------------------------------------------------------------
revno: 2617.31.7
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: mysql-6.0-runtime
timestamp: Wed 2009-03-25 19:22:00 -0300
message:
WL#4284: Transactional DDL locking

Post-merge fixes for test cases.

2617.31.12, 2617.31.15, 2617.31.15, 2617.31.16, 2617.43.1
- initial changeset that introduced the fix for 
Bug#989 and follow up fixes for all test suite failures
introduced in the initial changeset. 
------------------------------------------------------------
revno: 2617.31.1
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: 4284-6.0
timestamp: Fri 2009-03-06 19:17:00 -0300
message:
Bug#989: If DROP TABLE while there's an active transaction, wrong binlog order
WL#4284: Transactional DDL locking

Currently the MySQL server does not keep metadata locks on
schema objects for the duration of a transaction, thus failing
to guarantee the integrity of the schema objects being used
during the transaction and to protect then from concurrent
DDL operations. This also poses a problem for replication as
a DDL operation might be replicated even thought there are
active transactions using the object being modified.

The solution is to defer the release of metadata locks until
a active transaction is either committed or rolled back. This
prevents other statements from modifying the table for the
entire duration of the transaction. This provides commitment
ordering for guaranteeing serializability across multiple
transactions.

- Incompatible change:

If MySQL's metadata locking system encounters a lock conflict,
the usual schema is to use the try and back-off technique to
avoid deadlocks -- this schema consists in releasing all locks
and trying to acquire them all in one go.

But in a transactional context this algorithm can't be utilized
as its not possible to release locks acquired during the course
of the transaction without breaking the transaction commitments.
To avoid deadlocks in this case, the ER_LOCK_DEADLOCK will be
returned if a lock conflict is encountered during a transaction.

Let's consider an example:

A transaction has two statements that modify table t1, then table
t2, and then commits. The first statement of the transaction will
acquire a shared metadata lock on table t1, and it will be kept
utill COMMIT to ensure serializability.

At the moment when the second statement attempts to acquire a
shared metadata lock on t2, a concurrent ALTER or DROP statement
might have locked t2 exclusively. The prescription of the current
locking protocol is that the acquirer of the shared lock backs off
-- gives up all his current locks and retries. This implies that
the entire multi-statement transaction has to be rolled back.

- Incompatible change:

FLUSH commands such as FLUSH PRIVILEGES and FLUSH TABLES WITH READ
LOCK won't cause locked tables to be implicitly unlocked anymore.

----------------------------------------------------------
revno: 2617.23.22
committer: Konstantin Osipov <kostja@sun.com>
branch nick: mysql-6.0-runtime
timestamp: Wed 2009-03-04 23:29:16 +0300
message:
  WL#4284, "Transactional DDL locking": fix a Windows compilation warning.

------------------------------------------------------------
revno: 2617.23.23
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: mysql-6.0-runtime
timestamp: Thu 2009-03-05 18:39:58 -0300
message:
Fix for broken build: SHARED is defined by Solaris headers.

----------------------------------------------------------
revno: 2617.23.20
committer: Konstantin Osipov <kostja@sun.com>
branch nick: mysql-6.0-runtime
timestamp: Wed 2009-03-04 16:31:31 +0300
message:
  WL#4284 "Transactional DDL locking"
  Review comments: "Objectify" the MDL API.
  MDL_request and MDL_context still need manual construction and
  destruction, since they are used in environment that is averse
  to constructors/destructors.

----------------------------------------------------------
revno: 2617.23.19
committer: Konstantin Osipov <kostja@sun.com>
branch nick: mysql-6.0-runtime
timestamp: Tue 2009-03-03 01:20:44 +0300
message:
  Metadata locking: realign comments. No semantical changes,
  only enforce a bit of the coding style.
This is a review fix for WL#4284 "Transactional DDL locking".

------------------------------------------------------------
revno: 2617.23.18
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: 4284-6.0
timestamp: Mon 2009-03-02 18:18:26 -0300
message:
Bug#989: If DROP TABLE while there's an active transaction, wrong binlog order
WL#4284: Transactional DDL locking

This is a prerequisite patch:

These changes are intended to split lock requests from granted
locks and to allow the memory and lifetime of granted locks to
be managed within the MDL subsystem. Furthermore, tickets can
now be shared and therefore are used to satisfy multiple lock
requests, but only shared locks can be recursive.

