This bug was originally filed and fixed as Bug#12612184. The original
fix was buggy, and it was patched by Bug#12704861. Also that patch was
buggy (potentially breaking crash recovery), and both fixes were
reverted.
This fix was not ported to the built-in InnoDB of MySQL 5.1, because
the function signatures of many core functions are different from
InnoDB Plugin and later versions. The block allocation routines and
their callers would have to changed so that they handle block
descriptors instead of page frames.
When a record is updated so that its size grows, non-updated columns
can be selected for external (off-page) storage. The bug is that the
initially inserted updated record contains an all-zero BLOB pointer to
the field that was not updated. Only after the BLOB pages have been
allocated and written, the valid pointer can be written to the record.
Between the release of the page latch in mtr_commit(mtr) after
btr_cur_pessimistic_update() and the re-latching of the page in
btr_pcur_restore_position(), other threads can see the invalid BLOB
pointer consisting of 20 zero bytes. Moreover, if the system crashes
at this point, the situation could persist after crash recovery, and
the contents of the non-updated column would be permanently lost.
The problem is amplified by the ROW_FORMAT=DYNAMIC and
ROW_FORMAT=COMPRESSED that were introduced in
innodb_file_format=barracuda in InnoDB Plugin, but the bug does exist
in all InnoDB versions.
The fix is as follows. After a pessimistic B-tree operation that needs
to write out off-page columns, allocate the pages for these columns in
the mini-transaction that performed the B-tree operation (btr_mtr),
but write the pages in a separate mini-transaction (blob_mtr). Do
mtr_commit(blob_mtr) before mtr_commit(btr_mtr). A quirk: Do not reuse
pages that were previously freed in btr_mtr. Only write the off-page
columns to 'fresh' pages.
In this way, crash recovery will see redo log entries for blob_mtr
before any redo log entry for btr_mtr. It will apply the BLOB page
writes to pages that were marked free at that point. If crash recovery
fails to see all of the btr_mtr redo log, there will be some
unreachable BLOB data in free pages, but the B-tree will be in a
consistent state.
btr_page_alloc_low(): Renamed from btr_page_alloc(). Add the parameter
init_mtr. Return an allocated block, or NULL. If init_mtr!=mtr but
the page was already X-latched in mtr, do not initialize the page.
btr_page_alloc(): Wrapper for btr_page_alloc_for_ibuf() and
btr_page_alloc_low().
btr_page_free(): Add a debug assertion that the page was a B-tree page.
btr_lift_page_up(): Return the father block.
btr_compress(), btr_cur_compress_if_useful(): Add the parameter ibool
adjust, for adjusting the cursor position.
btr_cur_pessimistic_update(): Preserve the cursor position when
big_rec will be written and the new flag BTR_KEEP_POS_FLAG is defined.
Remove a duplicate rec_get_offsets() call. Keep the X-latch on
index->lock when big_rec is needed.
btr_store_big_rec_extern_fields(): Replace update_inplace with
an operation code, and local_mtr with btr_mtr. When not doing a
fresh insert and btr_mtr has freed pages, put aside any pages that
were previously X-latched in btr_mtr, and free the pages after
writing out all data. The data must be written to 'fresh' pages,
because btr_mtr will be committed and written to the redo log after
the BLOB writes have been written to the redo log.
btr_blob_op_is_update(): Check if an operation passed to
btr_store_big_rec_extern_fields() is an update or insert-by-update.
fseg_alloc_free_page_low(), fsp_alloc_free_page(),
fseg_alloc_free_extent(), fseg_alloc_free_page_general(): Add the
parameter init_mtr. Return an allocated block, or NULL. If
init_mtr!=mtr but the page was already X-latched in mtr, do not
initialize the page.
xdes_get_descriptor_with_space_hdr(): Assert that the file space
header is being X-latched.
fsp_alloc_from_free_frag(): Refactored from fsp_alloc_free_page().
