There is an inherent race condition between Mariabackup and the
MariaDB server when the InnoDB redo log is being copied. It is
possible that the tail of the circular redo log is overwriting
the head of the log before Mariabackup gets a chance to read it.
So, we reduce the test to generate less redo log. Also, enable
the test on all supported innodb_page_size.
The option innodb_log_compressed_pages was contributed by
Facebook to MySQL 5.6. It was disabled in the 5.6.10 GA release
due to problems that were fixed in 5.6.11, which is when the
option was enabled.
The option was set to innodb_log_compressed_pages=ON by default
(disabling the feature), because safety was considered more
important than speed. The option innodb_log_compressed_pages=OFF
can *CORRUPT* ROW_FORMAT=COMPRESSED tables on crash recovery
if the zlib deflate function is behaving differently (producing
a different amount of compressed data) from how it behaved
when the redo log records were written (prior to the crash recovery).
In MDEV-6935, the default value was changed to
innodb_log_compressed_pages=OFF. This is inherently unsafe, because
there are very many different environments where MariaDB can be
running, using different zlib versions. While zlib can decompress
data just fine, there are no guarantees that different versions will
always compress the same data to the exactly same size. To avoid
problems related to zlib upgrades or version mismatch, we must
use a safe default setting.
This will reduce the write performance for users of
ROW_FORMAT=COMPRESSED tables. If you configure
innodb_log_compressed_pages=ON, please make sure that you will
always cleanly shut down InnoDB before upgrading the server
or zlib.
The test did not handle correctly possible difference in system
timezone. The fix is to remove non-functional setting of local
time_zone and instead allow timestamp replacement to work with
any date/time
when opening 10.1- table that has virtual columns:
1. don't error out if it has vcols over autoinc columns.
just issue a warning.
2. set vcol type properly
3. in innodb: use table->s->stored_fields instead of table->s->fields,
because that's what was stored in innodb data dictionary
On Windows, when tmpdir is not writable, there are only messages
like this:
2017-07-05 14:04:25 3860 [ERROR] InnoDB: Unable to create temporary file; errno: 0
On other platforms, there would be two messages for each failure:
2017-07-05 17:23:02 140436573771648 [ERROR] mysqld: Can't create/write to file '/dev/null/nonexistent/ibaajU4U' (Errcode: 20 "Not a directory")
2017-07-05 17:23:02 140436573771648 [ERROR] InnoDB: Unable to create temporary file; errno: 20
When using innodb_page_size=16k, InnoDB tables
that were created in MariaDB 10.1.0 to 10.1.20 with
PAGE_COMPRESSED=1 and
PAGE_COMPRESSION_LEVEL=2 or PAGE_COMPRESSION_LEVEL=3
would fail to load.
fsp_flags_is_valid(): When using innodb_page_size=16k, use a
more strict check for .ibd files, with the assumption that
nobody would try to use different-page-size files.
When using innodb_page_size=16k, InnoDB tables
that were created in MariaDB 10.1.0 to 10.1.20 with
PAGE_COMPRESSED=1 and
PAGE_COMPRESSION_LEVEL=2 or PAGE_COMPRESSION_LEVEL=3
would fail to load.
fsp_flags_is_valid(): When using innodb_page_size=16k, use a
more strict check for .ibd files, with the assumption that
nobody would try to use different-page-size files.
This is a regression caused by
commit bb60a832ed
srv_shutdown_all_bg_threads(): If os_thread_count indicates that
no threads are running, do not bother checking thread status.
This avoids a crash when InnoDB startup is aborted before
os_aio_init() has been invoked. (os_aio_all_slots_free() would
dereference AIO::s_reads even though it is NULL.)
InnoDB I/O and buffer pool interfaces and the redo log format
have been changed between MariaDB 10.1 and 10.2, and the backup
code has to be adjusted accordingly.
The code has been simplified, and many memory leaks have been fixed.
Instead of the file name xtrabackup_logfile, the file name ib_logfile0
is being used for the copy of the redo log. Unnecessary InnoDB startup and
shutdown and some unnecessary threads have been removed.
Some help was provided by Vladislav Vaintroub.
Parameters have been cleaned up and aligned with those of MariaDB 10.2.
The --dbug option has been added, so that in debug builds,
--dbug=d,ib_log can be specified to enable diagnostic messages
for processing redo log entries.
By default, innodb_doublewrite=OFF, so that --prepare works faster.
If more crash-safety for --prepare is needed, double buffering
can be enabled.
