# MDEV-20821 parallel slave server shutdown hang
#
# Test the bug condition of a parallel slave server shutdown
# hang when the parallel workers were idle.
# The bug reported scenario is extented to cover the multi-sources case as well as
# checking is done for both the idle and busy workers cases.
# 
# MDEV-25336 Parallel replication causes failed assert while restarting
#   Since this test case involves slave restart this will help in testing
#   Mdev-25336 too.

--source include/have_innodb.inc
--source include/have_binlog_format_mixed.inc
--let $rpl_topology= 1->3
--source include/rpl_init.inc

#
# A. idle workers.
#
--connection server_3
set default_master_connection = '';
--source include/start_slave.inc

set default_master_connection = 'm2';
--replace_result $SERVER_MYPORT_2 SERVER_MYPORT_2
eval change master to master_host='127.0.0.1', master_port=$SERVER_MYPORT_2, master_user='root', master_use_gtid=slave_pos;
--source include/start_slave.inc

select @@global.slave_parallel_workers as two;

# At this point worker threads have no assignement.
# Shutdown must not hang.
# In 10.2/10.3 there should not be any assert failure `prev != 0 && next != 0'
--connection server_3
--write_file $MYSQLTEST_VARDIR/tmp/mysqld.3.expect
wait
EOF
--send SHUTDOWN
--reap
--source include/wait_until_disconnected.inc

--connection server_3
--append_file $MYSQLTEST_VARDIR/tmp/mysqld.3.expect
restart
EOF

# No hang is *proved* to occur when this point is reached.
--connection server_3
--enable_reconnect
--source include/wait_until_connected_again.inc

#
# B. resting workers after some busy time
#
--connection server_1
create table t1 (i int primary key) engine=Innodb;

--connection server_2
create table t2 (i int primary key) engine=Innodb;

--connection server_3
set default_master_connection = '';
--source include/start_slave.inc

set default_master_connection = 'm2';
--source include/start_slave.inc

--connection server_2
insert into t2 values (1);
--save_master_pos

--connection server_3
--sync_with_master 0,'m2'

--connection server_1
insert into t1 values (1);
--save_master_pos

--connection server_3
--sync_with_master 0,''

# In 10.2/10.3 there should not be any assert failure `prev != 0 && next != 0'
# At this point worker threads have no assignement.
# Shutdown must not hang.

--connection server_3
--write_file $MYSQLTEST_VARDIR/tmp/mysqld.3.expect
wait
EOF
--send SHUTDOWN
--reap
--source include/wait_until_disconnected.inc

--connection server_3
--append_file $MYSQLTEST_VARDIR/tmp/mysqld.3.expect
restart
EOF

# No hang is *proved* to occur when this point is reached.
--connection server_3
--enable_reconnect
--source include/wait_until_connected_again.inc

#
# C. busy workers
#
--connection server_3
set default_master_connection = '';
--source include/start_slave.inc

set default_master_connection = 'm2';
--source include/start_slave.inc

--connect (conn_block_server3, 127.0.0.1, root,, test, $SERVER_MYPORT_3,)
begin;
  insert into t1 values (2);
  insert into t2 values (2);

--connection server_1
insert into t1 values (2);
--connection server_2
insert into t2 values (2);


# In 10.2/10.3 there should not be any assert failure `prev != 0 && next != 0'
# At this point there's a good chance the worker threads are busy.
# SHUTDOWN must proceed without any delay as above.
--connection server_3
--write_file $MYSQLTEST_VARDIR/tmp/mysqld.3.expect
wait
EOF
--send SHUTDOWN
--reap
--source include/wait_until_disconnected.inc

--connection server_3
--append_file $MYSQLTEST_VARDIR/tmp/mysqld.3.expect
restart
EOF

# No hang is *proved* to occur when this point is reached.
--connection server_3
--enable_reconnect
--source include/wait_until_connected_again.inc


# Cleanup

--connection server_3
set default_master_connection = '';
--source include/start_slave.inc

set default_master_connection = 'm2';
--source include/start_slave.inc

--connection server_1
drop table t1;

--connection server_2
drop table t2;
--save_master_pos

# (!) The following block is critical to avoid check-mysqld_3.reject by mtr:
--connection server_3
--sync_with_master 0,'m2'
set default_master_connection = 'm2';
--source include/stop_slave.inc
RESET SLAVE ALL;
set default_master_connection = '';

--source include/rpl_end.inc