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Author SHA1 Message Date
Mats Kindahl
23d8586dbf WL#5030: Split and remove mysql_priv.h 
This patch:

- Moves all definitions from the mysql_priv.h file into
  header files for the component where the variable is
  defined
- Creates header files if the component lacks one
- Eliminates all include directives from mysql_priv.h
- Eliminates all circular include cycles
- Rename time.cc to sql_time.cc
- Rename mysql_priv.h to sql_priv.h
 2010-03-31 16:05:33 +02:00
Mats Kindahl
e409d6f69c WL#5030: Split and remove mysql_priv.h 
This patch:

- Moves all definitions from the mysql_priv.h file into
  header files for the component where the variable is
  defined
- Creates header files if the component lacks one
- Eliminates all include directives from mysql_priv.h
- Eliminates all circular include cycles
- Rename time.cc to sql_time.cc
- Rename mysql_priv.h to sql_priv.h
 2010-03-31 16:05:33 +02:00
Sergey Petrunya
7df026676b Merge MariaDB-5.2 -> MariaDB 5.3 2010-03-20 15:01:47 +03:00
Sergei Golubchik
f09ca00e08 merged 2010-03-15 12:51:23 +01:00
Konstantin Osipov
ea70b6a20a A fix for Bug#49972 "Crash in prepared statements": 
The problem is introduced by WL#4435 "Support OUT-parameters in 
prepared statements".
When a statement that has out parameters was reprepared,
the reprepare request error was ignored, and an
attempt to send out parameters to the client was made.

Since the out parameter list was not initialized in case
of an error, this attempt led to a crash.

Don't try to send out parameters to the client
if an error occurred in statement execution.

sql/sql_prepare.cc:
  Don't try to send out parameters if error.
tests/mysql_client_test.c:
  Re-enable the test case for Bug#49972.
 2010-03-11 16:47:34 +03:00
Konstantin Osipov
42b7812898 A fix for Bug#49972 "Crash in prepared statements": 
The problem is introduced by WL#4435 "Support OUT-parameters in 
prepared statements".
When a statement that has out parameters was reprepared,
the reprepare request error was ignored, and an
attempt to send out parameters to the client was made.

Since the out parameter list was not initialized in case
of an error, this attempt led to a crash.

Don't try to send out parameters to the client
if an error occurred in statement execution.
 2010-03-11 16:47:34 +03:00
unknown
4bf849c23c Merge MySQL 5.1.44 into MariaDB. 2010-03-04 09:03:07 +01:00
Konstantin Osipov
a72f90bc43 Merge next-mr -> next-4284. 
mysql-test/t/disabled.def:
  Restore disabled ssl tests: SSL certificates were updated.
  Disable sp_sync.test, the test case can't work in next-4284.
mysql-test/t/partition_innodb.test:
  Disable parsing of the test case for Bug#47343, 
  the test can not work in next-4284.
mysql-test/t/ps_ddl.test:
  Update results (CREATE TABLE IF NOT EXISTS takes
  into account existence of the temporary table).
 2010-02-06 13:28:06 +03:00
Konstantin Osipov
9c030fe508 Merge next-mr -> next-4284. 2010-02-06 13:28:06 +03:00
Konstantin Osipov
c8555bdb35 Merge next-mr -> next-4284 2010-02-03 16:43:03 +03:00
Konstantin Osipov
b92ab41c5c Merge next-mr -> next-4284 2010-02-03 16:43:03 +03:00
Konstantin Osipov
056ac55aa0 Merge next-mr -> next-4284. 2010-02-03 03:06:42 +03:00
Konstantin Osipov
0ce6d93f85 Merge next-mr -> next-4284. 2010-02-03 03:06:42 +03:00
Dmitry Lenev
eba5d30e67 Implement new type-of-operation-aware metadata locks. 
Add a wait-for graph based deadlock detector to the
MDL subsystem.

