CHANGE MASTER TO command required the value for RELAY_LOG_FILE to
be an absolute path, which was different from the requirement of
MASTER_LOG_FILE.
This patch fixed the problem by changing the value for RELAY_LOG_FILE
to be the basename of the log file as that for MASTER_LOG_FILE.
The problem is that there is only one autoinc value associated with
the query when binlogging. If more than one autoinc values are used
in the query, the autoinc values after the first one can be inserted
wrongly on slave. So these autoinc values can become inconsistent on
master and slave.
The problem is resolved by marking all the statements that invoke
a trigger or call a function that updated autoinc fields as unsafe,
and will switch to row-format in Mixed mode. Actually, the statement
is safe if just one autoinc value is used in sub-statement, but it's
impossible to check how many autoinc values are used in sub-statement.)
rpl_slave_skip fails randomly on PB2. This patch fixes the failure by
setting explicit wait for SQL thread to stop, instead of the
wait_for_slave_to_stop mysqltest command, after a start until command
is executed.
NOTE: Backporting the patch to next-mr.
The fix proposed in BUG#35542 and BUG#31665 introduces a performance issue
when fsyncing the master.info, relay.info and relay-log.bin* after #th events.
Although such solution has been proposed to reduce the probability of corrupted
files due to a slave-crash, the performance penalty introduced by it has
made the approach impractical for highly intensive workloads.
In a nutshell, the option --syn-relay-log proposed in BUG#35542 and BUG#31665
simultaneously fsyncs master.info, relay-log.info and relay-log.bin* and
this is the main source of performance issues.
This patch introduces new options that give more control to the user on
what should be fsynced and how often:
1) (--sync-master-info, integer) which syncs the master.info after #th event;
2) (--sync-relay-log, integer) which syncs the relay-log.bin* after #th
events.
3) (--sync-relay-log-info, integer) which syncs the relay.info after #th
transactions.
To provide both performance and increased reliability, we recommend the following
setup:
1) --sync-master-info = 0 eventually the operating system will fsync it;
2) --sync-relay-log = 0 eventually the operating system will fsync it;
3) --sync-relay-log-info = 1 fsyncs it after every transaction;
Notice, that the previous setup does not reduce the probability of
corrupted master.info and relay-log.bin*. To overcome the issue, this patch also
introduces a recovery mechanism that right after restart throws away relay-log.bin*
retrieved from a master and updates the master.info based on the relay.info:
4) (--relay-log-recovery, boolean) which enables a recovery mechanism that
throws away relay-log.bin* after a crash.
However, it can only recover the incorrect binlog file and position in master.info,
if other informations (host, port password, etc) are corrupted or incorrect,
then this recovery mechanism will fail to work.
vs not null
NOTE: Backporting the patch to next-mr.
The replication was generating corrupted data, warning messages on Valgrind
and aborting on debug mode while replicating a "null" to "not null" field.
Specifically the unpack_row routine, was considering the slave's table
definition and trying to retrieve a field value, where there was nothing to be
retrieved, ignoring the fact that the value was defined as "null" by the master.
To fix the problem, we proceed as follows:
1 - If it is not STRICT sql_mode, implicit default values are used, regardless
if it is multi-row or single-row statement.
2 - However, if it is STRICT mode, then a we do what follows:
2.1 If it is a transactional engine, we do a rollback on the first NULL that is
to be set into a NOT NULL column and return an error.
2.2 If it is a non-transactional engine and it is the first row to be inserted
with multi-row, we also return the error. Otherwise, we proceed with the
execution, use implicit default values and print out warning messages.
Unfortunately, the current patch cannot mimic the behavior showed by the master
for updates on multi-tables and multi-row inserts. This happens because such
statements are unfolded in different row events. For instance, considering the
following updates and strict mode:
(master)
create table t1 (a int);
create table t2 (a int not null);
insert into t1 values (1);
insert into t2 values (2);
update t1, t2 SET t1.a=10, t2.a=NULL;
t1 would have (10) and t2 would have (0) as this would be handled as a
multi-row update. On the other hand, if we had the following updates:
(master)
create table t1 (a int);
create table t2 (a int);
(slave)
create table t1 (a int);
create table t2 (a int not null);
(master)
insert into t1 values (1);
insert into t2 values (2);
update t1, t2 SET t1.a=10, t2.a=NULL;
On the master t1 would have (10) and t2 would have (NULL). On
the slave, t1 would have (10) but the update on t1 would fail.
NOTE: this is the backport to next-mr.
This patch addresses the bug reported by checking wether
host argument is an empty string or not. If empty, an error is
reported to the client, otherwise continue normally.
This commit is based on the originally proposed patch and adds
a test case as requested during review as well as refines comments,
and makes test case result file less verbose (compared to previous patch).
NOTE: this is the backport to next-mr.
When using replication, the slave will not log any slow query logs queries
replicated from the master, even if the option "--log-slow-slave-statements"
is set and these take more than "log_query_time" to execute.
In order to log slow queries in replicated thread one needs to set the
--log-slow-slave-statements, so that the SQL thread is initialized with the
correct switch. Although setting this flag correctly configures the slave
thread option to log slow queries, there is an issue with the condition that
is used to check whether to log the slow query or not. When replaying binlog
events the statement contains the SET TIMESTAMP clause which will force the
slow logging condition check to fail. Consequently, the slow query logging will
not take place.
This patch addresses this issue by removing the second condition from the
log_slow_statements as it prevents slow queries to be binlogged and seems
to be deprecated.
files
NOTE: this is the backport to next-mr.
SHOW BINLOG EVENTS does not work with relay log files. If issuing
"SHOW BINLOG EVENTS IN 'relay-log.000001'" in a non-empty relay
log file (relay-log.000001), mysql reports empty set.
