The BtrBulk class, which was introduced in MySQL 5.7, is by design
the exclusive writer to an index. It is therefore unnecessary to
acquire the dict_index_t::lock in that code.
Holding the dict_index_t::lock would unnecessarily block other threads
(SQL connections and the InnoDB purge threads) from buffering concurrent
modifications to being-created secondary indexes.
This fix is motivated by a change in MySQL 5.7.28:
Bug #29008298 MYSQLD CRASHES ITSELF WHEN CREATING INDEX
mysql/mysql-server@f9fb96c20f
PageBulk::init(), PageBulk::latch(): Never acquire m_index->lock.
PageBulk::storeExt(): Remove some pointer indirection, and improve
a debug assertion that seems to prove that some code is redundant.
BtrBulk::pageCommit(): Assert that m_index->lock is not being held.
btr_blob_log_check_t: Do not acquire m_index->lock if
m_op == BTR_STORE_INSERT_BULK. Add UNIV_UNLIKELY hints around
that condition.
btr_store_big_rec_extern_fields(): Allow index->lock not to be held
while op == BTR_STORE_INSERT_BULK. Add UNIV_UNLIKELY hints around
that condition.
MDEV-18451 Server crashes in maria_create_trn_for_mysql
upon ALTER TABLE
Problem was that when table was locked many times, not all
instances where removed from the transaction by
_ma_remove_table_from_trnman()
Problem was in a combination of LOCK TABLES on several Aria
tables followed by an ALTER TABLE. After the ALTER TABLE there
was a force close + reopen of the alter table. The close failed
because the table was still part of a transaction.
Fixed by calling extra(HA_EXTRA_PREPARE_FOR_FORCED_CLOSE) as
part of closing the table, which ensures that the table is not
anymore part of the current transaction.
Proper C-style type erasure is done via void*, not via char* or something else.
free_key_cache()
free_rpl_filter(): types were fixed to avoid function pointer type cast which
is still undefined behavior.
Note, that casting from void* to any other pointer type is safe and correct.
fil_crypt_rotate_page(): Skip the key rotation for pages that carry 0
in FIL_PAGE_TYPE. This avoids not only unnecessary writes, but also
failures of the recently added debug assertion in
buf_flush_init_for_writing() that the FIL_PAGE_TYPE should be nonzero.
Note: the debug assertion can fail if the file was originally created
before MySQL 5.5. In old InnoDB versions, FIL_PAGE_TYPE was only
initialized for B-tree pages, to FIL_PAGE_INDEX. For any other pages,
the field could be garbage, including FIL_PAGE_INDEX. In MariaDB 10.2
and later, buf_flush_init_for_writing() would initialize the
FIL_PAGE_TYPE on such old pages, but only after passing the debug
assertion that insists that pages have a nonzero FIL_PAGE_TYPE.
Thus, the debug assertion at the start of buf_flush_init_for_writing()
can fail when upgrading from very old debug files. This assertion is
only present in debug builds, not release builds.
Old InnoDB/XtraDB versions only initialized FIL_PAGE_TYPE for
B-tree pages (to FIL_PAGE_INDEX), and left it uninitialized
(possibly containing FIL_PAGE_INDEX) for others. In MySQL
or MariaDB 5.5, the field is initialized on almost all pages,
but still not all of them.
In MariaDB 10.2 and later, buf_flush_init_for_writing() would
initialize the FIL_PAGE_TYPE on such old pages, but only after
passing the debug assertion that we are now removing from 10.1.
There, we will be able to modify fil_crypt_rotate_page() so
that it will skip the key rotation for pages that contain 0
in FIL_PAGE_TYPE.
In MariaDB 10.1, there is no logic that would initialize
FIL_PAGE_TYPE on data pages in old data files after an update.
So, encryption key rotation may routinely cause page flushes
on pages that contain 0 in FIL_PAGE_TYPE.
The assertion that was added in
commit c0c003beb4
to augment the fix of MDEV-20805 turns out to be invalid when
innodb_immediate_scrub_data_uncompressed is enabled.
In this mode, fsp_init_file_page() will be invoked on data pages
that have been freed, causing writes of almost-all-zero pages.
btr_page_free(): Adjust the comment.
buf_flush_init_for_writing(): Disable the assertion with a note
that it should be re-enabled in MDEV-15528.
When the mysqld_multi script passes the --defaults-group-suffix
option to mysqld, it must remove the initial substring with the
group name ("mysqld") from option value, because otherwise substring
"mysqld" will be added to the group name and then the group name
will contain the word "mysqld" twice, which is wrong, because
mysqld itself adds the suffix received to the group name.
When the mysqld_multi script passes the --defaults-group-suffix
option to mysqld, it must remove the initial substring with the
group name ("mysqld") from option value, because otherwise substring
"mysqld" will be added to the group name and then the group name
will contain the word "mysqld" twice, which is wrong, because
mysqld itself adds the suffix received to the group name.