fsp_page_create(): New function, for allocating, X-latching and
potentially initializing a page. If init_mtr!=mtr but the page was
already X-latched in mtr, do not initialize the page.
fsp_free_page(): Add ut_ad(0) to the error outcomes.
fsp_free_page(), fseg_free_page_low(): Increment mtr->n_freed_pages.
fsp_alloc_seg_inode_page(), fseg_create_general(): Assert that the
page was not previously X-latched in the mini-transaction. A file
segment or inode page should never be allocated in the middle of an
mini-transaction that frees pages, such as btr_cur_pessimistic_delete().
fseg_alloc_free_page_low(): If the hinted page was allocated, skip the
check if the tablespace should be extended. Return NULL instead of
FIL_NULL on failure. Remove the flag frag_page_allocated. Instead,
return directly, because the page would already have been initialized.
fseg_find_free_frag_page_slot() would return ULINT_UNDEFINED on error,
not FIL_NULL. Correct a bogus assertion.
fseg_alloc_free_page(): Redefine as a wrapper macro around
fseg_alloc_free_page_general().
buf_block_buf_fix_inc(): Move the definition from the buf0buf.ic to
buf0buf.h, so that it can be called from other modules.
mtr_t: Add n_freed_pages (number of pages that have been freed).
page_rec_get_nth_const(), page_rec_get_nth(): The inverse function of
page_rec_get_n_recs_before(), get the nth record of the record
list. This is faster than iterating the linked list. Refactored from
page_get_middle_rec().
trx_undo_rec_copy(): Add a debug assertion for the length.
trx_undo_add_page(): Return a block descriptor or NULL instead of a
page number or FIL_NULL.
trx_undo_report_row_operation(): Add debug assertions.
trx_sys_create_doublewrite_buf(): Assert that each page was not
previously X-latched.
page_cur_insert_rec_zip_reorg(): Make use of page_rec_get_nth().
row_ins_clust_index_entry_by_modify(): Pass BTR_KEEP_POS_FLAG, so that
the repositioning of the cursor can be avoided.
row_ins_index_entry_low(): Add DEBUG_SYNC points before and after
writing off-page columns. If inserting by updating a delete-marked
record, do not reposition the cursor or commit the mini-transaction
before writing the off-page columns.
row_build(): Tighten a debug assertion about null BLOB pointers.
row_upd_clust_rec(): Add DEBUG_SYNC points before and after writing
off-page columns. Do not reposition the cursor or commit the
mini-transaction before writing the off-page columns.
rb:939 approved by Jimmy Yang
Bug#12612184 RACE CONDITION AFTER BTR_CUR_PESSIMISTIC_UPDATE()
The fix introduced potentially more severe crash recovery problems
than the bug causes. Revert the fix for now.
The title of the bug is a little confusing. The actual fix is to
reintroduce random readahead inside InnoDB with a dynamic, global
switch innodb_random_read_ahead [default = off].
Approved by: Sunny Bains
rb://696
approved by: Marko
rb://681
Coalescing of free buf_page_t descriptors can prove to be one severe
bottleneck in performance of compression. One such workload where it
hurts badly is DROP TABLE. This patch removes buf_page_t allocations
from buf_buddy and uses ut_malloc instead.
In order to further reduce overhead of colaescing we no longer attempt
to coalesce a block if the corresponding free_list is less than 16 in
size.
btr_cur_compress_if_useful(), btr_compress(): Add the parameter ibool
adjust. If adjust=TRUE, adjust the cursor position after compressing
the page.
btr_lift_page_up(): Return a pointer to the father page.
BTR_KEEP_POS_FLAG: A new flag for btr_cur_pessimistic_update().
btr_cur_pessimistic_update(): If *big_rec != NULL and flags &
BTR_KEEP_POS_FLAG, keep the cursor positioned on the updated record.
Also, do not release the index tree x-lock if *big_rec != NULL.
btr_cur_mtr_commit_and_start(): Commits and restarts a
mini-transaction so that it will retain an x-lock on index->lock and
the page of the cursor. This is invoked when
btr_cur_pessimistic_update() returns *big_rec != NULL.
