Enabling and disabling slow query log rotation spuriously adds version suffix to the next slow query log file name

[Laurynas Biveinis]

main.percona_bug643149 w4 [ fail ]
        Test ended at 2017-07-12 17:17:15

CURRENT_TEST: main.percona_bug643149
Unable to read slow query log file /mnt/workspace/percona-server-5.7-trunk/BUILD_TYPE/release/Host/ubuntu-zesty-32bit/build/mysql-test/var/4/percona_bug643149_slow.slog: No such file or directory
mysqltest: At line 13: command "perl" failed with error 2. my_errno=175

The result from queries just before the failure was:
SET LOCAL log_slow_verbosity='profiling';
SET LOCAL long_query_time=0;
[log_start.inc] percona_bug643149_slow
SELECT 1;
1
1
[log_stop.inc] percona_bug643149_slow
safe_process[10050]: Child process: 10051, exit: 1

Server [mysqld.1 - pid: 9439, winpid: 9439] log:
Server log from this test:
----------SERVER LOG START-----------
----------SERVER LOG END-------------

[Laurynas Biveinis (laurynas-biveinis)]

To reproduce, $ ./mtr --debug-server percona_bug1416582 percona_bug643149. It looks like percona_bug1416582 breaks it.

[Laurynas Biveinis (laurynas-biveinis)]

This is a 5.7 port code regression: setting max_slowlog_size to some value, resetting it to zero, and then setting the slow query log file name results in version suffix being appended where it should not be.

[Laurynas Biveinis (laurynas-biveinis)]

The following shows non-versioned percona_bug643149_slow.slog on 5.5/5.6, and versioned on 5.7

SET @old_max_slowlog_size = @@global.max_slowlog_size;
SET @old_slow_query_log_file = @@global.slow_query_log_file;
SET GLOBAL max_slowlog_size=10240000;

--replace_result $MYSQLTEST_VARDIR MYSQLTEST_VARDIR
eval SET GLOBAL slow_query_log_file='$MYSQLTEST_VARDIR/abcd';

SET @@global.max_slowlog_size = @old_max_slowlog_size;
SET @@global.slow_query_log_file = @old_slow_query_log_file;

--remove_files_wildcard $MYSQLTEST_VARDIR abcd*

--replace_result $MYSQLTEST_VARDIR MYSQLTEST_VARDIR
eval SET GLOBAL slow_query_log_file = '$MYSQLTEST_VARDIR/percona_bug643149_slow.slog';

SET GLOBAL slow_query_log_file = @old_slow_query_log_file;

list_files $MYSQLTEST_VARDIR percona_bug643149_slow*;

--remove_files_wildcard $MYSQLTEST_VARDIR *.slog

[Laurynas Biveinis (laurynas-biveinis)]

    https://github.com/percona/percona-server/pull/1827
    https://github.com/percona/percona-server/pull/1828
    https://github.com/percona/percona-server/pull/1829

[Shahriyar Rzayev (rzayev-sehriyar)]

Percona now uses JIRA for bug reports so this bug report is migrated to: https://jira.percona.com/browse/PS-1810