This is another follow-up fix to
commit b393e2cb0c
which turned out to be still broken.
Replace the C++11 keyword 'constexpr' with #define.
debug_sync_t::str: Remove the zero-length array.
Replace sync->str with reinterpret_cast<char*>(&sync[1]).
Remove unused variables and type mismatch that was introduced
in commit b393e2cb0c
Also, fix a typo in the documentation of the parameter, and
update the test.
buf_flush_init_for_writing(): Assert that FIL_PAGE_TYPE is set
except when creating a new data file with a dummy first page.
buf_dblwr_create(): Ensure that FIL_PAGE_TYPE on all pages
will be initialized. Reset buf_dblwr_being_created at the end.
In the function recv_parse_or_apply_log_rec_body() there are debug checks
for validating the state of the page when redo log records are being
applied. Most notably, FIL_PAGE_TYPE should be set before anything else
is being written to the page.
ibuf_add_free_page(): Set FIL_PAGE_TYPE before performing any other changes.
Apply the correct pattern for debug instrumentation:
SET @save_dbug=@@debug_dbug;
SET debug_dbug='+d,...';
...
SET debug_dbug=@save_dbug;
Numerous tests use statements of the form
SET debug_dbug='-d,...';
which will inadvertently enable all DBUG tracing output,
causing unnecessary waste of resources.
The test main.index_merge_innodb is taking very much time,
especially on later versions (10.2 and 10.3).
Some of this could be attributed to the use of INSERT...SELECT,
which is time-consumingly creating explicit record locks in InnoDB
for the locking read in the SELECT part.
In 10.3 and later, some slowness can be attributed to MDEV-12288,
which makes the InnoDB purge thread spend time to reset transaction
identifiers in the inserted records. If we prevent purge from
running before all tables are dropped, the test seems to be
10% faster on an unoptimized debug build on 10.5. (A proper fix
would be to implement MDEV-515 and stop writing row-level undo log
records for inserts into an empty table or partition.)
At the same time, it should not hurt to make main.index_merge_myisam
to use the sequence engine. Not only could it be a little faster,
but the test would be slightly more readable.
In MDEV-11369 (instant ADD COLUMN) in MariaDB Server 10.3,
we introduced the hidden metadata record that must be the
first record in the clustered index if and only if
index->is_instant() holds.
To catch MDEV-19783, in
commit ed0793e096 and
commit 99dc40d6ac
we added some assertions to find cases where
the metadata record is missing while it should not be, or a
record exists when it should not. Those assertions were invalid
when traversing the PAGE_FREE list. That list can contain anything;
we must only be able to determine the successor and the size of
each garbage record in it.
page_validate(), page_simple_validate_old(), page_simple_validate_new():
Do not invoke page_rec_get_next_const() for traversing the PAGE_FREE
list, but instead use a lower-level accessor that does not attempt to
validate the REC_INFO_MIN_REC_FLAG.
page_copy_rec_list_end_no_locks(),
page_copy_rec_list_start(), page_delete_rec_list_start():
Add assertions.
btr_page_get_split_rec_to_left(): Remove a redundant return value,
and make the output parameter the return value.
btr_page_get_split_rec_to_right(), btr_page_split_and_insert(): Clean up.
btr_cur_pessimistic_delete(): code changed in a way that allows
to put more REC_INFO_MIN_REC_FLAG assertions inside btr_set_min_rec_mark().
Without that change tests innodb.innodb-table-online,
innodb.temp_table_savepoint and innodb_zip.prefix_index_liftedlimit fail.
Removed basically duplicated page_zip_validate() calls
which fails because of temporary(!) invariant violation.
That fixed innodb_zip.wl5522_debug_zip and
innodb_zip.prefix_index_liftedlimit
The bug affects MariaDB Server 10.3 or later, but it makes sense
to improve CHECK TABLE in earlier versions already.
page_validate(): Check REC_INFO_MIN_REC_FLAG in the records.
This allows CHECK TABLE to catch more bugs.
Until now, InnoDB inefficiently compared the aligned fields
FIL_PAGE_PREV, FIL_PAGE_NEXT to the byte-order-agnostic value FIL_NULL.
This is a backport of 32170f8c6d
from MariaDB Server 10.3.
Analysis
Mysqlbinlog output for encrypted binary log
#Q> insert into tab1 values (3,'row 003')
#190912 17:36:35 server id 10221 end_log_pos 980 CRC32 0x53bcb3d3 Table_map: `test`.`tab1` mapped to number 19
# at 940
#190912 17:36:35 server id 10221 end_log_pos 1026 CRC32 0xf2ae5136 Write_rows: table id 19 flags: STMT_END_F
Here we can see Table_map_log_event ends at 980 but Next event starts at 940.
And the reason for that is we do not send START_ENCRYPTION_EVENT to the slave
Solution:-
Send Start_encryption_log_event as Ignorable_log_event to slave(mysqlbinlog),
So that mysqlbinlog can update its log_pos.