In all callers of btr_cur_pessimistic_update() that do not pass
BTR_KEEP_POS_FLAG, assert that *big_rec == NULL.
btr_cur_compress(): Unused function [in the built-in MySQL 5.1], remove.
page_rec_get_nth(): Return the nth record on the page (an inverse
function of page_rec_get_n_recs_before()). Refactored from
page_get_middle_rec().
page_get_middle_rec(): Invoke page_rec_get_nth().
page_cur_insert_rec_zip_reorg(): Make use of the page directory
shortcuts in page_rec_get_nth() instead of scanning the whole list of
records.
row_ins_clust_index_entry_by_modify(): Pass BTR_KEEP_POS_FLAG to
btr_cur_pessimistic_update().
row_ins_index_entry_low(): If row_ins_clust_index_entry_by_modify()
returns a big_rec, invoke btr_cur_mtr_commit_and_start() in order to
commit and start the mini-transaction without releasing the x-locks on
index->lock and the cursor page, and write the big_rec. Releasing the
page latch in mtr_commit() caused a race condition.
row_upd_clust_rec(): Pass BTR_KEEP_POS_FLAG to
btr_cur_pessimistic_update(). If it returns a big_rec, invoke
btr_cur_mtr_commit_and_start() in order to commit and start the
mini-transaction without releasing the x-locks on index->lock and the
cursor page, and write the big_rec. Releasing the page latch in
mtr_commit() caused a race condition.
sync_thread_add_level(): Add the parameter ibool relock. When TRUE,
bypass the latching order rules.
rw_lock_add_debug_info(): For nested X-lock requests, pass relock=TRUE
to sync_thread_add_level().
rb:678 approved by Jimmy Yang
buf_block_alloc(): ulint zip_size is always 0.
buf_LRU_get_free_block(): ulint zip_size is always 0.
buf_LRU_free_block(): ibool* buf_pool_mutex_released is always NULL.
Remove these parameters.
buf_LRU_get_free_block(): Simplify the initialization of block->page.zip
and release buf_pool_mutex() earlier.
Detailed revision comments:
r6891 | vdimov | 2010-03-26 16:19:01 +0200 (Fri, 26 Mar 2010) | 5 lines
Non-functional change: update copyright year to 2010 of the files
that have been modified after 2010-01-01 according to svn.
for f in $(svn log -v -r{2010-01-01}:HEAD |grep "^ M " |cut -b 16- |sort -u) ; do sed -i "" -E 's/(Copyright \(c\) [0-9]{4},) [0-9]{4}, (.*Innobase Oy.+All Rights Reserved)/\1 2010, \2/' $f ; done
Detailed revision comments:
r6830 | marko | 2010-03-18 09:48:18 +0200 (Thu, 18 Mar 2010) | 3 lines
branches/zip: buf_page_peek_if_too_old(): Use 32-bit arithmetics
when comparing the age of access_time to buf_LRU_old_threshold_ms.
This fixes a bug on 64-bit systems.
Detailed revision comments:
r6798 | marko | 2010-03-11 09:53:01 +0200 (Thu, 11 Mar 2010) | 14 lines
branches/zip: Fix and clarify the latching of some buf_block_t members.
buf_block_t::check_index_page_at_flush: Note that this field is not
protected by any mutex. Make it a separate field, not a bitfield that
could share the machine word with other fields.
buf_block_t::lock_hash_val: Note that this field is protected by
buf_block_t::lock (or during block creation, by buf_pool_mutex and
buf_block_t::mutex).
buf_block_get_lock_hash_val(): Assert that block->lock is held by the
current thread.