The parameter innodb_log_checksums=OFF can be used to ignore redo log
checksums in --backup.
Some messages have been cleaned up.
Unless --export is specified, Mariabackup will not deal with undo log.
The InnoDB mini-transaction redo log is not only about user-level
transactions; it is actually about mini-transactions. To avoid confusion,
call it the redo log, not transaction log.
We disable any undo log processing in --prepare.
Because MariaDB 10.2 supports indexed virtual columns, the
undo log processing would need to be able to evaluate virtual column
expressions. To reduce the amount of code dependencies, we will not
process any undo log in prepare.
This means that the --export option must be disabled for now.
This also means that the following options are redundant
and have been removed:
xtrabackup --apply-log-only
innobackupex --redo-only
In addition to disabling any undo log processing, we will disable any
further changes to data pages during --prepare, including the change
buffer merge. This means that restoring incremental backups should
reliably work even when change buffering is being used on the server.
Because of this, preparing a backup will not generate any further
redo log, and the redo log file can be safely deleted. (If the
--export option is enabled in the future, it must generate redo log
when processing undo logs and buffered changes.)
In --prepare, we cannot easily know if a partial backup was used,
especially when restoring a series of incremental backups. So, we
simply warn about any missing files, and ignore the redo log for them.
FIXME: Enable the --export option.
FIXME: Improve the handling of the MLOG_INDEX_LOAD record, and write
a test that initiates a backup while an ALGORITHM=INPLACE operation
is creating indexes or rebuilding a table. An error should be detected
when preparing the backup.
FIXME: In --incremental --prepare, xtrabackup_apply_delta() should
ensure that if FSP_SIZE is modified, the file size will be adjusted
accordingly.
CREATE/DROP TEMPORARY TABLE are not safe to optimistically replicate in
parallel with other transactions, so they need to be marked as "ddl" in the
binlog.
This was already done for stand-alone CREATE/DROP TEMPORARY. But temporary
tables can also be created and dropped inside a BEGIN...END transaction, and
such transactions were not marked as ddl. Nor was the DROP TEMPORARY TABLE
statement emitted implicitly when a client connection is closed.
So this patch adds such ddl mark for the missing cases.
The difference to Kristian's original patch is mainly a fix in
mysql_trans_commit_alter_copy_data() to remember the unsafe_rollback_flags
over the temporary commit.
Problem
-------
For one-statement contains multiple row events, Flashback didn't reverse the
sequence of row events inside one-statement.
Solution
--------
Using a new array 'events_in_stmt' to store the row events of one-statement,
when parsed the last one event, then print from the last one to the first one.
In the same time, fixed another bug, without -vv will not insert the table_map
into print_event_info->m_table_map, then change_to_flashback_event() will not
execute because of Table_map_log_event is empty.
Problem was that in a circular replication setup the master remembers
position to events it has generated itself when reading from a slave.
If there are no new events in the queue from the slave, a
Gtid_list_log_event is generated to remember the last skipped event.
The problem happens if there is a network delay and we generate a
Gtid_list_log_event in the middle of the transaction, in which case there
will be an implicit comment and a new transaction with serverid=0 will be
logged.
The fix was to not generate any Gtid_list_log_events in the middle of a
transaction.
- Added variable tmp_disk_table_size
- Added variable tmp_memory_table_size as an alias for tmp_table_size
- Changed internal variable tmp_table_size to tmp_memory_table_size
- create_info.data_file_length is now set with tmp_disk_table_size
- Fixed that Aria doesn't reset max_data_file_length for internal tables
- Added status flag if table is full so that we can detect this on next insert.
This ensures that the table is always 'correct', but we get the error one
row after the row that grow the table too big.
- Removed some mutex lock for internal temporary tables
The field fts_token->position is not initialized in
row_merge_fts_doc_tokenize(). We cannot have that field
without changing the fulltext parser plugin ABI
(adding st_mysql_ftparser_boolean_info::position,
as it was done in MySQL 5.7 in WL#6943).
The InnoDB fulltext parser plugins "ngram" and "Mecab" that were
introduced in MySQL 5.7 do depend on that field. But the simple_parser
does not. Apparently, simple_parser is leaving the field as 0.
So, in our fix we will assume that the missing position field is 0.
In Mariabackup, we would want the backed-up redo log file size to be
a multiple of 512 bytes, or OS_FILE_LOG_BLOCK_SIZE. However, at startup,
InnoDB would be picky, requiring the file size to be a multiple of
innodb_page_size.
