that the
1825
 
                                        actual number is that big, though) */
1826
 
        ib_uint64_t     lsn_limit)      /*!< in the case BUF_FLUSH_LIST all
1827
 
                                        blocks whose oldest_modification is
1828
 
                                        smaller than this should be flushed
1829
 
                                        (if their number does not exceed
1830
 
                                        min_n), otherwise ignored */
1831
 
{
1832
 
        ulint           i;
1833
 
        ulint           total_page_count = 0;
1834
 
        ibool           skipped = FALSE;
1835
 
 
1836
 
        if (min_n != ULINT_MAX) {
1837
 
                /* Ensure that flushing is spread evenly amongst the
1838
 
                buffer pool instances. When min_n is ULINT_MAX
1839
 
                we need to flush everything up to the lsn limit
1840
 
                so no limit here. */
1841
 
                min_n = (min_n + srv_buf_pool_instances - 1)
1842
 
                         / srv_buf_pool_instances;
1843
 
        }
1844
 
 
1845
 
        /* Flush to lsn_limit in all buffer pool instances */
1846
 
        for (i = 0; i < srv_buf_pool_instances; i++) {
1847
 
                buf_pool_t*     buf_pool;
1848
 
                ulint           page_count = 0;
1849
 
 
1850
 
                buf_pool = buf_pool_from_array(i);
1851
 
 
1852
 
                if (!buf_flush_start(buf_pool, BUF_FLUSH_LIST)) {
1853
 
                        /* We have two choices here. If lsn_limit was
1854
 
                        specified then skipping an instance of buffer
1855
 
                        pool means we cannot guarantee that all pages
1856
 
                        up to lsn_limit has been flushed. We can
1857
 
                        return right now with failure or we can try
1858
 
                        to flush remaining buffer pools up to the
1859
 
                        lsn_limit. We attempt to flush other buffer
1860
 
                        pools based on the assumption that it will
1861
 
                        help in the retry which will follow the
1862
 
                        failure. */
1863
 
                        skipped = TRUE;
1864
 
 
1865
 
                        continue;
1866
 
                }
1867
 
 
1868
 
                page_count = buf_flush_batch(
1869
 
                        buf_pool, BUF_FLUSH_LIST, min_n, lsn_limit);
1870
 
 
1871
 
                buf_flush_end(buf_pool, BUF_FLUSH_LIST);
1872
 
 
1873
 
                buf_flush_common(BUF_FLUSH_LIST, page_count);
1874
 
 
1875
 
                total_page_count += page_count;
1876
 
        }
1877
 
 
1878
 
        return(lsn_limit != IB_ULONGLONG_MAX && skipped
1879
 
               ? ULINT_UNDEFINED : total_page_count);
1880
 
}
1881
 
 
 
1166
        enum buf_flush  type)   /*!< in: BUF_FLUSH_LRU or BUF_FLUSH_LIST */
 
1167
{
 
1168
        ut_ad((type == BUF_FLUSH_LRU) || (type == BUF_FLUSH_LIST));
 
1169
 
 
1170
        os_event_wait(buf_pool->no_flush[type]);
 
1171
}
 
1172
 
1882
1173
/******************************************************************//**
1883
1174
Gives a recommendation of how many blocks should be flushed to establish
1884
1175
a big enough margin of replaceable blocks near the end of the LRU list
1887
1178
LRU list */
1888
1179
static
1889
1180
ulint
1890
 
buf_flush_LRU_recommendation(
1891
 
/*=========================*/
1892
 
        buf_pool_t*     buf_pool)               /*!< in: Buffer pool instance */
 
1181
buf_flush_LRU_recommendation(void)
 
1182
/*==============================*/
1893
1183
{
1894
1184
        buf_page_t*     bpage;
1895
1185
        ulint           n_replaceable;
1896
1186
        ulint           distance        = 0;
1897
1187
 
1898
 
        buf_pool_mutex_enter(buf_pool);
 
1188
        buf_pool_mutex_enter();
1899
1189
 
1900
1190
        n_replaceable = UT_LIST_GET_LEN(buf_pool->free);
1901
1191
 
1902
1192
        bpage = UT_LIST_GET_LAST(buf_pool->LRU);
1903
1193
 
1904
1194
        while ((bpage != NULL)
1905
 
               && (n_replaceable < BUF_FLUSH_FREE_BLOCK_MARGIN(buf_pool)
1906
 
                   + BUF_FLUSH_EXTRA_MARGIN(buf_pool))
1907
 
               && (distance < BUF_LRU_FREE_SEARCH_LEN(buf_pool))) {
 
1195
               && (n_replaceable < BUF_FLUSH_FREE_BLOCK_MARGIN
 
1196
                   + BUF_FLUSH_EXTRA_MARGIN)
 
