Bug #42147 Concurrent DML and LOCK TABLE ... READ for InnoDB
table cause warnings in errlog
Concurrent execution of LOCK TABLES ... READ statement and DML statements
affecting the same InnoDB table on debug builds of MySQL server might lead
to "Found lock of type 6 that is write and read locked" warnings appearing
in error log.
The problem is that the table-level locking code allows a thread to acquire
TL_READ_NO_INSERT lock on a table even if there is another thread which holds
TL_WRITE_ALLOW_WRITE lock on the same table. At the same time, the locking
code assumes that that such locks are incompatible (for example, see check_locks()).
This doesn't lead to any problems other than warnings in error log for
debug builds of server since for InnoDB tables TL_READ_NO_INSERT type of
lock is only used for LOCK TABLES and for this statement InnoDB also
performs its own table-level locking.
Unfortunately, the table lock compatibility matrix cannot be updated to disallow
TL_READ_NO_INSERT when another thread holds TL_WRITE_ALLOW_WRITE without
causing starvation of LOCK TABLE READ in InnoDB under high write load.
This patch therefore contains no code changes.
The issue will be fixed later when LOCK TABLE READ has been updated
to not use table locks. This bug will therefore be marked as
"To be fixed later".
Code comment in thr_lock.c expanded to clarify the issue and a
test case based on the bug description added to innodb_mysql_lock.test.
Note that a global suppression rule has been added to both MTR v1 and v2
for the "Found lock of type 6 that is write and read locked" warning.
These suppression rules must be removed once this bug is properly fixed.
Text conflict in mysql-test/collections/default.experimental
Text conflict in mysql-test/r/show_check.result
Text conflict in mysql-test/r/sp-code.result
Text conflict in mysql-test/suite/binlog/r/binlog_tmp_table.result
Text conflict in mysql-test/suite/rpl/t/disabled.def
Text conflict in mysql-test/t/show_check.test
Text conflict in mysys/my_delete.c
Text conflict in sql/item.h
Text conflict in sql/item_cmpfunc.h
Text conflict in sql/log.cc
Text conflict in sql/mysqld.cc
Text conflict in sql/repl_failsafe.cc
Text conflict in sql/slave.cc
Text conflict in sql/sql_parse.cc
Text conflict in sql/sql_table.cc
Text conflict in sql/sql_yacc.yy
Text conflict in storage/myisam/ha_myisam.cc
Corrected results for
stm_auto_increment_bug33029.reject 2009-12-01
20:01:49.000000000 +0300
<andrei> @@ -42,9 +42,6 @@
<andrei> RETURN i;
<andrei> END//
<andrei> CALL p1();
<andrei> -Warnings:
<andrei> -Note 1592 Statement may not be safe to log in statement
format.
<andrei> -Note 1592 Statement may not be safe to log in statement
format.
There should be indeed no Note present because there is in fact autoincrement
top-level query in sp() that triggers inserting in yet another auto-inc table.
(todo: alert DaoGang to improve the test).
applied revisions: r6185, r6186, r6189, r6194
r6185 - only code changes incorporated, changesets which change
innodb tests in the main mysql suite are discarded
r61889 - Fixes BUG#48782
Detailed revision comments:
r6185 | marko | 2009-11-17 16:44:20 +0200 (Tue, 17 Nov 2009) | 16 lines
branches/zip: Report duplicate table names
to the client connection, not to the error log. This change will allow
innodb-index.test to be re-enabled. It was previously disabled, because
mysql-test-run does not like output in the error log.
row_create_table_for_mysql(): Do not output anything to the error log
when reporting DB_DUPLICATE_KEY. Let the caller report the error.
Add a TODO comment that the dict_table_t object is apparently not freed
when an error occurs.
create_table_def(): Convert InnoDB table names to the character set
of the client connection for reporting. Use my_error(ER_WRONG_COLUMN_NAME)
for reporting reserved column names. Report my_error(ER_TABLE_EXISTS_ERROR)
when row_create_table_for_mysql() returns DB_DUPLICATE_KEY.
rb://206
r6186 | vasil | 2009-11-17 16:48:14 +0200 (Tue, 17 Nov 2009) | 4 lines
branches/zip:
Add ChangeLog entry for r6185.
r6189 | marko | 2009-11-18 11:36:18 +0200 (Wed, 18 Nov 2009) | 5 lines
branches/zip: ha_innobase::add_index(): When creating the primary key
and the table is being locked by another transaction,
do not attempt to drop the table. (Bug #48782)
Approved by Sunny Bains over IM
r6194 | vasil | 2009-11-19 09:24:45 +0200 (Thu, 19 Nov 2009) | 5 lines
branches/zip:
Increment version number from 1.0.5 to 1.0.6 since 1.0.5 was just released
by MySQL and we will soon release 1.0.6.
the 'shared-memory-base-name' was added to the [client] section of the my.cnf file.
That option isn't supported by the mysqltest_embedded.
per-file comments:
mysql-test/lib/My/ConfigFactory.pm
Post-push fix: Removed MTRv1 arguments according to the
original patch. Although there is a version check, the patch
was pushed to a 5.1 GA staging tree, while the version check
considers version 5.2. This makes the deprecated parameters
to be used, despite the fact that they are not valid anymore.
Part of MTRv1 is currently used in RQG semisync test, and this
was causing the test to fail on slave startup.
It should be safe to uncomment when merging up to celosia.
Some output is written, some is not
Finally concluded it's a Perl bug: after running with parallel threads
for a while, print suddenly ignores all but the first argument.
Workaround: concatenate all the arguments into one, except in output that
only comes before we start running tests
- disabled main.innodb_bug47777.test with InnoDB plugin
until fix for plugin is applied.
- disabled main.innodb-autoinc.test (failing)
- re-enabled main.innodb_bug39438.test
- added error message suppression to innodb_bug39438, as
requested by InnoDB/Oracle
- reverted change to main.innodb_bug34300 as plugin specific.
The reason for the bug is that mysqtest as well as other client tools
running in test suite (mysqlbinlog, mysqldump) will first try to connect
whatever database has created shared memory with default base name
"MySQL" and use this. (Same effect could be seen on Unix if mtr would
not care to calculate "port" and "socket" parameter).
The fix ensures that all client tools and running in mtr use unique
per-database shared memory base parameters, so there is no possibility
to clash with already installed one. We use socket name for shared memory
base (it's known to be unique). This shared-memory-base is written to the
MTR config file to the [client] and [mysqld] sections. Fix made also made
sure all client tools understand and correctly handle --shared-memory-base.
Prior to this patch it was not the case for mysqltest, mysqlbinlog and
mysql_client_test.
All new connections done from mtr scripts via connect() will by default
set shared-memory-base. And finally, there is a possibility to force
shared memory or pipe connection and overwrite shared memory/pipe base name
from within mtr scripts via optional PIPE or SHM modifier. This functionality
was manually backported from 6.0
(original patch http://lists.mysql.com/commits/74749)