Fixes bug #46272 "MySQL 5.4.4, new MDL: unnecessary deadlock" and
bug #37346 "innodb does not detect deadlock between update and
alter table".

The first bug manifested itself as an unwarranted abort of a
transaction with ER_LOCK_DEADLOCK error by a concurrent ALTER
statement, when this transaction tried to repeat use of a
table, which it has already used in a similar fashion before
ALTER started.

The second bug showed up as a deadlock between table-level
locks and InnoDB row locks, which was "detected" only after
innodb_lock_wait_timeout timeout.

A transaction would start using the table and modify a few
rows.
Then ALTER TABLE would come in, and start copying rows
into a temporary table. Eventually it would stumble on
the modified records and get blocked on a row lock.
The first transaction would try to do more updates, and get
blocked on thr_lock.c lock.
This situation of circular wait would only get resolved
by a timeout.

Both these bugs stemmed from inadequate solutions to the
problem of deadlocks occurring between different
locking subsystems.

In the first case we tried to avoid deadlocks between metadata
locking and table-level locking subsystems, when upgrading shared
metadata lock to exclusive one.
Transactions holding the shared lock on the table and waiting for
some table-level lock used to be aborted too aggressively.

We also allowed ALTER TABLE to start in presence of transactions
that modify the subject table. ALTER TABLE acquires
TL_WRITE_ALLOW_READ lock at start, and that block all writes
against the table (naturally, we don't want any writes to be lost
when switching the old and the new table). TL_WRITE_ALLOW_READ
lock, in turn, would block the started transaction on thr_lock.c
lock, should they do more updates. This, again, lead to the need
to abort such transactions.

The second bug occurred simply because we didn't have any
mechanism to detect deadlocks between the table-level locks
in thr_lock.c and row-level locks in InnoDB, other than
innodb_lock_wait_timeout.

This patch solves both these problems by moving lock conflicts
which are causing these deadlocks into the metadata locking
subsystem, thus making it possible to avoid or detect such
deadlocks inside MDL.

To do this we introduce new type-of-operation-aware metadata
locks, which allow MDL subsystem to know not only the fact that
transaction has used or is going to use some object but also what
kind of operation it has carried out or going to carry out on the
object.

This, along with the addition of a special kind of upgradable
metadata lock, allows ALTER TABLE to wait until all
transactions which has updated the table to go away.
This solves the second issue.
Another special type of upgradable metadata lock is acquired
by LOCK TABLE WRITE. This second lock type allows to solve the
first issue, since abortion of table-level locks in event of
DDL under LOCK TABLES becomes also unnecessary.

Below follows the list of incompatible changes introduced by
this patch:

- From now on, ALTER TABLE and CREATE/DROP TRIGGER SQL (i.e. those
  statements that acquire TL_WRITE_ALLOW_READ lock)
  wait for all transactions which has *updated* the table to
  complete.

- From now on, LOCK TABLES ... WRITE, REPAIR/OPTIMIZE TABLE
  (i.e. all statements which acquire TL_WRITE table-level lock) wait
  for all transaction which *updated or read* from the table
  to complete.
  As a consequence, innodb_table_locks=0 option no longer applies
  to LOCK TABLES ... WRITE.

- DROP DATABASE, DROP TABLE, RENAME TABLE no longer abort
  statements or transactions which use tables being dropped or
  renamed, and instead wait for these transactions to complete.