Furthermore, InnoDB would require the parameter to be a multiple of
one megabyte, while the minimum granularity is 512 bytes. Because
the data-file-oriented fil_io() API is being used for writing the
InnoDB redo log, writes will for now require innodb_log_file_size to
be a multiple of the maximum innodb_page_size (65536 bytes).
To complicate matters, InnoDB startup divided srv_log_file_size by
UNIV_PAGE_SIZE, so that initially, the unit was bytes, and later it
was innodb_page_size. We will simplify this and keep srv_log_file_size
in bytes at all times.
innobase_log_file_size: Remove. Remove some obsolete checks against
overflow on 32-bit systems. srv_log_file_size is always 64 bits, and
the maximum size 512GiB in multiples of innodb_page_size always fits
in ulint (which is 32 or 64 bits). 512GiB would be 8,388,608*64KiB or
134,217,728*4KiB.
log_init(): Remove the parameter file_size that was always passed as
srv_log_file_size.
log_set_capacity(): Add a parameter for passing the requested file size.
srv_log_file_size_requested: Declare static in srv0start.cc.
create_log_file(), create_log_files(),
innobase_start_or_create_for_mysql(): Invoke fil_node_create()
with srv_log_file_size expressed in multiples of innodb_page_size.
innobase_start_or_create_for_mysql(): Require the redo log file sizes
to be multiples of 512 bytes.
trx_sys_print_mysql_binlog_offset(): Use 64-bit arithmetics and ib::info().
TRX_SYS_MYSQL_LOG_OFFSET: Replaces TRX_SYS_MYSQL_LOG_OFFSET_HIGH,
TRX_SYS_MYSQL_LOG_OFFSET_LOW.
trx_sys_update_mysql_binlog_offset(): Remove the constant parameter
field=TRX_SYS_MYSQL_LOG_INFO. Use 64-bit arithmetics.
Problem:- While running tests from wsrep suite , we include file have_wsrep.inc
or have_wsrep_enabled.inc , these file test wsrep plugin is ACTIVE or 'wsrep_on'
is ON. These select does not ensure that whether 'wsrep_ready' is ON , So that
we can process SQL queries. So sometimes we will get error like this
mysqltest: At line 81: query 'call mtr.check_testcase()' failed: 1047: WSREP has
not yet prepared node for application use not ok
Solution:- In file have_wsrep.inc and have_wsrep_enabled.inc we will include
wait_until_ready.inc , which will wait untill 'wsrep_on' is on
When it comes to DEFAULT values of columns, InnoDB is imposing both
unnecessary and insufficient conditions on whether ALGORITHM=INPLACE
should be allowed for ALTER TABLE.
When changing an existing column to NOT NULL, any NULL values in the
columns only get a special treatment if the column is changed to an
AUTO_INCREMENT column (which is not supported by ALGORITHM=INPLACE)
or the column type is TIMESTAMP. In all other cases, an error
must be reported for the failure to convert a NULL value to NOT NULL.
InnoDB was unnecessarily interested in whether the DEFAULT value
is not constant when altering other than TIMESTAMP columns. Also,
when changing a TIMESTAMP column to NOT NULL, InnoDB was performing
an insufficient check, and it was incorrectly allowing a constant
DEFAULT value while not being able to replace NULL values with that
constant value.
Furthermore, in ADD COLUMN, InnoDB is unnecessarily rejecting certain
nondeterministic DEFAULT expressions (depending on the session
parameters or the current time).
While the primary purpose of innodb_force_recovery is to allow
data to be rescued from an InnoDB instance that would crash due
to some data corruption, the settings 1, 2, or 3 are relatively
safe to use and there is no need to prevent write transactions
in these modes.
The setting innodb_force_recovery=4 and above can cause database
corruption. For those modes, we already set the flag
high_level_read_only to disable modifications, except DROP TABLE.
MODIFICATIONS_NOT_ALLOWED_MSG_FORCE_RECOVERY: Remove. There is no
need to spam the error log for each refused DML operation. It suffices
to return an error to the client. There will be messages at startup
if innodb_read_only or innodb_force_recovery are preventing writes.
Comment from Codership:-
To fix the problem, we changed the certification logic in galera to treat insert
on child table row as exclusive to prevent any operation on referenced
parent table row. At the same time, update and delete on
child table row were demoted to "shared", which makes it possible to
update/delete referenced parent table row, but only in a later transaction.
This change allows somewhat more concurrency for foreign key constrained
transactions, but is still safe for correct certification end result.