This patch addresses this issue by extending the SHOW command
with RELAYLOG. Events in relay log files can now be inspected by
issuing SHOW RELAYLOG EVENTS [IN 'log_name'] [FROM pos] [LIMIT
[offset,] row_count].
"load data" statements were written to the binlog as a mix of the original statement
and bits recreated from parse-info. This relied on implementation details and broke
with IGNORE_SPACES and versioned comments.
We now completely resynthesize the query for LOAD DATA for binlog (which among other
things normalizes them somewhat with regard to case, spaces, etc.).
We have already parsed the query properly, so we make use of that rather
than mix-and-match string literals and parsed items.
This should make us safe with regard to versioned comments, even those
spanning multiple tokens. Also no longer affected by IGNORE_SPACES.
All statements executed by mysql_upgrade are binlogged and then are replicated to slave.
This will result in some errors. The report of this bug has demonstrated some examples.
Master and slave should be upgraded separately. All statements executed by
mysql_upgrade will not be binlogged.
--write-binlog and --skip-write-binlog options are added into mysql_upgrade.
These options control whether sql statements are binlogged or not.
HA_ERR_WRONG_INDEX
In RBR, disabling keys on slave table will break replication when
updating or deleting a record. When the slave thread tries to
find the row, by searching in the storage engine, it checks
whether the table has a key or not. If it has one, then the slave
thread uses it to search the record.
Nonetheless, the slave only checks whether the key exists or not,
it does not verify if it is active. Should the key be
disabled (eg, DBA has issued an ALTER TABLE ... DISABLE KEYS)
then it will result in error: HA_ERR_WRONG_INDEX.
This patch addresses this issue by making the slave thread also
check whether the key is active or not before actually using it.
But there is no Last_IO_Error reported.
On the master, if a binary log event is larger than max_allowed_packet,
ER_MASTER_FATAL_ERROR_READING_BINLOG and the specific reason of this error is
sent to a slave when it requests a dump from the master, thus leading
the I/O thread to stop.
On a slave, the I/O thread stops when receiving a packet larger than max_allowed_packet.
In both cases, however, there was no Last_IO_Error reported.
This patch adds code to report the Last_IO_Error and exact reason before stopping the
I/O thread and also reports the case the out memory pops up while
handling packets from the master.
The test case rpl_do_grant fails sporadically on PB2 with "Access
denied for user 'create_rout_db'@'localhost' ...". Inspecting the
test case, one may find that if issues a GRANT on the master
connection and immediately after it creates two new connections
(one to the master and one to the slave) using the credentials
set with the GRANT.
Unfortunately, there is no synchronization between master and
slave after the grant and before the connections are
established. This can result in slave not having executed the
GRANT by the time the connection is attempted.
This patch fixes this by deploying a sync_slave_with_master
between the grant and the connections attempt.
The test case creates two temporary tables, then closes the
connection, waits for it to disconnect, then syncs the slave with
the master, checks for remaining opened temporary tables on
slave (which should be 0) and finally drops the used
database (mysqltest).
Unfortunately, sometimes, the test fails with one open table on
the slave. This seems to be caused by the fact that waiting for
the connection to be closed is not sufficient. The test needs to
wait for the DROP event to be logged and only then synchronize
the slave with the master and proceed with the check. This is
caused by the asynchronous nature of the disconnect wrt
binlogging of the DROP temporary table statement.
We fix this by deploying a call to wait_for_binlog_event.inc
on the test case, which makes execution to wait for the DROP
temp tables event before synchronizing master and slave.
If an EVENT is created without the DEFINER clause set explicitly or with it set
to CURRENT_USER, the master and slaves become inconsistent. This issue stems from
the fact that in both cases, the DEFINER is set to the CURRENT_USER of the current
thread. On the master, the CURRENT_USER is the mysqld's user, while on the slave,
the CURRENT_USER is empty for the SQL Thread which is responsible for executing
the statement.
To fix the problem, we do what follows. If the definer is not set explicitly,
a DEFINER clause is added when writing the query into binlog; if 'CURRENT_USER' is
used as the DEFINER, it is replaced with the value of the current user before
writing to binlog.
binlog
Mixing transactional (T) and non-transactional (N) tables on behalf of a
transaction may lead to inconsistencies among masters and slaves in STATEMENT
mode. The problem stems from the fact that although modifications done to
non-transactional tables on behalf of a transaction become immediately visible
to other connections they do not immediately get to the binary log and therefore
consistency is broken. Although there may be issues in mixing T and M tables in
STATEMENT mode, there are safe combinations that clients find useful.
In this bug, we fix the following issue. Mixing N and T tables in multi-level
(e.g. a statement that fires a trigger) or multi-table table statements (e.g.
update t1, t2...) were not handled correctly. In such cases, it was not possible
to distinguish when a T table was updated if the sequence of changes was N and T.
In a nutshell, just the flag "modified_non_trans_table" was not enough to reflect
that both a N and T tables were changed. To circumvent this issue, we check if an
engine is registered in the handler's list and changed something which means that
a T table was modified.
Check WL 2687 for a full-fledged patch that will make the use of either the MIXED or
ROW modes completely safe.
In STATEMENT based replication, a statement that failed on the master but that
updated non-transactional tables is written to binary log with the error code
appended to it. On the slave, the statement is executed and the same error is
expected. However, when an "expected error" did not happen on the slave and was
either ignored or was related to a concurrency issue on the master, the slave
did not rollback the effects of the statement and as such inconsistencies might
happen.
To fix the problem, we automatically rollback a statement that should have
failed on a slave but succeded and whose expected failure is either ignored or
stems from a concurrency issue on the master.