The problem is that the MDL subsystem morphs lock requests into
granted locks locks but does not manage the memory and lifetime
of lock requests, and hence, does not manage the memory of
granted locks either. This can be problematic because it puts the
burden of tracking references on the users of the subsystem and
it can't be easily done in transactional contexts where the locks
have to be kept around for the duration of a transaction.

Another issue is that recursive locks (when the context trying to
acquire a lock already holds a lock on the same object) requires
that each time the lock is granted, a unique lock request/granted
lock structure structure must be kept around until the lock is
released. This can lead to memory leaks in transactional contexts
as locks taken during the transaction should only be released at
the end of the transaction. This also leads to unnecessary wake
ups (broadcasts) in the MDL subsystem if the context still holds
a equivalent of the lock being released.

These issues are exacerbated due to the fact that WL#4284 low-level
design says that the implementation should "2) Store metadata locks
in transaction memory root, rather than statement memory root" but
this is not possible because a memory root, as implemented in mysys,
requires all objects allocated from it to be freed all at once.

This patch combines review input and significant code contributions
from Konstantin Osipov (kostja) and Dmitri Lenev (dlenev).

Add two more files to .bzrignore.

Add two more files to .bzrignore.

----------------------------------------------------------
revno: 2617.22.7
committer: Konstantin Osipov <kostja@sun.com>
branch nick: mysql-6.0-runtime
timestamp: Tue 2009-01-27 16:41:58 +0300
message:
  WL#4284 "Transactional DDL locking" review.
  Improve a comment.

revno: 2617.22.4
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: mysql-6.0-runtime
timestamp: Mon 2009-01-26 15:19:14 -0200
message:
Move checks for OPTION_NOT_AUTOCOMMIT | OPTION_BEGIN to a separate
helper function.

------------------------------------------------------------
revno: 3035.4.1
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: 39897-6.0
timestamp: Thu 2009-01-15 12:17:57 -0200
message:
Bug#39897: lock_multi fails in pushbuild: timeout waiting for processlist

The problem is that relying on the "Table lock" thread state in
its current position to detect that a thread is waiting on a lock
is race prone. The "Table lock" state change happens before the
thread actually tries to grab a lock on a table.

The solution is to move the "Table lock" state so that its set
only when a thread is actually going to wait for a lock. The state
change happens after the thread fails to grab the lock (because it
is owned by other thread) and proceeds to wait on a condition.

This is considered part of work related to WL#4284 "Transactional
DDL locking"
Warning: this patch contains an incompatible change. 
When waiting on a lock in thr_lock.c, the server used to display "Locked"
processlist state. After this patch, the state is "Table lock".
The new state was actually intended to be display since year 2002,
when Monty added it. But up until removal of thd->locked boolean
member, this state was ignored by SHOW PROCESSLIST code.  

-----------------------------------------------------------
2497.479.10 Sergei Golubchik    2008-08-27
            proc_info_hook, mysys access to thd->proc_info

This patch is necessary for backport of WL#4284 "Transactional
DDL locking".

------------------------------------------------------------
revno: 2630.22.3
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: 4284-6.0
timestamp: Thu 2008-08-07 22:33:43 -0300
message:
WL#4284: Transactional DDL locking

Make transaction management more modular through a new interface.

The overall objective of this change is to provide groundwork
for the design of transactional DDL locking by cleaning up the
transaction high level API to better distinguish operations implicit
and explicit, and single statement transaction from operations on
the normal transaction.

Having a a high-level interface for transaction management provides
a better base for implementing transactional concepts that are not
always tied to storage engines and also makes it easier to interect
with other higher level modules of the server.

------------------------------------------------------------
revno: 2630.13.17
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: 4284-6.0
timestamp: Sun 2008-07-27 10:14:46 -0300
message:
Post-merge fixes:

Remove dependency on binlog, require not embedded as test uses
the event scheduler and disable abort on error for syntax only
available on servers built with debugging support.

This is a patch in scope of WL#4284 "Transactional DDL locking"

------------------------------------------------------------
revno: 2630.13.16
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: WL#4284
timestamp: Sat 2008-07-26 13:38:20 -0300
message:
WL#4284: Transactional DDL locking

SQL statements' effect on transactions.

Currently the MySQL server and its storage engines are not
capable of rolling back operations that define or modify data
structures (also known as DDL statements) or operations that
alter any of the system tables (the mysql database). Allowing
these group of statements to participate in transactions
is unfeasible at this time (since rollback has no effect
whatsoever on them) and goes against the design of our metadata
locking subsystem.

