MDEV-21117 had to relax own events acceptance condition for a case
when a former semisync master server recovers after crash as the
semisync slave. That however admitted a possibility for endless event
"orbiting" in the non-strict slave gtid mode of semisync circular
setup.
The same server-id event termination is restored now for
the non-strict gtid mode to follow regular rules (that is it's ignored
unless @@global.replicate_same_server_id allows it in).
To address MDEV-21117 recovery agenda,
in the strict gtid mode and the transaction's gtid ordered strictly
greater than the current slave gtid state, the same server-id
transaction is accepted.
The gtid strict mode is safe to accept transactions even if
the slave state were not set correct by the user, e.g
at the former master.
An added test shows a typical out-of-order error at execution so
no data corruption is guaranteed in such a case.
DEBUG_SYNC signals can get lost in certain tests due to later
DEBUG_SYNC commands overwriting them. This patch addresses
these issues in three tests: main.query_cache_debug,
main.partition_debug_sync, and
rpl.rpl_dump_request_retry_warning.
Additionally, main.partition_debug_sync needed changes to the
result file (the others did not). The synchronization happened
between two commands, one based on ALTER, the other on DROP.
A new thread/connection was needed to synchronize the DEBUG_SYNC
actions between these commands, thereby changing the result file.
Additional comments were added for clarification.
Reviewed By:
============
Andrei Elkin <andrei.elkin@mariadb.com>
The rpl.rpl_seconds_behind_master_spike test would sometimes
timeout or take a very long time to complete. This happened
because an MTR DEBUG_SYNC signal would be lost due to a
subsequent call to RESET. I.e., the slave SQL thread would
be paused due to the WAIT_FOR signal being lost, resulting in
either a failed test if the `select master_pos_wait` timeout
occurs first, or a very long run-time if the DBUG_SYNC timeout
occurs first.
The fix ensures that the MTR signal is processed by the slave
SQL thread before issuing the call to RESET
Reviewed By:
============
Andrei Elkin <andrei.elkin@mariadb.com>
The test could fail sporadically because of not anticipated
race on slave between CREATE and ALTER queries.
Fixed to synchronize slave and master wrt CREATE.
This commit implements two phase binloggable ALTER.
When a new
@@session.binlog_alter_two_phase = YES
ALTER query gets logged in two parts, the START ALTER and the COMMIT
or ROLLBACK ALTER. START Alter is written in binlog as soon as
necessary locks have been acquired for the table. The timing is
such that any concurrent DML:s that update the same table are either
committed, thus logged into binary log having done work on the old
version of the table, or will be queued for execution on its new
version.
The "COMPLETE" COMMIT or ROLLBACK ALTER are written at the very point
of a normal "single-piece" ALTER that is after the most of
the query work is done. When its result is positive COMMIT ALTER is
written, otherwise ROLLBACK ALTER is written with specific error
happened after START ALTER phase.
Replication of two-phase binloggable ALTER is
cross-version safe. Specifically the OLD slave merely does not
recognized the start alter part, still being able to process and
memorize its gtid.
Two phase logged ALTER is read from binlog by mysqlbinlog to produce
BINLOG 'string', where 'string' contains base64 encoded
Query_log_event containing either the start part of ALTER, or a
completion part. The Query details can be displayed with `-v` flag,
similarly to ROW format events. Notice, mysqlbinlog output containing
parts of two-phase binloggable ALTER is processable correctly only by
binlog_alter_two_phase server.
@@log_warnings > 2 can reveal details of binlogging and slave side
processing of the ALTER parts.
The current commit also carries fixes to the following list of
reported bugs:
MDEV-27511, MDEV-27471, MDEV-27349, MDEV-27628, MDEV-27528.
Thanks to all people involved into early discussion of the feature
including Kristian Nielsen, those who helped to design, implement and
test: Sergei Golubchik, Andrei Elkin who took the burden of the
implemenation completion, Sujatha Sivakumar, Brandon
Nesterenko, Alice Sherepa, Ramesh Sivaraman, Jan Lindstrom.
New Feature:
===========
This commit extends the mariadb-binlog capabilities to allow events
to be filtered by GTID ranges. More specifically, the
--start-position and --stop-position arguments have been extended to
accept values formatted as a list of GTID positions, e.g.
--start-position=0-1-0,1-2-55. The following specific capabilities
are addressed:
1) GTIDs can be used to filter results on local binlog files
2) GTIDs can be used to filter results from remote servers
3) Implemented --gtid-strict-mode that ensures the GTID event
stream in each domain is monotonically increasing
4) Added new level of verbosity in mysqlbinlog -vvv to print
additional diagnostic information/warnings about invalid GTID
states
5) For a given GTID range, its start and stop position parameters
aim to mimic the behaviors of
CHANGE MASTER TO MASTER_USE_GTID=slave_pos and
START SLAVE UNTIL master_gtid_pos=<GTID>, respectively. In
particular, the start-position list expresses a gtid state of
the server, similarly to how @@global.gtid_slave_pos expresses
the gtid state of a slave server when connecting to a master
with MASTER_USE_GTID=slave_pos.