1197
               && (distance < BUF_LRU_FREE_SEARCH_LEN)) {
1908
1198
 
1909
1199
                mutex_t* block_mutex = buf_page_get_mutex(bpage);
1910
1200
 
1921
1211
                bpage = UT_LIST_GET_PREV(LRU, bpage);
1922
1212
        }
1923
1213
 
1924
 
        buf_pool_mutex_exit(buf_pool);
 
1214
        buf_pool_mutex_exit();
1925
1215
 
1926
 
        if (n_replaceable >= BUF_FLUSH_FREE_BLOCK_MARGIN(buf_pool)) {
 
1216
        if (n_replaceable >= BUF_FLUSH_FREE_BLOCK_MARGIN) {
1927
1217
 
1928
1218
                return(0);
1929
1219
        }
1930
1220
 
1931
 
        return(BUF_FLUSH_FREE_BLOCK_MARGIN(buf_pool)
1932
 
               + BUF_FLUSH_EXTRA_MARGIN(buf_pool)
 
1221
        return(BUF_FLUSH_FREE_BLOCK_MARGIN + BUF_FLUSH_EXTRA_MARGIN
1933
1222
               - n_replaceable);
1934
1223
}
1935
1224
 
1941
1230
immediately, without waiting. */
1942
1231
UNIV_INTERN
1943
1232
void
1944
 
buf_flush_free_margin(
1945
 
/*==================*/
1946
 
        buf_pool_t*     buf_pool)               /*!< in: Buffer pool instance */
 
1233
buf_flush_free_margin(void)
 
1234
/*=======================*/
1947
1235
{
1948
1236
        ulint   n_to_flush;
 
1237
        ulint   n_flushed;
1949
1238
 
1950
 
        n_to_flush = buf_flush_LRU_recommendation(buf_pool);
 
1239
        n_to_flush = buf_flush_LRU_recommendation();
1951
1240
 
1952
1241
        if (n_to_flush > 0) {
1953
 
                ulint   n_flushed;
1954
 
 
1955
 
                n_flushed = buf_flush_LRU(buf_pool, n_to_flush);
1956
 
 
 
1242
                n_flushed = buf_flush_batch(BUF_FLUSH_LRU, n_to_flush, 0);
1957
1243
                if (n_flushed == ULINT_UNDEFINED) {
1958
1244
                        /* There was an LRU type flush batch already running;
1959
1245
                        let us wait for it to end */
1960
1246
 
1961
 
                        buf_flush_wait_batch_end(buf_pool, BUF_FLUSH_LRU);
 
1247
                        buf_flush_wait_batch_end(BUF_FLUSH_LRU);
1962
1248
                }
1963
1249
        }
1964
1250
}
1965
1251
 
1966
 
/*********************************************************************//**
1967
 
Flushes pages from the end of all the LRU lists. */
1968
 
UNIV_INTERN
1969
 
void
1970
 
buf_flush_free_margins(void)
1971
 
/*========================*/
1972
 
{
1973
 
        ulint   i;
1974
 
 
1975
 
        for (i = 0; i < srv_buf_pool_instances; i++) {
1976
 
                buf_pool_t*     buf_pool;
1977
 
 
1978
 
                buf_pool = buf_pool_from_array(i);
1979
 
 
1980
 
                buf_flush_free_margin(buf_pool);
1981
 
        }
1982
 
}
1983
 
 
1984
1252
/*********************************************************************
1985
1253
Update the historical stats that we are collecting for flush rate
1986
1254
heuristics at the end of each interval.
2041
1309
buf_flush_get_desired_flush_rate(void)
2042
1310
/*==================================*/
2043
1311
{
2044
 
        ulint           i;
2045
 
        lint            rate;
2046
 
        ulint           redo_avg;
2047
 
        ulint           n_dirty = 0;
2048
 
        ulint           n_flush_req;
2049
 
        ulint           lru_flush_avg;
2050
 
        ib_uint64_t     lsn = log_get_lsn();
2051
 
        ulint           log_capacity = log_get_capacity();
 
1312
        ulint                   redo_avg;
 
1313
        ulint                   lru_flush_avg;
 
1314
        ulint                   n_dirty;
 
1315
        ulint                   n_flush_req;
 
1316
        lint                    rate;
 
1317
        ib_uint64_t             lsn = log_get_lsn();
 
1318
        ulint                   log_capacity = log_get_capacity();
2052
1319
 
2053
1320
        /* log_capacity should never be zero after the initialization
2054
1321
        of log subsystem. */
2055
1322
        ut_ad(log_capacity != 0);
2056
1323
 
