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--source include/have_innodb.inc
--source include/have_debug.inc
--source include/have_debug_sync.inc
--source include/have_binlog_format_mixed.inc
--source include/master-slave.inc
--connection slave
--source include/stop_slave.inc
SET @old_parallel_threads= @@GLOBAL.slave_parallel_threads;
SET GLOBAL slave_parallel_threads=3;
SET @old_parallel_mode= @@GLOBAL.slave_parallel_mode;
SET GLOBAL slave_parallel_mode=aggressive;
SET @old_dbug= @@GLOBAL.debug_dbug;
CHANGE MASTER TO master_use_gtid=slave_pos;
--source include/start_slave.inc
--echo *** MDEV-31509: Lost data with FTWRL and STOP SLAVE
# The bug was as follows:
# 1. Event groups T1 and T2 are queued but not started yet.
# 2. FLUSH TABLE WITH READ LOCKS starts, sets rpl_parallel_entry::pause_sub_id
# 3. T2 Sees pause_sub_id, goes to wait for the pause to complete.
# 4. FTWRL completes, UNLOCK TABLES is run.
# 5. STOP SLAVE is run, sets rpl_parallel_entry::stop_sub_id.
# 6. T2 wakes up after FTWRL pause, only now sets
# rpl_parallel_entry::largest_started_sub_id. This is the bug,
# largest_started_sub_id is set too late here.
# 7. T1 starts, it sees stop_sub_id<T1, so T1 is skipped due to STOP SLAVE.
# 8. T2 continues, its check for stop_sub_id was before STOP SLAVE. So T2 is
# wrongly applied, silently losing transaction T1.
--connection master
ALTER TABLE mysql.gtid_slave_pos ENGINE=InnoDB;
CREATE TABLE t1 (a INT PRIMARY KEY, b INT) ENGINE=InnoDB;
CREATE TABLE t2 (a INT PRIMARY KEY, b INT) ENGINE=MyISAM;
INSERT INTO t1 VALUES (0,0);
INSERT INTO t2 VALUES (0,0);
--source include/save_master_gtid.inc
--connection slave
--source include/sync_with_master_gtid.inc
--connection slave
--echo *** Arrange for T1 to delay before entering GCO wait.
SET GLOBAL debug_dbug="+d,gco_wait_delay_gtid_0_x_99";
--echo *** Arrange for T2 to wait for FTWRL to start.
SET GLOBAL debug_dbug="+d,hold_worker_on_schedule";
--echo *** Arrange for T2 to delay wakeup from FTWRL pause.
SET GLOBAL debug_dbug="+d,delay_ftwrl_wait_gtid_0_x_100";
--connection master
--echo *** Event group T1
SET SESSION gtid_seq_no=99;
INSERT INTO t1 VALUES (1,1);
--connection slave
--echo *** 1a. Wait for T1 to be queued.
SET debug_sync="now WAIT_FOR gco_wait_paused";
--connection master
--echo *** Event group T2
SET SESSION gtid_seq_no=100;
INSERT INTO t2 VALUES (2,2);
--connection slave
--echo *** 1b. Wait for T2 to be queued.
SET debug_sync= "now WAIT_FOR reached_pause";
--connection slave1
--echo *** 2. Run FTWRL
SET GLOBAL debug_dbug= "+d,pause_for_ftwrl_wait";
send FLUSH TABLES WITH READ LOCK;
--connection slave
SET debug_sync= "now WAIT_FOR pause_ftwrl_waiting";
--echo *** 3. Wait for T2 to be waiting for FTWRL pause
SET debug_sync= "now SIGNAL continue_worker";
--let $wait_condition= SELECT count(*) = 1 FROM information_schema.processlist WHERE state LIKE "%Waiting due to global read lock%" and command="Slave_worker";
--source include/wait_condition.inc
--echo *** 4. FTWRL completes, UNLOCK TABLES.
SET debug_sync="now SIGNAL pause_ftwrl_cont";
--connection slave1
reap;
UNLOCK TABLES;
--connection slave
--echo *** T2 is now ready to proceed after FTWRL pause, but did not wake up yet.
SET debug_sync="now WAIT_FOR pause_wait_started";
--echo *** 5. STOP SLAVE is run.
--connection slave1
SET GLOBAL debug_dbug="+d,rpl_parallel_wait_for_done_trigger";
send STOP SLAVE;
--connection slave
SET debug_sync="now WAIT_FOR wait_for_done_waiting";
--echo *** 5. T2 wakes up after FTWRL pause, reaches wait_for_prior_commit().
SET debug_sync="now SIGNAL pause_wait_continue";
--let $wait_condition= SELECT count(*) = 1 FROM information_schema.processlist WHERE state LIKE "%Waiting for prior transaction to commit%" and command="Slave_worker";
--source include/wait_condition.inc
--echo *** 6. T1 starts.
SET debug_sync="now SIGNAL gco_wait_cont";
--connection slave1
reap;
--connection slave
--source include/wait_for_slave_to_stop.inc
--connection master
SELECT * FROM t1 ORDER BY a;
SELECT * FROM t2 ORDER BY a;
--source include/save_master_gtid.inc
--connection slave
--source include/start_slave.inc
--source include/sync_with_master_gtid.inc
# The bug here was that T2 was errorneously replicated while T1 was
# being skipped due to STOP SLAVE. So the @@gtid_slave_pos was at T2,
# but we were missing the data from T1.
SELECT @@GLOBAL.gtid_slave_pos;
SELECT * FROM t1 ORDER BY a;
SELECT * FROM t2 ORDER BY a;
--echo *** Clean up.
--connection slave
--source include/stop_slave.inc
SET DEBUG_SYNC= "RESET";
SET GLOBAL slave_parallel_threads= @old_parallel_threads;
SET GLOBAL slave_parallel_mode= @old_parallel_mode;
SET GLOBAL debug_dbug=@old_dbug;
--source include/start_slave.inc
--connection master
DROP TABLE t1, t2;
--source include/rpl_end.inc
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