The solution is to issue implicit commits before and after
those statements execution. This effectively confines each of
those statements to its own special transaction and ensures
that metadata locks taken during this special transaction
are not leaked into posterior statements/transactions.

----------------------------------------------------------
revno: 2630.2.7
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-runtime
timestamp: Wed 2008-06-04 15:18:52 +0400
message:
  Fix a code regression (not observable externally) that I introduced
  in the fix for Bug#26141

(backporting as part of all patches related to WL#3726)

----------------------------------------------------------
revno: 2630.2.23
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-runtime
timestamp: Fri 2008-06-27 21:15:11 +0400
message:
  Add an assert that we never call COMMIT or ROLLBACK while having
  a table lock.

------------------------------------------------------------ 
revno: 2630.13.4
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-runtime
timestamp: Mon 2008-07-07 19:51:20 +0400
message:
  Fixed outdated comment describing mdl_init_lock() function.

------------------------------------------------------------
revno: 2630.4.39
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Thu 2008-06-26 13:08:27 +0400
message:
  Fix warnings about passing pointer to not fully-initialized THD
  object to constructor of base Open_tables_state classe, which
  appeared on Windows and were introduced by one of the patches
  implementing WL#3726 "DDL locking for all metadata objects".

----------------------------------------------------------
revno: 2630.4.38
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-4144
timestamp: Wed 2008-06-25 22:07:06 +0400
message:
  WL#4144 - Lock MERGE engine children.
  Committing a version of the patch merged with WL#3726
  on behalf of Ingo.

  Step #1: Move locking from parent to children.

  MERGE children are now left in the query list of tables
  after inserted there in open_tables(). So they are locked
  by lock_tables() as all other tables are.

  The MERGE parent does not store locks any more. It appears
  in a MYSQL_LOCK with zero lock data. This is kind of a "dummy"
  lock.

  All other lock handling is also done directly on the children.
  To protect against parent or child modifications during LOCK
  TABLES, the children are detached after every statement and
  attached before every statement, even under LOCK TABLES.

  The children table list is removed from the query list of tables
  on every detach and on close of the parent.

  Step #2: Move MERGE specific functionality from SQL layer
  into table handler.

  Functionality moved from SQL layer (mainly sql_base.cc)
  to the table handler (ha_myisammrg.cc).

  Unnecessary code is removed from the SQL layer.

  Step #3: Moved all MERGE specific members from TABLE
  to ha_myisammrg.

  Moved members from TABLE to ha_myisammrg.
  Renamed some mebers.
  Fixed comments.

  Step #4: Valgrind and coverage testing

  Valgrind did not uncover new problems.
  Added purecov comments.

  Added a new test for DATA/INDEX DIRECTORY options.
  Changed handling of ::reset() for non-attached children.
  Fixed the merge-big test.

  Step #5: Fixed crashes detected during review
  Changed detection when to attach/detach.
  Added new tests.

Backport also the fix for Bug#44040 "MySQL allows creating a 
MERGE table upon VIEWs but crashes when using it"

------------------------------------------------------------
revno: 2630.4.37
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Wed 2008-06-25 20:28:57 +0400
message:
  Fix build failure of mysql-6.0-3726 tree on Windows.

  The failure was caused by the fact that sql/mdl.cc was
  using __func__ macro without including sql_profile.h
  header which contained definition of this macro for
  those platforms that miss it.

  This patch solves this problem by moving this define to
  include/my_global.h which makes it available in modules
  which don't/can't include sql/mysql_priv.h.

This is a patch that is part of WL#3726.

----------------------------------------------------------
revno: 2630.4.36
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-3726
timestamp: Wed 2008-06-25 17:03:37 +0400
message:
  As per discussion with Serg and Dmitri, remove the code
  that is trying to emulate LOCK TABLES when locking tables for prelocking.
  This code was worked around by the engines, and has no effect.
  We may still have to do something to ensure that statement-based
  replication is consistent in MVCC engines, or other engines
  that downgrade table level locks, but this will have to be done
  somehow differently.

----------------------------------------------------------
revno: 2630.4.35
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-3726
timestamp: Wed 2008-06-25 16:44:00 +0400
message:
  Fix a MyISAM-specific bug in the new implementation of
  LOCK TABLES (WL#3726).
  If more than one instance of a MyISAM table are open in the
  same connection, all of them must share the same status_param.
  Otherwise, unlock of a table may lead to lost records.
  See also comments in thr_lock.c.

------------------------------------------------------------
revno: 2630.4.33
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Fri 2008-06-20 17:11:20 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After-review fixes in progress.

