[#MDEV-8154] rpl.show_status_stop_slave_race-7126 sporadically causes internal check failure

I am also getting the failure (sporadically, but often enough) on a release build, but not on a debug build.

worker[1] Using MTR_BUILD_THREAD 300, with reserved ports 16000..16019

rpl.show_status_stop_slave_race-7126 'mix' [ pass ]   2121

MTR's internal check of the test case 'rpl.show_status_stop_slave_race-7126' failed.

This means that the test case does not preserve the state that existed

before the test case was executed.  Most likely the test case did not

do a proper clean-up. It could also be caused by the previous test run

by this thread, if the server wasn't restarted.

This is the diff of the states of the servers before and after the

test case was executed:

mysqltest: Logging to '/data/releases/mariadb-10.0.18-linux-x86_64/mysql-test/var/tmp/check-mysqld_2.log'.

mysqltest: Results saved in '/data/releases/mariadb-10.0.18-linux-x86_64/mysql-test/var/tmp/check-mysqld_2.result'.

mysqltest: Connecting to server localhost:16001 (socket /data/releases/mariadb-10.0.18-linux-x86_64/mysql-test/var/tmp/mysqld.2.sock) as 'root', connection 'default', attempt 0 ...

mysqltest: ... Connected.

mysqltest: Start processing test commands from './include/check-testcase.test' ...

mysqltest: ... Done processing test commands.

--- /data/releases/mariadb-10.0.18-linux-x86_64/mysql-test/var/tmp/check-mysqld_2.result	2015-05-13 02:02:04.000000000 +0300

+++ /data/releases/mariadb-10.0.18-linux-x86_64/mysql-test/var/tmp/check-mysqld_2.reject	2015-05-13 02:02:06.000000000 +0300

@@ -32,8 +32,8 @@

 Master_SSL_Key

 Seconds_Behind_Master	NULL

 Master_SSL_Verify_Server_Cert	No

-Last_IO_Errno	0

-Last_IO_Error

+Last_IO_Errno	2003

+Last_IO_Error	error connecting to master 'root@127.0.0.1:16000' - retry-time: 1  retries: 10  message: Can't connect to MySQL server on '127.0.0.1' (4 "Interrupted system call")

 Last_SQL_Errno	0

 Last_SQL_Error

 Replicate_Ignore_Server_Ids

mysqltest: Result length mismatch

The test runs "START SLAVE; STOP SLAVE" multiple times concurrently in two connections; so sometimes STOP from one connection interrupts starting from another connection, and the slave IO thread stops with the 'interrupted system call' error. If it happens to be the last state at the end of the concurrent flow, the test ends with this status because it doesn't have replication cleanup at the end.

The change below seems to fix the problem, but I need a confirmation that the "Interrupted system call" status is really allowed here.

diff --git a/mysql-test/suite/rpl/r/show_status_stop_slave_race-7126.result b/mysql-test/suite/rpl/r/show_status_stop_slave_race-7126.result

index e71bb2e..c2a0498 100644

--- a/mysql-test/suite/rpl/r/show_status_stop_slave_race-7126.result

+++ b/mysql-test/suite/rpl/r/show_status_stop_slave_race-7126.result

@@ -1,2 +1,4 @@

 include/master-slave.inc

 [connection master]

+start slave;

+include/rpl_end.inc

diff --git a/mysql-test/suite/rpl/t/show_status_stop_slave_race-7126.test b/mysql-test/suite/rpl/t/show_status_stop_slave_race-7126.test

index a79a188..38759c9 100644

--- a/mysql-test/suite/rpl/t/show_status_stop_slave_race-7126.test

+++ b/mysql-test/suite/rpl/t/show_status_stop_slave_race-7126.test

@@ -10,3 +10,10 @@

 --exec $MYSQL_SLAP --silent --socket=$SLAVE_MYSOCK -q "START SLAVE; STOP SLAVE; SHOW GLOBAL STATUS" -c 2 --number-of-queries=100 --create-s

 # All done.

+--connection slave

+start slave;

+--connection master

+--source include/rpl_end.inc

[MDEV-8154] rpl.show_status_stop_slave_race-7126 sporadically causes internal check failure Created: 2015-05-13 Updated: 2015-09-28 Resolved: 2015-05-13
Status:	Closed
Project:	MariaDB Server
Component/s:	Tests
Affects Version/s:	10.0
Fix Version/s:	5.5.46, 10.0.20

[MDEV-8154] rpl.show_status_stop_slave_race-7126 sporadically causes internal check failure Created: 2015-05-13 Updated: 2015-09-28 Resolved: 2015-05-13