Issue #465, rb://267 approved by Inaam Rana
Detailed revision comments:
r6110 | marko | 2009-10-29 12:44:57 +0200 (Thu, 29 Oct 2009) | 2 lines
branches/zip: Makefile.am (INCLUDES): Merge a change from MySQL:
Use $(srcdir)/include instead of $(top_srcdir)/storage/innobase/include.
r6111 | marko | 2009-10-29 13:04:11 +0200 (Thu, 29 Oct 2009) | 33 lines
branches/zip: Fix corruption of buf_pool->LRU_old and improve debug assertions.
This was reported as Issue #381.
buf_page_set_old(): Assert that blocks may only be set old if
buf_pool->LRU_old is initialized and buf_pool->LRU_old_len is nonzero.
Assert that buf_pool->LRU_old points to the block at the old/new boundary.
buf_LRU_old_adjust_len(): Invoke buf_page_set_old() after adjusting
buf_pool->LRU_old and buf_pool->LRU_old_len, in order not to violate
the added assertions.
buf_LRU_old_init(): Replace buf_page_set_old() with a direct
assignment to bpage->old, because these loops that initialize all the
blocks would temporarily violate the assertions about
buf_pool->LRU_old.
buf_LRU_remove_block(): When setting buf_pool->LRU_old = NULL, also
clear all bpage->old flags and set buf_pool->LRU_old_len = 0.
buf_LRU_add_block_to_end_low(), buf_LRU_add_block_low(): Move the
buf_page_set_old() call later in order not to violate the debug
assertions. If buf_pool->LRU_old is NULL, set old=FALSE.
buf_LRU_free_block(): Replace the UNIV_LRU_DEBUG assertion with a
dummy buf_page_set_old() call that performs more thorough checks.
buf_LRU_validate(): Do not tolerate garbage in buf_pool->LRU_old_len
even if buf_pool->LRU_old is NULL. Check that bpage->old is monotonic.
buf_relocate(): Make the UNIV_LRU_DEBUG checks stricter.
buf0buf.h: Revise the documentation of buf_page_t::old and
buf_pool_t::LRU_old_len.
Detailed revision comments:
r6107 | marko | 2009-10-28 16:10:34 +0200 (Wed, 28 Oct 2009) | 5 lines
branches/zip: buf_page_set_old(): Improve UNIV_LRU_DEBUG diagnostics
in order to catch the buf_pool->LRU_old corruption reported in Issue #381.
buf_LRU_old_init(): Set the property from the tail towards the front
of the buf_pool->LRU list, in order not to trip the debug check.
From revisions r5792 to r5864
Detailed revision comments:
r5792 | vasil | 2009-09-09 08:35:58 -0500 (Wed, 09 Sep 2009) | 32 lines
branches/zip:
Fix a bug in manipulating the variable innodb_old_blocks_pct:
for any value assigned it got that value -1, except for 75. When
assigned 75, it got 75.
mysql> set global innodb_old_blocks_pct=15;
Query OK, 0 rows affected (0.00 sec)
mysql> show variables like 'innodb_old_blocks_pct';
+-----------------------+-------+
| Variable_name | Value |
+-----------------------+-------+
| innodb_old_blocks_pct | 14 |
+-----------------------+-------+
1 row in set (0.00 sec)
mysql> set global innodb_old_blocks_pct=75;
Query OK, 0 rows affected (0.00 sec)
mysql> show variables like 'innodb_old_blocks_pct';
+-----------------------+-------+
| Variable_name | Value |
+-----------------------+-------+
| innodb_old_blocks_pct | 75 |
+-----------------------+-------+
After the fix it gets exactly what was assigned.
Approved by: Marko (via IM)
r5798 | calvin | 2009-09-09 10:28:10 -0500 (Wed, 09 Sep 2009) | 5 lines
branches/zip:
HA_ERR_TOO_MANY_CONCURRENT_TRXS is added in 5.1.38.