- Since LOCK TABLES WRITE now takes a special metadata lock,
  not compatible with with reads or writes against the subject table
  and transaction-wide, thr_lock.c deadlock avoidance algorithm
  that used to ensure absence of deadlocks between LOCK TABLES
  WRITE and other statements is no longer sufficient, even for
  MyISAM. The wait-for graph based deadlock detector of MDL
  subsystem may sometimes be necessary and is involved. This may
  lead to ER_LOCK_DEADLOCK error produced for multi-statement
  transactions even if these only use MyISAM:

  session 1:         session 2:
  begin;

  update t1 ...      lock table t2 write, t1 write;
                     -- gets a lock on t2, blocks on t1

  update t2 ...
  (ER_LOCK_DEADLOCK)

- Finally,  support of LOW_PRIORITY option for LOCK TABLES ... WRITE
  was abandoned.
  LOCK TABLE ... LOW_PRIORITY WRITE from now on has the same
  priority as the usual LOCK TABLE ... WRITE.
  SELECT HIGH PRIORITY no longer trumps LOCK TABLE ... WRITE  in
  the wait queue.

- We do not take upgradable metadata locks on implicitly
  locked tables. So if one has, say, a view v1 that uses
  table t1, and issues:
  LOCK TABLE v1 WRITE;
  FLUSH TABLE t1; -- (or just 'FLUSH TABLES'),
  an error is produced.
  In order to be able to perform DDL on a table under LOCK TABLES,
  the table must be locked explicitly in the LOCK TABLES list.