The GTID start-position list is exclusive and the
stop-position list is inclusive. This allows users to receive
events strictly after those that they already have, and is
useful in cases of point in (logical) time recovery including
1) events were received out of order and should be re-sent, or
2) specifying the gtid state of a slave to get events newer
than their current state. If a seq_no is 0 for start-position,
it means to include the entirety of the domain. If a seq_no is
0 for stop-position, it means to exclude all events from that
domain. The GTIDs provided in a start position argument must
match with the GTID state of the first processed log (i.e.
those listed in the Gtid_list event). If a stop position is
provided, the events that are output are limited to only those
with domain ids listed in the argument. When specifying
combinations of start and stop positions, the following
behaviors are expected:
[--start-position without --stop-position]: Events that have domain
ids in the start position are output if their seq_no occurs after
the respective start position. Events with domain ids that are
unspecified in the start position list are also output. Note that if
the Gtid_list event of the first binary log is populated (i.e.
non-empty), each domain in the Gtid_list must be present in the
start-position list with a seq_no at or after the listed value.
This behavior mimics how a slave only processes events after the
state provided by @@global.gtid_slave_pos when connecting to a
master with CHANGE MASTER TO MASTER_USE_GTID=slave_pos.
[--stop-position without --start-position]: Output is limited to
only events with both 1) domain ids that are present in the given
stop position list and 2) seq_nos that are less than or equal to
their respective stop GTID. Once all GTIDs in the stop position
list have been processed, the program will stop processing log
files. This behavior mimics how
START SLAVE UNTIL master_gtid_pos=<G>
has a slave only process events with domain ids present in G with
their seq_nos at or before the respective gtid.
[--start-position and --stop-position]: Output consists of the
intersection between the events permitted by both the start and stop
position rules. More concretely, the output can be defined by a
union of the following rules:
1. For domains which exist in both the start and stop position
lists, the events which exist in-between these positions
(exclusive start, inclusive stop) are output
2. For all other events, the rules of
[--stop-position without --start-position] are followed
This is due to the implicit filtering within each individual rule.
Even though the start position rule always includes events from
unspecified domains, the stop position rule takes precedence because
it always excludes events from unspecified domains. In other words,
events which the start position rule would have included would then
always be excluded by the stop position rule.
[neither --start-position nor --stop-position]: Events are not
omitted based on GTID positioning; however, --gtid-strict-mode and
-vvv can still analyze gtid correctness for warning and error
reporting.
[repeated specification of --start-position or --stop-position]:
Subsequent specifications of start and stop positions completely
override previous ones. E.g., if invoked as
mysqlbinlog --start-position=<G1> --start-position=<G2> ...
All GTIDs specified in G1 are ignored and only those specified in G2
are used for the start position.
A few additional notes:
1) this commit squashes together the commits:
f4319661120e-78a9d49907ba
2) Changed rpl.rpl_blackhole_row_annotate test because it has
out of order GTIDs in its binlog, so I added
--skip-gtid-strict-mode
3) After all binlog events have been written, the session server
id and domain id are reset to their values in the global state
Reviewed By:
===========
Andrei Elkin: <andrei.elkin@mariadb.com>
This patch addresses two problems with
rpl.rpl_seconds_behind_master_spike
First, --sync_slave_with_master / select master_pos_wait
seems to have a bug where it will hang after all master
events have been executed.
This patch removes the sync_slave_with_master command from
the test, where it not required anyway as it is used to
declare explicit cleanup
Second, the test uses timestamps to ensure that the
Seconds_Behind_Master value does not point to a time too
far in the past. The checks of these timestamps were
too strict, because they could be slightly inconsistent
with the master and the SBM would be counted as invalid
when it was actually correct.
To fix this, a slight buffer was added to the check
to ensure the value is valid but still does not point
too far in the past
Reviewed By:
===========
Andrei Elkin <andrei.elkin@mariadb.com>
The 10.5 version of the patch.
Removing DEFAULT from INFORMATION_SCHEMA columns.
DEFAULT in read-only tables is rather meaningless.
Upgrade should go smoothly.
Also fixes:
MDEV-20254 Problems with EMPTY_STRING_IS_NULL and I_S tables
Removing DEFAULT from INFORMATION_SCHEMA columns.
DEFAULT in read-only tables is rather meaningless.
Upgrade should go smoothly.
Also fixes:
MDEV-20254 Problems with EMPTY_STRING_IS_NULL and I_S tables
Problem:
========
A slave’s relay log format description event is used when
calculating Seconds_Behind_Master (SBM). This forces the SBM
value to spike when processing these events, as their creation
date is set to the timestamp that the IO thread begins.
Solution:
========
When the slave generates a format description event, mark the
event as a relay log event so it does not update the
rli->last_master_timestamp variable.
Reviewed By:
============
Andrei Elkin <andrei.elkin@mariadb.com>
Rows_log_event::do_apply_event(): Correct the mistake that was made in
the merge 5f8561a6bc.
In Galera, the query cache will be invalidated near the end
of the function.