But the plugin should still work with previous versions
of MySQL.
r5804 | marko | 2009-09-10 00:29:31 -0500 (Thu, 10 Sep 2009) | 1 line
branches/zip: trx_cleanup_at_db_startup(): Fix a typo in comment.
r5822 | marko | 2009-09-10 05:10:20 -0500 (Thu, 10 Sep 2009) | 1 line
branches/zip: buf_page_release(): De-stutter the function comment.
r5825 | marko | 2009-09-10 05:47:09 -0500 (Thu, 10 Sep 2009) | 20 lines
branches/zip: Reduce mutex contention that was introduced when
addressing Bug #45015 (Issue #316), in r5703.
buf_page_set_accessed_make_young(): New auxiliary function, called by
buf_page_get_zip(), buf_page_get_gen(),
buf_page_optimistic_get_func(). Call ut_time_ms() outside of
buf_pool_mutex. Use cached access_time.
buf_page_set_accessed(): Add the parameter time_ms, so that
ut_time_ms() need not be called while holding buf_pool_mutex.
buf_page_optimistic_get_func(), buf_page_get_known_nowait(): Read
buf_page_t::access_time without holding buf_pool_mutex. This should be
OK, because the field is only used for heuristic purposes.
buf_page_peek_if_too_old(): If buf_pool->freed_page_clock == 0, return
FALSE, so that we will not waste time moving blocks in the LRU list in
the warm-up phase or when the workload fits in the buffer pool.
rb://156 approved by Sunny Bains
r5826 | marko | 2009-09-10 06:29:46 -0500 (Thu, 10 Sep 2009) | 12 lines
branches/zip: Roll back recovered dictionary transactions before
dropping incomplete indexes (Issue #337).
trx_rollback_or_clean_recovered(ibool all): New function, split from
trx_rollback_or_clean_all_recovered(). all==FALSE will only roll back
dictionary transactions.
recv_recovery_from_checkpoint_finish(): Call
trx_rollback_or_clean_recovered(FALSE) before
row_merge_drop_temp_indexes().
rb://158 approved by Sunny Bains
r5858 | vasil | 2009-09-11 12:46:47 -0500 (Fri, 11 Sep 2009) | 4 lines
branches/zip:
Fix the indentation of the closing bracket.
r5863 | vasil | 2009-09-12 02:07:08 -0500 (Sat, 12 Sep 2009) | 10 lines
branches/zip:
Check that pthread_t can indeed be passed to Solaris atomic functions, instead
of assuming that it can be passed if 0 can be assigned to it. It could be that:
* 0 can be assigned, but pthread_t cannot be passed and
* 0 cannot be assigned but pthread_t can be passed
Better to check what we are interested in, not something else and make
assumptions.
r5864 | vasil | 2009-09-12 02:22:55 -0500 (Sat, 12 Sep 2009) | 4 lines
branches/zip:
Include string.h which is needed for memset().
From revision r5748 to r5783
Detailed revision comments:
r5748 | marko | 2009-09-03 06:05:44 -0500 (Thu, 03 Sep 2009) | 1 line
branches/zip: MLOG_MULTI_REC_END: Correct the comment.
r5751 | marko | 2009-09-03 09:36:15 -0500 (Thu, 03 Sep 2009) | 7 lines
branches/zip: row_merge(): Remove a bogus debug assertion
that was triggered when creating an index on an empty table.
row_merge_sort(): Add debug assertions and comments that justify
the loop termination condition.
The bogus assertion ut_ad(ihalf > 0) was reported by Michael.
r5752 | marko | 2009-09-03 09:55:51 -0500 (Thu, 03 Sep 2009) | 10 lines
branches/zip: recv_recover_page_func(): Write the log sequence number
to the compressed page, if there is one. Previously, the function only
wrote the LSN to the uncompressed page.
It is not clear why recv_recover_page_func() is updating FIL_PAGE_LSN
in the buffer pool. The log sequence number will be stamped on the
page when it is flushed to disk, in buf_flush_init_for_writing().