mysql-test/include/handler.inc:
  Adjusted test case to trigger an execution path on which bug 41110
  "crash with handler command when used concurrently with alter
  table" and bug 41112 "crash in mysql_ha_close_table/get_lock_data
  with alter table" were originally discovered. Left old test case
  which no longer triggers this execution path for the sake of
  coverage.
  Added test coverage for HANDLER SQL statements and type-aware
  metadata locks.
  Added a test for the global shared lock and HANDLER SQL.
  Updated tests to take into account that the old simple deadlock
  detection heuristics was replaced with a graph-based deadlock
  detector.
mysql-test/r/debug_sync.result:
  Updated results (see debug_sync.test).
mysql-test/r/handler_innodb.result:
  Updated results (see handler.inc test).
mysql-test/r/handler_myisam.result:
  Updated results (see handler.inc test).
mysql-test/r/innodb-lock.result:
  Updated results (see innodb-lock.test).
mysql-test/r/innodb_mysql_lock.result:
  Updated results (see innodb_mysql_lock.test).
mysql-test/r/lock.result:
  Updated results (see lock.test).
mysql-test/r/lock_multi.result:
  Updated results (see lock_multi.test).
mysql-test/r/lock_sync.result:
  Updated results (see lock_sync.test).
mysql-test/r/mdl_sync.result:
  Updated results (see mdl_sync.test).
mysql-test/r/sp-threads.result:
  SHOW PROCESSLIST output has changed due to the fact that waiting
  for LOCK TABLES WRITE now happens within metadata locking
  subsystem.
mysql-test/r/truncate_coverage.result:
  Updated results (see truncate_coverage.test).
mysql-test/suite/funcs_1/datadict/processlist_val.inc:
  SELECT FROM I_S.PROCESSLIST output has changed due to fact that
  waiting for LOCK TABLES WRITE now happens within metadata locking
  subsystem.
mysql-test/suite/funcs_1/r/processlist_val_no_prot.result:
  SELECT FROM I_S.PROCESSLIST output has changed due to fact that
  waiting for LOCK TABLES WRITE now happens within metadata locking
  subsystem.
mysql-test/suite/rpl/t/rpl_sp.test:
  Updated to a new SHOW PROCESSLIST state name.
mysql-test/t/debug_sync.test:
  Use LOCK TABLES READ instead of LOCK TABLES WRITE as the latter
  no longer allows to trigger execution path involving waiting on
  thr_lock.c lock and therefore reaching debug sync-point covered
  by this test.
mysql-test/t/innodb-lock.test:
  Adjusted test case to the fact that innodb_table_locks=0 option is
  no longer supported, since LOCK TABLES WRITE handles all its
  conflicts within MDL subsystem.
mysql-test/t/innodb_mysql_lock.test:
  Added test for bug #37346 "innodb does not detect deadlock between
  update and alter table".
mysql-test/t/lock.test:
  Added test coverage which checks the fact that we no longer support
  DDL under LOCK TABLES on tables which were locked implicitly.
  Adjusted existing test cases accordingly.
mysql-test/t/lock_multi.test:
  Added test for bug #46272 "MySQL 5.4.4, new MDL: unnecessary
  deadlock".  Adjusted other test cases to take into account the
  fact that waiting for LOCK TABLES ... WRITE now happens within MDL
  subsystem.
mysql-test/t/lock_sync.test:
  Since LOCK TABLES ... WRITE now takes SNRW metadata lock for
  tables locked explicitly we have to implicitly lock InnoDB tables
  (through view) to trigger the table-level lock conflict between
  TL_WRITE and TL_WRITE_ALLOW_WRITE.
mysql-test/t/mdl_sync.test:
  Added basic test coverage for type-of-operation-aware metadata
  locks. Also covered with tests some use cases involving HANDLER
  statements in which a deadlock could arise.
  Adjusted existing tests to take type-of-operation-aware MDL into
  account.
mysql-test/t/multi_update.test:
  Update to a new SHOW PROCESSLIST state name.
mysql-test/t/truncate_coverage.test:
  Adjusted test case after making LOCK TABLES WRITE to wait until
  transactions that use the table to be locked are completed.
  Updated to the changed name of DEBUG_SYNC point.
sql/handler.cc:
  Global read lock functionality has been
  moved into a class.
sql/lock.cc:
  Global read lock functionality has been
  moved into a class.
  Updated code to use the new MDL API.
sql/mdl.cc:
  Introduced new type-of-operation aware metadata locks.
  To do this:
  - Changed MDL_lock to use one list for waiting requests and one
    list for granted requests. For each list, added a bitmap
    that holds information what lock types a list contains.
    Added a helper class MDL_lock::List to manipulate with granted
    and waited lists while keeping the bitmaps in sync
    with list contents.
  - Changed lock-compatibility functions to use bitmaps that
    define compatibility.
  - Introduced a graph based deadlock detector inspired by
    waiting_threads.c from Maria implementation.
  - Now that we have a deadlock detector, and no longer have
    a global lock to protect individual lock objects, but rather
    use an rw lock per object, removed redundant code for upgrade,
    and the global read lock. Changed the MDL API to
    no longer require the caller to acquire the global
    intention exclusive lock by means of a separate method.
    Removed a few more methods that became redundant.
  - Removed deadlock detection heuristic, it has been made
    obsolete by the deadlock detector.
  - With operation-type-aware metadata locks, MDL subsystem has
    become aware of potential conflicts between DDL and open
    transactions. This made it possible to remove calls to
    mysql_abort_transactions_with_shared_lock() from acquisition
    paths for exclusive lock and lock upgrade. Now we can simply