2057
1324
        /* Get total number of dirty pages. It is OK to access
2058
 
        flush_list without holding any mutex as we are using this
 
1325
        flush_list without holding any mtex as we are using this
2059
1326
        only for heuristics. */
2060
 
        for (i = 0; i < srv_buf_pool_instances; i++) {
2061
 
                buf_pool_t*     buf_pool;
2062
 
 
2063
 
                buf_pool = buf_pool_from_array(i);
2064
 
                n_dirty += UT_LIST_GET_LEN(buf_pool->flush_list);
2065
 
        }
 
1327
        n_dirty = UT_LIST_GET_LEN(buf_pool->flush_list);
2066
1328
 
2067
1329
        /* An overflow can happen if we generate more than 2^32 bytes
2068
1330
        of redo in this interval i.e.: 4G of redo in 1 second. We can
2104
1366
@return TRUE if ok */
2105
1367
static
2106
1368
ibool
2107
 
buf_flush_validate_low(
2108
 
/*===================*/
2109
 
        buf_pool_t*     buf_pool)               /*!< in: Buffer pool instance */
 
1369
buf_flush_validate_low(void)
 
1370
/*========================*/
2110
1371
{
2111
 
        buf_page_t*             bpage;
2112
 
        const ib_rbt_node_t*    rnode = NULL;
2113
 
 
2114
 
        ut_ad(buf_flush_list_mutex_own(buf_pool));
 
1372
        buf_page_t*     bpage;
2115
1373
 
2116
1374
        UT_LIST_VALIDATE(list, buf_page_t, buf_pool->flush_list,
2117
1375
                         ut_ad(ut_list_node_313->in_flush_list));
2118
1376
 
2119
1377
        bpage = UT_LIST_GET_FIRST(buf_pool->flush_list);
2120
1378
 
2121
 
        /* If we are in recovery mode i.e.: flush_rbt != NULL
2122
 
        then each block in the flush_list must also be present
2123
 
        in the flush_rbt. */
2124
 
        if (UNIV_LIKELY_NULL(buf_pool->flush_rbt)) {
2125
 
                rnode = rbt_first(buf_pool->flush_rbt);
2126
 
        }
2127
 
 
2128
1379
        while (bpage != NULL) {
2129
1380
                const ib_uint64_t om = bpage->oldest_modification;
2130
 
 
2131
 
                ut_ad(buf_pool_from_bpage(bpage) == buf_pool);
2132
 
 
2133
1381
                ut_ad(bpage->in_flush_list);
2134
 
 
2135
 
                /* A page in flush_list can be in BUF_BLOCK_REMOVE_HASH
2136
 
                state. This happens when a page is in the middle of
2137
 
                being relocated. In that case the original descriptor
2138
 
                can have this state and still be in the flush list
2139
 
                waiting to acquire the flush_list_mutex to complete
2140
 
                the relocation. */
2141
 
                ut_a(buf_page_in_file(bpage)
2142
 
                     || buf_page_get_state(bpage) == BUF_BLOCK_REMOVE_HASH);
 
1382
                ut_a(buf_page_in_file(bpage));
2143
1383
                ut_a(om > 0);
2144
1384
 
2145
 
                if (UNIV_LIKELY_NULL(buf_pool->flush_rbt)) {
2146
 
                        buf_page_t** prpage;
2147
 
 
2148
 
                        ut_a(rnode);
2149
 
                        prpage = rbt_value(buf_page_t*, rnode);
2150
 
 
2151
 
                        ut_a(*prpage);
2152
 
                        ut_a(*prpage == bpage);
2153
 
                        rnode = rbt_next(buf_pool->flush_rbt, rnode);
2154
 
                }
2155
 
 
2156
1385
                bpage = UT_LIST_GET_NEXT(list, bpage);
2157
1386
 
2158
1387
                ut_a(!bpage || om >= bpage->oldest_modification);
2159
1388
        }
2160
1389
 
2161
 
        /* By this time we must have exhausted the traversal of
2162
 
        flush_rbt (if active) as well. */
2163
 
        ut_a(rnode == NULL);
2164
 
 
2165
1390
        return(TRUE);
2166
1391
}
2167
1392
 
2170
1395
@return TRUE if ok */
2171
1396
UNIV_INTERN
2172
1397
ibool
2173
 
buf_flush_validate(
2174
 
/*===============*/
2175
 
        buf_pool_t*     buf_pool)       /*!< buffer pool instance */
 
1398
buf_flush_validate(void)
 
1399
/*====================*/
2176
1400
{
2177
1401
        ibool   ret;
2178
1402
 
2179
 
        buf_flush_list_mutex_enter(buf_pool);
2180
 
 
2181
 
        ret = buf_flush_validate_low(buf_pool);
2182
 
 
2183
 
        buf_flush_list_mutex_exit(buf_pool);
 
1403
        buf_pool_mutex_enter();
 
1404
 
 
1405
        ret = buf_flush_validate_low();
 
1406
 
 
1407
        buf_pool_mutex_exit();
2184
1408
 
2185
1409
        return(ret);
2186
1410
}