I noticed this inconsistency when analyzing Issue #313, but this patch
does not fix it. That is no surprise, since FIL_PAGE_LSN should only
matter on disk files, not in the buffer pool.
r5775 | calvin | 2009-09-07 16:15:05 -0500 (Mon, 07 Sep 2009) | 13 lines
branches/zip: Build InnoDB on Windows with UNIV_HOTBACKUP
The changes are non-functional changes for normal InnoDB,
but needed for building the Hot Backup on Windows (with
UNIV_HOTBACKUP defined).
- Define os_aio_use_native_aio for HB.
- Do not acquire seek mutexes for backup since HB is single threaded.
- Do not use srv_flush_log_at_trx_commit for HB build
rb://155
Approved by: Marko
r5777 | marko | 2009-09-08 10:50:25 -0500 (Tue, 08 Sep 2009) | 2 lines
branches/zip: Remove BUF_LRU_INITIAL_RATIO, which should have been removed
together with buf_LRU_get_recent_limit().
r5779 | marko | 2009-09-09 01:17:19 -0500 (Wed, 09 Sep 2009) | 2 lines
branches/zip: buf_page_peek_if_too_old(): Make the bitmasking work when
buf_pool->freed_page_clock is wider than 32 bits.
r5780 | marko | 2009-09-09 01:50:50 -0500 (Wed, 09 Sep 2009) | 1 line
branches/zip: ut_time_ms(): Return ulint, not uint.
r5782 | marko | 2009-09-09 02:00:59 -0500 (Wed, 09 Sep 2009) | 2 lines
branches/zip: buf_page_peek_if_too_old(): Silence a compiler warning
that was introduced in r5779 on 32-bit systems.
r5783 | marko | 2009-09-09 02:25:00 -0500 (Wed, 09 Sep 2009) | 1 line
branches/zip: buf_page_is_accessed(): Correct the function comment.
From revision r5703 to r5716
Detailed revision comments:
r5703 | marko | 2009-08-27 02:25:00 -0500 (Thu, 27 Aug 2009) | 41 lines
branches/zip: Replace the constant 3/8 ratio that controls the LRU_old
size with the settable global variable innodb_old_blocks_pct. The
minimum and maximum values are 5 and 95 per cent, respectively. The
default is 100*3/8, in line with the old behavior.
ut_time_ms(): New utility function, to return the current time in
milliseconds. TODO: Is there a more efficient timestamp function, such
as rdtsc divided by a power of two?
buf_LRU_old_threshold_ms: New variable, corresponding to
innodb_old_blocks_time. The value 0 is the default behaviour: no
timeout before making blocks 'new'.
bpage->accessed, bpage->LRU_position, buf_pool->ulint_clock: Remove.
bpage->access_time: New field, replacing bpage->accessed. Protected by
buf_pool_mutex instead of bpage->mutex. Updated when a page is created
or accessed the first time in the buffer pool.
buf_LRU_old_ratio, innobase_old_blocks_pct: New variables,
corresponding to innodb_old_blocks_pct
buf_LRU_old_ratio_update(), innobase_old_blocks_pct_update(): Update
functions for buf_LRU_old_ratio, innobase_old_blocks_pct.
buf_page_peek_if_too_old(): Compare ut_time_ms() to bpage->access_time
if buf_LRU_old_threshold_ms && bpage->old. Else observe
buf_LRU_old_ratio and bpage->freed_page_clock.
buf_pool_t: Add n_pages_made_young, n_pages_not_made_young,
n_pages_made_young_old, n_pages_not_made_young, for statistics.
buf_print(): Display buf_pool->n_pages_made_young,
buf_pool->n_pages_not_made_young. This function is only for crash
diagnostics.
buf_print_io(): Display buf_pool->LRU_old_len and quantities derived
from buf_pool->n_pages_made_young, buf_pool->n_pages_not_made_young.
