| Bug #56516 | Optimizing MERGE table asserts in MDL_context::upgrade_shared_lock_to_exclusive | ||
|---|---|---|---|
| Submitted: | 2 Sep 2010 19:03 | Modified: | 22 Sep 2010 8:22 |
| Reporter: | Matthias Leich | Email Updates: | |
| Status: | Duplicate | Impact on me: | |
| Category: | MySQL Server: Locking | Severity: | S3 (Non-critical) |
| Version: | 5.5.6, 5.5.7-bzr | OS: | Any |
| Assigned to: | Assigned Account | CPU Architecture: | Any |
| Tags: | locking, mdl, regression | ||
[2 Sep 2010 19:36]
Valeriy Kravchuk
Verified with current mysql-5.5 from bzr: macbook-pro:5.5 openxs$ bin/mysql -uroot test Reading table information for completion of table and column names You can turn off this feature to get a quicker startup with -A Welcome to the MySQL monitor. Commands end with ; or \g. Your MySQL connection id is 1 Server version: 5.5.7-m3-debug Source distribution Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved. This software comes with ABSOLUTELY NO WARRANTY. This is free software, and you are welcome to modify and redistribute it under the GPL v2 license Type 'help;' or '\h' for help. Type '\c' to clear the current input statement. mysql> CREATE TABLE t1 ( pk int, primary key (pk)); ERROR 1050 (42S01): Table 't1' already exists mysql> ALTER TABLE t1 ENGINE = MERGE UNION ( t_not_exists ); Query OK, 0 rows affected (0.08 sec) Records: 0 Duplicates: 0 Warnings: 0 mysql> OPTIMIZE TABLE t1; ERROR 2013 (HY000): Lost connection to MySQL server during query mysql> mysql> 100902 22:33:26 mysqld_safe mysqld restarted mysql> exit Bye macbook-pro:5.5 openxs$ tail -100 var/macbook-pro.err ... 100902 22:33:22 [Note] /Users/openxs/dbs/5.5/libexec/mysqld: ready for connections. Version: '5.5.7-m3-debug' socket: '/tmp/mysql.sock' port: 3306 Source distribution 100902 22:33:26 - mysqld got signal 10 ; 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=1 connection_count=1 It is possible that mysqld could use up to key_buffer_size + (read_buffer_size + sort_buffer_size)*max_threads = 337860 K bytes of memory Hope that's ok; if not, decrease some variables in the equation. thd: 0x1020000 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 = 0xb0576f34 thread_stack 0x30000 0 mysqld 0x005c2b79 my_print_stacktrace + 44 1 mysqld 0x00105c28 handle_segfault + 876 2 libSystem.B.dylib 0x940472bb _sigtramp + 43 3 ??? 0xffffffff 0x0 + 4294967295 4 mysqld 0x0016c822 _Z24wait_while_table_is_usedP3THDP5TABLE17ha_extra_function + 182 5 mysqld 0x001d9cfb _Z18mysql_print_statusv + 4397 6 mysqld 0x001db4ad _ZN24Optimize_table_statement7executeEP3THD + 321 7 mysqld 0x00120da9 _Z21mysql_execute_commandP3THD + 33113 8 mysqld 0x00121414 _Z11mysql_parseP3THDPcjP12Parser_state + 624 9 mysqld 0x00121fa6 _Z16dispatch_command19enum_server_commandP3THDPcj + 2632 10 mysqld 0x001233af _Z10do_commandP3THD + 621 11 mysqld 0x00110c21 _Z24do_handle_one_connectionP3THD + 425 12 mysqld 0x00110ce5 handle_one_connection + 37 13 libSystem.B.dylib 0x9400c095 _pthread_start + 321 14 libSystem.B.dylib 0x9400bf52 thread_start + 34 Trying to get some variables. Some pointers may be invalid and cause the dump to abort... thd->query at 0x109ca10 = OPTIMIZE TABLE t1 thd->thread_id=1 thd->killed=NOT_KILLED mysql-.5.1 does not crash, so this can be called a regression.
[6 Sep 2010 7:19]
Jon Olav Hauglid
A different manifestation of Bug#56494 and fixed by the proposed patch for Bug#56494.
