mysql-community-mroonga with wrapper-mode table crashes when mysqld gotes to shutdown

[yoku0825]

mysql-community-mroonga and percona-server-56-mroonga crashes when I tried to stop mysqld.

• Using wrapper-mode table(wrapping InnoDB or MyISAM, both cases are affected)
• mysqld has table-cache wrapper-mode table.
  • I executed "FLUSH TABLES" before stopping mysqld and I would succeed shutdown mysqld.
  • Without any operation about wrapper-table, I would succeed shutdown mysqld.
• service mysqld stop and mysqladmin shutdown are both affected.

How to repeat

$ sudo yum install mysql-community-mroonga
$ sudo service mysqld start
$ mysql -uroot
mysql> CREATE DATABASE d1;
mysql> CREATE TABLE d1.t1 (num int PRIMARY KEY) Engine= Mroonga COMMENT 'Engine "InnoDB"';
mysql> INSERT INTO d1.t1 VALUES (1);
mysql> quit
$ sudo service mysqld stop

MySQL error-log

2015-08-07 18:07:02 1155 [Note] /usr/sbin/mysqld: Normal shutdown

2015-08-07 18:07:02 1155 [Note] Giving 0 client threads a chance to die gracefully
2015-08-07 18:07:02 1155 [Note] Event Scheduler: Purging the queue. 0 events
2015-08-07 18:07:02 1155 [Note] Shutting down slave threads
2015-08-07 18:07:02 1155 [Note] Forcefully disconnecting 0 remaining clients
2015-08-07 18:07:02 1155 [Note] Binlog end
09:07:02 UTC - mysqld got signal 11 ;
This could be because you hit a bug. It is also possible that this binary
or one of the libraries it was linked against is corrupt, improperly built,
or misconfigured. This error can also be caused by malfunctioning hardware.
We will try our best to scrape up some info that will hopefully help
diagnose the problem, but since we have already crashed,
something is definitely wrong and this may fail.

key_buffer_size=8388608
read_buffer_size=131072
max_used_connections=1
max_threads=151
thread_count=0
connection_count=0
It is possible that mysqld could use up to
key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 68108 K  bytes of memory
Hope that's ok; if not, decrease some variables in the equation.

Thread pointer: 0x0
Attempting backtrace. You can use the following information to find out
where mysqld died. If you see no messages after this, something went
terribly wrong...
stack_bottom = 0 thread_stack 0x40000
/usr/sbin/mysqld(my_print_stacktrace+0x35)[0x8dc435]
/usr/sbin/mysqld(handle_fatal_signal+0x494)[0x665254]
/lib64/libpthread.so.0(+0xf710)[0x7fce2e0e8710]
/usr/lib64/mysql/plugin/ha_mroonga.so(mrn_get_slot_data+0x2a)[0x7fce12bec59a]
/usr/lib64/mysql/plugin/ha_mroonga.so(_ZN10ha_mroonga13add_wrap_htonEPKcP10handlerton+0x30)[0x7fce12bd7f40]
/usr/lib64/mysql/plugin/ha_mroonga.so(_ZN10ha_mroonga5closeEv+0x89)[0x7fce12bdc539]
/usr/sbin/mysqld(_Z8closefrmP5TABLEb+0xf9)[0x76f659]
/usr/sbin/mysqld(_Z18intern_close_tableP5TABLE+0x36)[0x6946e6]
/usr/sbin/mysqld(_ZN11Table_cache22free_all_unused_tablesEv+0x8a)[0x7780da]
/usr/sbin/mysqld(_ZN19Table_cache_manager22free_all_unused_tablesEv+0x44)[0x7781f4]
/usr/sbin/mysqld(_Z19close_cached_tablesP3THDP10TABLE_LISTbm+0x6f3)[0x6a0603]
/usr/sbin/mysqld[0x59afa3]
/usr/sbin/mysqld(_Z10unireg_endv+0xe)[0x59b34e]
/usr/sbin/mysqld[0x59e688]
/usr/sbin/mysqld(kill_server_thread+0xe)[0x59e88e]
/usr/sbin/mysqld(pfs_spawn_thread+0x12a)[0x96192a]
/lib64/libpthread.so.0(+0x79d1)[0x7fce2e0e09d1]
/lib64/libc.so.6(clone+0x6d)[0x7fce2ce498fd]
The manual page at http://dev.mysql.com/doc/mysql/en/crashing.html contains
information that should help you find out what is causing the crash.
150807 18:07:02 mysqld_safe Number of processes running now: 0

groonga.log

• Nothing about issue.

2015-08-07 18:06:50.009285|n|2e507720|mroonga 5.05 started.
2015-08-07 18:06:50.009366|n|2e507720|log level is 'NOTICE'
2015-08-07 18:07:03.550970|n|8caa8720|mroonga 5.05 started.
2015-08-07 18:07:03.551080|n|8caa8720|log level is 'NOTICE'

[kou]

Thanks for your report. I've fixed it.

It's a bug that was introduced for supporting MariaDB 10.1. Mroonga 5.04 and 5.05 have this bug.

[yoku0825]

I confirmed your fix works well in our production environment!
Thank you for your quick fix!! 👍