    wait for these transactions to complete without fear of
    deadlock. Function mysql_lock_abort() has also become
    unnecessary for all conflicting cases except when a DDL
    conflicts with a connection that has an open HANDLER.
sql/mdl.h:
  Introduced new type-of-operation aware metadata locks.
  Introduced a graph based deadlock detector and supporting
  methods.
  Added comments.
  God rid of redundant API calls.
  Renamed m_lt_or_ha_sentinel to m_trans_sentinel,
  since now it guards the global read lock as well as
  LOCK TABLES and HANDLER locks.
sql/mysql_priv.h:
  Moved the global read lock functionality into a
  class.
  Added MYSQL_OPEN_FORCE_SHARED_MDL flag which forces
  open_tables() to take MDL_SHARED on tables instead of
  metadata locks specified in the parser. We use this to
  allow PREPARE run concurrently in presence of
  LOCK TABLES ... WRITE.
  Added signature for find_table_for_mdl_ugprade().
sql/set_var.cc:
  Global read lock functionality has been
  moved into a class.
sql/sp_head.cc:
  When creating TABLE_LIST elements for prelocking or
  system tables set the type of request for metadata
  lock according to the operation that will be performed
  on the table.
sql/sql_base.cc:
  - Updated code to use the new MDL API.
  - In order to avoid locks starvation we take upgradable
    locks all at once. As result implicitly locked tables no
    longer get an upgradable lock. Consequently DDL and FLUSH
    TABLES for such tables is prohibited.
    find_write_locked_table() was replaced by
    find_table_for_mdl_upgrade() function.
    open_table() was adjusted to return TABLE instance with
    upgradable ticket when necessary.
  - We no longer wait for all locks on OT_WAIT back off
    action -- only on the lock that caused the wait
    conflict. Moreover, now we distinguish cases when we
    have to wait due to conflict in MDL and old version
    of table in TDC.
  - Upate mysql_notify_threads_having_share_locks()
    to only abort thr_lock.c waits of threads that
    have open HANDLERs, since lock conflicts with only
    these threads now can lead to deadlocks not detectable
    by the MDL deadlock detector.
  - Remove mysql_abort_transactions_with_shared_locks()
    which is no longer needed.
sql/sql_class.cc:
  Global read lock functionality has been moved into a class.
  Re-arranged code in THD::cleanup() to simplify assert.
sql/sql_class.h:
  Introduced class to incapsulate global read lock
  functionality.
  Now sentinel in MDL subsystem guards the global read lock
  as well as LOCK TABLES and HANDLER locks. Adjusted code
  accordingly.
sql/sql_db.cc:
  Global read lock functionality has been moved into a class.
sql/sql_delete.cc:
  We no longer acquire upgradable metadata locks on tables
  which are locked by LOCK TABLES implicitly. As result
  TRUNCATE TABLE is no longer allowed for such tables.
  Updated code to use the new MDL API.
sql/sql_handler.cc:
  Inform MDL_context about presence of open HANDLERs.
  Since HANLDERs break MDL protocol by acquiring table-level
  lock while holding only S metadata lock on a table MDL
  subsystem should take special care about such contexts (Now
  this is the only case when mysql_lock_abort() is used).
sql/sql_parse.cc:
  Global read lock functionality has been moved into a class.
  Do not take upgradable metadata locks when opening tables
  for CREATE TABLE SELECT as it is not necessary and limits
  concurrency.
  When initializing TABLE_LIST objects before adding them
  to the table list set the type of request for metadata lock
  according to the operation that will be performed on the
  table.
  We no longer acquire upgradable metadata locks on tables
  which are locked by LOCK TABLES implicitly. As result FLUSH
  TABLES is no longer allowed for such tables.
sql/sql_prepare.cc:
  Use MYSQL_OPEN_FORCE_SHARED_MDL flag when opening
  tables during PREPARE. This allows PREPARE to run
  concurrently in presence of LOCK TABLES ... WRITE.
sql/sql_rename.cc:
  Global read lock functionality has been moved into a class.
sql/sql_show.cc:
  Updated code to use the new MDL API.
sql/sql_table.cc:
  Global read lock functionality has been moved into a class.
  We no longer acquire upgradable metadata locks on tables
  which are locked by LOCK TABLES implicitly. As result DROP
  TABLE is no longer allowed for such tables.
  Updated code to use the new MDL API.
sql/sql_trigger.cc:
  Global read lock functionality has been moved into a class.
  We no longer acquire upgradable metadata locks on tables
  which are locked by LOCK TABLES implicitly. As result
  CREATE/DROP TRIGGER is no longer allowed for such tables.
  Updated code to use the new MDL API.
sql/sql_view.cc:
  Global read lock functionality has been moved into a class.
  Fixed results of wrong merge that led to misuse of GLR API.
  CREATE VIEW statement is not a commit statement.
sql/table.cc:
  When resetting TABLE_LIST objects for PS or SP re-execution
  set the type of request for metadata lock according to the
  operation that will be performed on the table. Do the same
  in auxiliary function initializing metadata lock requests
  in a table list.
sql/table.h:
  When initializing TABLE_LIST objects set the type of request
  for metadata lock according to the operation that will be
  performed on the table.
sql/transaction.cc:
  Global read lock functionality has been moved into a class.
 2010-02-01 14:43:06 +03:00
Dmitry Lenev
afd15c43a9 Implement new type-of-operation-aware metadata locks. 
Add a wait-for graph based deadlock detector to the
MDL subsystem.