[22 Sep 2010 8:22]
Jon Olav Hauglid
Closed as a duplicate of Bug#56494
Description: The crash happens in ../sql/mdl.cc:1941 : /* Do nothing if already upgraded. Used when we FLUSH TABLE under LOCK TABLES and a table is listed twice in LOCK TABLES list. */ ===> if (mdl_ticket->m_type == MDL_EXCLUSIVE) DBUG_RETURN(FALSE); My script: ========== --disable_warnings DROP TABLE IF EXISTS t1; DROP TABLE IF EXISTS t_not_exists; --enable_warnings CREATE TABLE t1 ( pk int, primary key (pk)); ALTER TABLE t1 ENGINE = MERGE UNION ( t_not_exists ); OPTIMIZE TABLE t1; DROP TABLE t1; Result on mysql-5.5-runtime revno: 3131 2010-09-01 The fix for the following bug which shows a similar backtrace is included Bug #54105 assert in MDL_context::release_locks_stored_before ================================================== TEST RESULT TIME (ms) --------------------------------------------- worker[1] Using MTR_BUILD_THREAD 300, with reserved ports 13000..13009 main.ml001 [ fail ] Test ended at 2010-09-02 20:19:11 ... CURRENT_TEST: main.ml001 mysqltest: At line 8: query 'OPTIMIZE TABLE t1' failed: 2013: Lost connection to MySQL server during query Thread 1 (process 31858): #0 0x00007f5b663cbce6 in pthread_kill () from /lib64/libpthread.so.0 #1 0x0000000000a0ffaf in my_write_core (sig=11) at ..../mysys/stacktrace.c:328 #2 0x0000000000547bcd in handle_segfault (sig=11) at ..../sql/mysqld.cc:2505 #3 <signal handler called> #4 0x00000000006b0436 in MDL_context::upgrade_shared_lock_to_exclusive (this=0x18824a0, mdl_ticket=0x0, lock_wait_timeout=31536000) at ..../sql/mdl.cc:1941 #5 0x000000000058c8a0 in wait_while_table_is_used (thd=0x18823e0, table=0x1943650, function=HA_EXTRA_PREPARE_FOR_RENAME) at ..../sql/sql_base.cc:2231 #6 0x00000000006b268e in mysql_admin_table (thd=0x18823e0, tables=0x1907100, check_opt=0x18849c8, operator_name=0xae69ea "optimize", lock_type=TL_WRITE, open_for_modify=true, no_warnings_for_error=false, extra_open_options=0, prepare_func=0, operator_func=0x728fa2 <handler::ha_optimize(THD*, st_ha_check_opt*)>, view_operator_func=0) at ..../sql/sql_admin.cc:491 #7 0x00000000006b3c41 in Optimize_table_statement::execute (this=0x1907610, thd=0x18823e0) at ..../sql/sql_admin.cc:955 #8 0x00000000005dbd46 in mysql_execute_command (thd=0x18823e0) at ..../sql/sql_parse.cc:4375 #9 0x00000000005dc2d4 in mysql_parse (thd=0x18823e0, rawbuf=0x1907030 "OPTIMIZE TABLE t1", length=17, parser_state=0x40479950) at ..../sql/sql_parse.cc:5554 #10 0x00000000005dce67 in dispatch_command (command=COM_QUERY, thd=0x18823e0, packet=0x193f641 "", packet_length=17) at ..../sql/sql_parse.cc:1099 #11 0x00000000005de255 in do_command (thd=0x18823e0) at ..../sql/sql_parse.cc:771 #12 0x00000000006a6365 in do_handle_one_connection (thd_arg=0x18823e0) at ..../sql/sql_connect.cc:1191 #13 0x00000000006a642a in handle_one_connection (arg=0x18823e0) at ..../sql/sql_connect.cc:1130 #14 0x000000000094e273 in pfs_spawn_thread (arg=0x18ec900) at ..../storage/perfschema/pfs.cc:1015 #15 0x00007f5b663c7040 in start_thread () from /lib64/libpthread.so.0 #16 0x00007f5b6548208d in clone () from /lib64/libc.so.6 #17 0x0000000000000000 in ?? () Result on mysql-5.1 revno: 3468 2010-08-19 ========================================== DROP TABLE IF EXISTS t1; DROP TABLE IF EXISTS t_not_exists; CREATE TABLE t1 ( pk int, primary key (pk)); ALTER TABLE t1 ENGINE = MERGE UNION ( t_not_exists ); OPTIMIZE TABLE t1; Table Op Msg_type Msg_text test.t1 optimize Error Table 'test.t_not_exists' doesn't exist test.t1 optimize Error Unable to open underlying table which is differently defined or of non-MyISAM type or doesn't exist test.t1 optimize error Corrupt DROP TABLE t1; How to repeat: See above