There were several cases where the slave GTID position was not loaded
correctly before being used. This caused various failures such as
corrupting the position at slave start and empty values of
@@gtid_slave_pos and @@gtid_current_pos.
Fixed by adding more checks for loaded position, and by always loading
the position at server startup.
Change of user interface to be more logical and more in line with expectations
to work similar to old-style replication.
User can now explicitly choose in CHANGE MASTER whether binlog position is
taken into account (master_gtid_pos=current_pos) or not (master_gtid_pos=
slave_pos) when slave connects to master.
@@gtid_pos is replaced by three separate variables @@gtid_slave_pos (can
be set by user, replicated GTIDs only), @@gtid_binlog_pos (read only), and
@@gtid_current_pos (a combination of the two, most recent GTID within each
domain). mysql.rpl_slave_state is renamed to mysql.gtid_slave_pos to match.
This fixes MDEV-4474.
The slave dump thread running on the master only checked thd->killed whenever
it reached the end of a binlog file, not between events. This could
unnecessarily delay server shutdown.
This was found by code inspection while tracking down some occasional "forcing
close of thread..." errors in Buildbot. Hopefully this will fix the failures,
but the fix is correct in any case.
Also increase the wait during server shutdown, 2 seconds is a bit tight in
case of heavy I/O stall, and it seems better to delay shutdown a bit than
force-kill threads unnecessarily.
Also fix some races in test cases that restart the mysqld server. The .expect
file should be changed with --append_file, --remove_file + --write_file
creates a short window where mysqld can error out due to .expect file missing.
Replace CHANGE MASTER TO ... master_gtid_pos='xxx' with a new system
variable @@global.gtid_pos.
This is more logical; @@gtid_pos is global, not per-master, and it is not
affected by RESET SLAVE.
Also rename master_gtid_pos=AUTO to master_use_gtid=1, which again is more
logical.
Implement test case rpl_gtid_stop_start.test to test normal stop and restart
of master and slave mysqld servers.
Fix a couple bugs found with the test:
- When InnoDB is disabled (no XA), the binlog state was not read when master
mysqld starts.
- Remove old code that puts a bogus D-S-0 into the initial binlog state, it
is not correct in current design.
- Fix memory leak in gtid_find_binlog_file().
