This commit makes replicas crash-safe by default by changing the
Using_Gtid value to be Slave_Pos on a fresh slave start and after
RESET SLAVE is issued. If the primary server does not support GTIDs
(i.e., version < 10), the replica will fall back to Using_Gtid=No on
slave start and after RESET SLAVE.
The following additional informational messages/warnings are added:
1. When Using_Gtid is automatically changed. That is, if RESET
SLAVE reverts Using_Gtid back to Slave_Pos, or Using_Gtid is
inferred to No from a CHANGE MASTER TO given with log coordinates
without MASTER_USE_GTID.
2. If options are ignored in CHANGE MASTER TO. If CHANGE MASTER TO
is given with log coordinates, yet also specifies
MASTER_USE_GTID=Slave_Pos, a warning message is given that the log
coordinate options are ignored.
Additionally, an MTR macro has been added for RESET SLAVE,
reset_slave.inc, which provides modes/options for resetting a slave
in log coordinate or gtid modes. When in log coordinates mode, the
macro will execute CHANGE MASTER TO MASTER_USE_GTID=No after the
RESET SLAVE command. When in GTID mode, an extra parameter,
reset_slave_keep_gtid_state, can be set to reset or preserve the
value of gtid_slave_pos.
Reviewed By:
===========
Andrei Elkin <andrei.elkin@mariadb.com>
The XtraDB storage engine was already replaced by InnoDB
and disabled in MariaDB Server 10.2. Let us remove it altogether
to avoid dragging dead code around.
Replace some references to XtraDB with references to InnoDB.
rpl_get_position_info(): Remove.
Remove the mysql-test-run --suite=percona, because it only contains
tests specific to XtraDB, many of which were disabled already in
earlier MariaDB versions.
The issue was that when running with valgrind the wait for master_pos_Wait()
was not long enough.
This patch also fixes two other failures that could affect rpl_mdev6020:
- check_if_conflicting_replication_locks() didn't properly check domains
- 'did_mark_start_commit' was after signals to other threads was sent which could
get the variable read too early.
replication causing replication to fail.
In parallel replication, we run transactions from the master in parallel, but
force them to commit in the same order they did on the master. If we force T1
to commit before T2, but T2 holds eg. a row lock that is needed by T1, we get
a deadlock when T2 waits until T1 has committed.
Usually, we do not run T1 and T2 in parallel if there is a chance that they
can have conflicting locks like this, but there are certain edge cases where
it can occasionally happen (eg. MDEV-5914, MDEV-5941, MDEV-6020). The bug was
that this would cause replication to hang, eventually getting a lock timeout
and causing the slave to stop with error.
With this patch, InnoDB will report back to the upper layer whenever a
transactions T1 is about to do a lock wait on T2. If T1 and T2 are parallel
replication transactions, and T2 needs to commit later than T1, we can thus
detect the deadlock; we then kill T2, setting a flag that causes it to catch
the kill and convert it to a deadlock error; this error will then cause T2 to
roll back and release its locks (so that T1 can commit), and later T2 will be
re-tried and eventually also committed.
The kill happens asynchroneously in a slave background thread; this is
necessary, as the reporting from InnoDB about lock waits happen deep inside
the locking code, at a point where it is not possible to directly call
THD::awake() due to mutexes held.
Deadlock is assumed to be (very) rarely occuring, so this patch tries to
minimise the performance impact on the normal case where no deadlocks occur,
rather than optimise the handling of the occasional deadlock.
Also fix transaction retry due to deadlock when it happens after a transaction
already signalled to later transactions that it started to commit. In this
case we need to undo this signalling (and later redo it when we commit again
during retry), so following transactions will not start too early.
Also add a missing thd->send_kill_message() that got triggered during testing
(this corrects an incorrect fix for MySQL Bug#58933).