Since Slave can request multiple FORMAT_DESCRIPTION_EVENT while master does not
have so We only update slave master pos when master actually have the
FORMAT_DESCRIPTION_EVENT. Similar logic should be applied for START_ENCRYPTION_EVENT.
Also added the test case when new server reads the data from old server which
does not send START_ENCRYPTION_EVENT to slave.
Master Slave Upgrade Scenario.
When Slave is updated first, Slave will have extra logic of handling
START_ENCRYPTION_EVENT But master willnot be sending START_ENCRYPTION_EVENT.
So there will be no issue.
When Master is updated first, It will send START_ENCRYPTION_EVENT to
slave , But slave will ignore this event in queue_event.
read_statistics_for_tables_if_needed
Regression after 279a907, read_statistics_for_tables_if_needed() was
called after open_normal_and_derived_tables() failure.
Fixed by moving read_statistics_for_tables() call to a branch of
get_schema_stat_record() where result of open_normal_and_derived_tables()
is checked.
Removed THD::force_read_stats, added read_statistics_for_tables() instead.
Simplified away statistics_for_command_is_needed().
When "--export" mariabackup option is used, mariabackup starts the server in
bootstrap mode to generate *.cfg files for the certain innodb tables.
The started instance of the server reads options from the file, pointed
out in "--defaults-file" mariabackup option.
If the server uses the same config file as mariabackup, and binlog is
switched on in that config file, then "mariabackup --prepare --export"
will create binary log files in the server's binary log directory, what
can cause issues.
The fix is to add "--skip-log-bin" in mysld options when the server is
started to generate *.cfg files.
For release builds, do not declare unused variables.
unpack_row(): Omit a debug-only variable from WSREP diagnostic message.
create_wsrep_THD(): Fix -Wmaybe-uninitialized for the PSI_thread_key.
Analysis:
========
In general if there are three groups.
1 - Inserts 32 which fails due to local entry '32' on slave.
2 - Inserts 33
3 - Inserts 34
Each group considers itself as a waiter and it waits for prior group 'waitee'.
This is done in 'register_wait_for_prior_event_group_commit'. If there is no
other parallel group being scheduled then no waitee will be there.
Let us assume 3 groups are being scheduled in parallel.
3-> waits for 2-> waits for->1
'1' upon completion it checks is there any registered subsequent waiter. If
so it wakes up the subsequent waiter with its execution status. This execution
status is stored in wakeup_error.
If '1' failed then it sends corresponding wakeup_error to 2. Then '2' aborts
and it propagates error to '3'. So all further commits are aborted. This
mechanism works only when all transactions reach a stage where they are
waiting for their prior commit to complete.
In case of optimistic following scenario occurs.
1,2,3 are scheduled in parallel.
3 - Reaches group_commit_code waits for 2 to complete.
1 - errors out sets stop_on_error_sub_id=1.
When a group execution results in error its corresponding sub_id is set to
'stop_on_error_sub_id'. Any new groups queued for execution will check if
their sub_id is > stop_on_error_sub_id. If it is true their execution will be
skipped as prior group execution failed. 'skip_event_group=1' will be set.
Since the execution of SQL thread is about to stop we just skip execution of
all the following event groups. We still do all the normal waiting and wakeup
processing between the event groups as a simple way to ensure that everything
is stopped and cleaned up correctly.
Upon error '1' transaction checks for registered waiters. Since no one is
there it simply goes away.
2 - Starts the execution. It checks do I have a waitee.
Since wait_commit_sub_id == entry->last_committed_sub_id no waitee is set.
Secondly: 'entry->stop_on_error_sub_id' is set by '1'st execution. Now
'handle_parallel_thread' code checks if the current group 'sub_id' is greater
than the 'sub_id' set within 'stop_on_error_sub_id'.
Since the above is true 'skip_event_group=true' is set. Simply call
'wait_for_prior_commit' to wakeup all waiters. Group '2' didn't had any
waitee and its execution is skipped. Hence its wakeup_error=0.It sends a
positive wakeup signal to '3'. Which commits. This results in a missed
transaction. i.e 33 is missed and 34 is committed.
Fix:
===
When a worker learns that an earlier transaction execution has failed, and it
should not proceed for further execution, it should mark its own execution
status as failed so that it alerts its followers to abort as well.
A syntax error in the mysqld_multi.sh script has been fixed
here + a "--defaults-group-suffix" option has been moved to
the top of the mysqld options list.
The test encryption.innodb-redo-badkey was accidentally disabled
until commit 23657a2101 enabled
it recently. Once it was enabled, it started failing randomly.
recv_recover_corrupt_page(): Do not assume that any redo log exists
for the page. A page may be unnecessarily read by read-ahead.
When noting the corruption, reset recv_addr->state to RECV_PROCESSED,
so that even if the same page is re-read again, we will only
decrement recv_sys->n_addrs once.