This function is invoked by SHOW ENGINE INNODB STATUS.
rb://129 approved by Heikki Tuuri. This addresses Bug #45015.
r5704 | marko | 2009-08-27 03:31:17 -0500 (Thu, 27 Aug 2009) | 32 lines
branches/zip: Fix a critical bug in fast index creation that could
corrupt the created indexes.
row_merge(): Make "half" an in/out parameter. Determine the offset of
half the output file. Copy the last blocks record-by-record instead of
block-by-block, so that the records can be counted. Check that the
input and output have matching n_rec.
row_merge_sort(): Do not assume that two blocks of size N are merged
into a block of size 2*N. The output block can be shorter than the
input if the last page of each input block is almost empty. Use an
accurate termination condition, based on the "half" computed by
row_merge().
row_merge_read(), row_merge_write(), row_merge_blocks(): Add debug output.
merge_file_t, row_merge_file_create(): Add n_rec, the number of records
in the merge file.
row_merge_read_clustered_index(): Update n_rec.
row_merge_blocks(): Update and check n_rec.
row_merge_blocks_copy(): New function, for copying the last blocks in
row_merge(). Update and check n_rec.
This bug was discovered with a user-supplied test case that creates an
index where the initial temporary file is 249 one-megabyte blocks and
the merged files become smaller. In the test, possible merge record
sizes are 10, 18, and 26 bytes.
rb://150 approved by Sunny Bains. This addresses Issue #320.
r5705 | marko | 2009-08-27 06:56:24 -0500 (Thu, 27 Aug 2009) | 11 lines
branches/zip: dict_index_find_cols(): On column name lookup failure,
return DB_CORRUPTION (HA_ERR_CRASHED) instead of abnormally
terminating the server. Also, disable the previously added diagnostic
output to the error log, because mysql-test-run does not like extra
output in the error log. (Bug #44571)
dict_index_add_to_cache(): Handle errors from dict_index_find_cols().
mysql-test/innodb_bug44571.test: A test case for triggering the bug.
rb://135 approved by Sunny Bains.
r5706 | inaam | 2009-08-27 11:00:27 -0500 (Thu, 27 Aug 2009) | 20 lines
branches/zip rb://147
Done away with following two status variables:
innodb_buffer_pool_read_ahead_rnd
innodb_buffer_pool_read_ahead_seq
Introduced two new status variables:
innodb_buffer_pool_read_ahead = number of pages read as part of
readahead since server startup
innodb_buffer_pool_read_ahead_evicted = number of pages that are read
in as readahead but were evicted before ever being accessed since
server startup i.e.: a measure of how badly our readahead is
performing
SHOW INNODB STATUS will show two extra numbers in buffer pool section:
pages read ahead/sec and pages evicted without access/sec
Approved by: Marko
r5707 | inaam | 2009-08-27 11:20:35 -0500 (Thu, 27 Aug 2009) | 6 lines
branches/zip
Remove unused macros as we erased the random readahead code in r5703.
Also fixed some comments.
r5708 | inaam | 2009-08-27 17:43:32 -0500 (Thu, 27 Aug 2009) | 4 lines
branches/zip
Remove redundant TRUE : FALSE from the return statement
r5709 | inaam | 2009-08-28 01:22:46 -0500 (Fri, 28 Aug 2009) | 5 lines
branches/zip rb://152
Disable display of deprecated parameter innodb_file_io_threads in
'show variables'.
r5714 | marko | 2009-08-31 01:10:10 -0500 (Mon, 31 Aug 2009) | 5 lines
branches/zip: buf_chunk_not_freed(): Do not acquire block->mutex unless
block->page.state == BUF_BLOCK_FILE_PAGE. Check that block->page.state
makes sense.
Approved by Sunny Bains over the IM.
r5716 | vasil | 2009-08-31 02:47:49 -0500 (Mon, 31 Aug 2009) | 9 lines
branches/zip:
Fix Bug#46718 InnoDB plugin incompatible with gcc 4.1 (at least: on PPC): "Undefined symbol"
by implementing our own check in plug.in instead of using the result from
the check from MySQL because it is insufficient.
Approved by: Marko (rb://154)