  Minimized dependency of mdl.cc on other modules (particularly
  made it independant of mysql_priv.h) in order to be able
  write unit tests for metadata locking subsystem.

------------------------------------------------------------
revno: 2630.4.32
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Thu 2008-06-19 16:39:58 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After-review fixes in progress.

  Ensure that metadata locking subsystem properly handles
  out-of-memory conditions. Clarified MDL interface by
  separating release of locks and removal of lock requests
  from the context.

----------------------------------------------------------
revno: 2630.4.31
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-3726
timestamp: Thu 2008-06-12 06:23:08 +0400
message:
  Extend the signature of TABLE_LIST::init_one_table() to 
  initialize lengths

This is part of WL#3726 post-review fixes.

----------------------------------------------------------
revno: 2630.4.30
Konstantin Osipov   2008-06-11
Fix a potential cause of test failures.

----------------------------------------------------------
revno: 2630.10.1
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-lock-tables-tidyup
timestamp: Wed 2008-06-11 15:49:58 +0400
message:
  WL#3726, review fixes.
  Now that we have metadata locks, we don't need to keep a crippled
  TABLE instance in the table cache to indicate that a table is locked.
  Remove all code that used this technique. Instead, rely on metadata
  locks and use the standard open_table() and close_thread_table()
  to manipulate with the table cache tables.
  Removes a list of functions that have become unused (see the comment
  for sql_base.cc for details).
  Under LOCK TABLES, keep a TABLE_LIST instance for each table
  that may be temporarily closed. For that, implement an own class for
  LOCK TABLES mode, Locked_tables_list.

This is a pre-requisite patch for WL#4144.
This is not exactly a backport: there is no new 
online ALTER table in Celosia, so the old alter table
code was changed to work with the new table cache API.

```---------------------------------------------------------
revno: 2630.9.3
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w3
timestamp: Wed 2008-06-11 08:33:36 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

  Changed close_cached_tables() not to flush all unused TABLE
  instances when flushing individual table.
  Renamed expel_table_from_cache() to tdc_remove_table() and
  added enum parameter to be able more explicitly specify type
  of removal, rewrote its code to be more efficient.

******
Backport of:
```

---------------------------------------------------------
revno: 2630.9.4
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w3
timestamp: Wed 2008-06-11 15:53:53 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After-review fixes in progress.

  Minor changes in order to improve code readability
  and simplify debugging.

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).

mysqld crashed in network_init()).

The problem was that current_thd was not ready at that point in mysqld life,
so ER() macro could not be used.

The fix is to use ER_DEFAULT() macro, which is intented for such cases.

------------------------------------------------------------
revno: 2630.9.2
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w3
timestamp: Tue 2008-06-10 18:01:56 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

------------------------------------------------------------ 
revno: 2630.9.1 
committer: Dmitry Lenev <dlenev@mysql.com> 
branch nick: mysql-6.0-3726-w3 
timestamp: Sun 2008-06-08 22:13:58 +0400 
message: 
  WL#3726 "DDL locking for all metadata objects" 
   
  After review fixes in progress. 
   
  Some adjustments to the patch that removes thd->locked_tables

------------------------------------------------------------
revno: 2630.4.27
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Mon 2008-06-09 14:01:19 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

  Changed open_table() to return bool. This allows more easily to
  distinguish cases when this function succeeds but returns no TABLE
  instance (in case of view or in case of special kind of open) from
  cases when we have an error. Pointer to TABLE instance is now
  always returned in TABLE_LIST::table member.

  This change allows to get rid of false assumption in open_tables()
  implementation and makes it more clear.

----------------------------------------------------------
revno: 2630.4.26
committer: Konstantin Osipov <konstantin@mysql.com>
branch nick: mysql-6.0-prelocked_mode-to-push
timestamp: Fri 2008-06-06 23:19:04 +0400
message:
  WL#3726: work on review comments.
  Remove thd->locked_tables. Always store MYSQL_LOCK instances in
  thd->lock.
  Rename thd->prelocked_mode to thd->locked_tables_mode.
  Use thd->locked_tables_mode to determine if we
  are under LOCK TABLES. Update the code to not assume that
  if thd->lock is set, LOCK TABLES mode is off.
  Review comments.

------------------------------------------------------------
revno: 2630.4.25
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w2
timestamp: Fri 2008-06-06 15:32:48 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

  Clarified some comments explaining control flow in
  prepare_for_repair().