mysql> use test;

mysql> set session autocommit=false;

mysql> begin;

mysql> insert into t2 values (9);

mysql> insert into t2 values (9);

[root@vqc007c ~]# mysql -h karma197 -P 6008 -u maxscale -pmaxscale_pw

mysql: [Warning] Using a password on the command line interface can be insecure.

Welcome to the MySQL monitor.  Commands end with ; or \g.

Your MySQL connection id is 10

Server version: 5.0.45-clustrix-fredonyer-16045

Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its

affiliates. Other names may be trademarks of their respective

owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> set session autocommit=false;

Query OK, 0 rows affected (0.01 sec)

mysql> use test;

Reading table information for completion of table and column names

You can turn off this feature to get a quicker startup with -A

Database changed

mysql> begin;

Query OK, 0 rows affected (0.00 sec)

mysql> insert into t1 values (19);

Query OK, 1 row affected (0.00 sec)

mysql> insert into t1 values (20);

ERROR 1927 (08S01): Transaction checksum mismatch encountered when replaying transaction.

mysql>

2019-08-22 22:22:27   info   : (10) [readwritesplit] Reply complete, last reply from @@Clustrix:node-1

2019-08-22 22:22:27   info   : (10) [readwritesplit] Replaying: insert into t1 values (19)

2019-08-22 22:22:27   info   : > Autocommit: [disabled], trx is [open], cmd: (0x03) COM_QUERY, plen: 31, type: QUERY_TYPE_WRITE, stmt: insert into t1 values (19)

2019-08-22 22:22:27   info   : [readwritesplit] Route query to master: @@Clustrix:node-1        [10.2.13.91]:3306 <

2019-08-22 22:22:27   info   : (10) [readwritesplit] Adding to trx: insert into t1 values (19)

2019-08-22 22:22:27   info   : (10) [readwritesplit] Reply complete, last reply from @@Clustrix:node-1

2019-08-22 22:22:27   info   : (10) [readwritesplit] Checksum mismatch, transaction replay failed. Closing connection.

2019-08-22 22:22:27   info   : Stopped RCR client session [10]

2019-08-22 22:22:28   notice : Server changed state: Bootstrap1-karma108[10.2.13.91:3306]: master_up. [Down] -> [Master, Running]

[root@karma197 log]# cat /etc/clustrix_karma108_trxreplay.cnf

[maxscale]

log_info=1

threads=auto

logdir=/data/clustrix/log

[Bootstrap1-karma108]

type=server

address=10.2.13.91

port=3306

protocol=mariadbbackend

#karma108

[Clustrix]

type=monitor

module=clustrixmon

servers=Bootstrap1-karma108

user=maxscale

password=maxscale_pw

cluster_monitor_interval=10000

[RCR]

type=service

router=readwritesplit

user=maxscale

password=maxscale_pw

cluster=Clustrix

transaction_replay=true

slave_selection_criteria=LEAST_GLOBAL_CONNECTIONS

delayed_retry_timeout=360s

transaction_replay_attempts=500

[RCR-Listener]

type=listener

service=RCR

protocol=MariaDBClient

port=6008

[MaxAdmin-Service]

type=service

router=cli

[MaxAdmin-Unix-Listener]

type=listener

service=MaxAdmin-Service

protocol=maxscaled

socket=default

mysql> use test;

mysql> set session autocommit=false;

mysql> insert into t2 values (9);

$ sudo clx dbrestart

mysql> insert into t2 values (9);

mysql> commit;

mysql> use test;

mysql> set session autocommit=false;

mysql> insert into t2 values (9);

$ sudo clx dbrestart

mysql> insert into t2 values (9);

^CCtrl-C -- query killed. Continuing normally.

^CCtrl-C -- query killed. Continuing normally.

^CCtrl-C -- exit!

Aborted

commit 8bc4e42f2df62deed6b34d40299112690cf20753

Author: Markus Mäkelä <markus.makela@mariadb.com>

Date:   Tue Aug 6 11:17:15 2019 +0300

    Fix query queuing on session command execution

    If session command execution during server reconnection caused a query to

    be queued, the query would be put on the tail end of the queue. This would

    cause queries to be reordered if the queue wasn't empty. The correct thing

    to do would be to put the next pending query back at the front of the

    queue.

diff --git a/server/modules/routing/readwritesplit/rwsplit_route_stmt.cc b/server/modules/routing/readwritesplit/rwsplit_route_stmt.cc

index 28b4d11b8..7919d5a0a 100644

--- a/server/modules/routing/readwritesplit/rwsplit_route_stmt.cc

+++ b/server/modules/routing/readwritesplit/rwsplit_route_stmt.cc

@@ -336,7 +336,7 @@ bool RWSplitSession::route_single_stmt(GWBUF* querybuf)

             else if (target->has_session_commands())

             {

                 // We need to wait until the session commands are executed

-                m_query_queue.emplace_back(gwbuf_clone(querybuf));

+                m_query_queue.emplace_front(gwbuf_clone(querybuf));

                 MXS_INFO("Queuing query until '%s' completes session command", target->name());

             }

             else

Case 1:

[root@vqc007c ~]# mysql -h karma182 -P 6008 -u maxscale -pmaxscale_pw

mysql: [Warning] Using a password on the command line interface can be insecure.

Welcome to the MySQL monitor.  Commands end with ; or \g.

Your MySQL connection id is 1

Server version: 5.5.5-10.2.12 2.4.2-maxscale

Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its

affiliates. Other names may be trademarks of their respective

owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> set session autocommit=false;

Query OK, 0 rows affected (0.01 sec)

mysql> use test;

Reading table information for completion of table and column names

You can turn off this feature to get a quicker startup with -A

Database changed

mysql> begin;

Query OK, 0 rows affected (0.00 sec)

mysql> insert into t1 values (2);

Query OK, 1 row affected (0.01 sec)

Restarted the cluster and run following before it can form group

mysql> insert into t1 values (3);

ERROR 1927 (08S01): Transaction checksum mismatch encountered when replaying transaction.

Case 2:

[root@vqc007c ~]# mysql -h karma182 -P 6008 -u maxscale -pmaxscale_pw

mysql: [Warning] Using a password on the command line interface can be insecure.

Welcome to the MySQL monitor.  Commands end with ; or \g.

Your MySQL connection id is 1

Server version: 5.5.5-10.2.12 2.4.2-maxscale

Copyright (c) 2000, 2016, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its

affiliates. Other names may be trademarks of their respective

owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> set session autocommit=false;

Query OK, 0 rows affected (0.01 sec)

mysql> use test;

Reading table information for completion of table and column names

You can turn off this feature to get a quicker startup with -A

Database changed

mysql> begin;

Query OK, 0 rows affected (0.00 sec)

mysql> insert into t1 values (4);

Query OK, 1 row affected (0.00 sec)

Restarted the cluster and run following after group is formed.

mysql> insert into t1 values (5);

ERROR 1927 (08S01): Transaction checksum mismatch encountered when replaying transaction.

mysql>