Fixes bug #46272 "MySQL 5.4.4, new MDL: unnecessary deadlock" and
bug #37346 "innodb does not detect deadlock between update and
alter table".

The first bug manifested itself as an unwarranted abort of a
transaction with ER_LOCK_DEADLOCK error by a concurrent ALTER
statement, when this transaction tried to repeat use of a
table, which it has already used in a similar fashion before
ALTER started.

The second bug showed up as a deadlock between table-level
locks and InnoDB row locks, which was "detected" only after
innodb_lock_wait_timeout timeout.

A transaction would start using the table and modify a few
rows.
Then ALTER TABLE would come in, and start copying rows
into a temporary table. Eventually it would stumble on
the modified records and get blocked on a row lock.
The first transaction would try to do more updates, and get
blocked on thr_lock.c lock.
This situation of circular wait would only get resolved
by a timeout.

Both these bugs stemmed from inadequate solutions to the
problem of deadlocks occurring between different
locking subsystems.

In the first case we tried to avoid deadlocks between metadata
locking and table-level locking subsystems, when upgrading shared
metadata lock to exclusive one.
Transactions holding the shared lock on the table and waiting for
some table-level lock used to be aborted too aggressively.

We also allowed ALTER TABLE to start in presence of transactions
that modify the subject table. ALTER TABLE acquires
TL_WRITE_ALLOW_READ lock at start, and that block all writes
against the table (naturally, we don't want any writes to be lost
when switching the old and the new table). TL_WRITE_ALLOW_READ
lock, in turn, would block the started transaction on thr_lock.c
lock, should they do more updates. This, again, lead to the need
to abort such transactions.

The second bug occurred simply because we didn't have any
mechanism to detect deadlocks between the table-level locks
in thr_lock.c and row-level locks in InnoDB, other than
innodb_lock_wait_timeout.

This patch solves both these problems by moving lock conflicts
which are causing these deadlocks into the metadata locking
subsystem, thus making it possible to avoid or detect such
deadlocks inside MDL.

To do this we introduce new type-of-operation-aware metadata
locks, which allow MDL subsystem to know not only the fact that
transaction has used or is going to use some object but also what
kind of operation it has carried out or going to carry out on the
object.

This, along with the addition of a special kind of upgradable
metadata lock, allows ALTER TABLE to wait until all
transactions which has updated the table to go away.
This solves the second issue.
Another special type of upgradable metadata lock is acquired
by LOCK TABLE WRITE. This second lock type allows to solve the
first issue, since abortion of table-level locks in event of
DDL under LOCK TABLES becomes also unnecessary.

Below follows the list of incompatible changes introduced by
this patch:

- From now on, ALTER TABLE and CREATE/DROP TRIGGER SQL (i.e. those
  statements that acquire TL_WRITE_ALLOW_READ lock)
  wait for all transactions which has *updated* the table to
  complete.

- From now on, LOCK TABLES ... WRITE, REPAIR/OPTIMIZE TABLE
  (i.e. all statements which acquire TL_WRITE table-level lock) wait
  for all transaction which *updated or read* from the table
  to complete.
  As a consequence, innodb_table_locks=0 option no longer applies
  to LOCK TABLES ... WRITE.

- DROP DATABASE, DROP TABLE, RENAME TABLE no longer abort
  statements or transactions which use tables being dropped or
  renamed, and instead wait for these transactions to complete.

- Since LOCK TABLES WRITE now takes a special metadata lock,
  not compatible with with reads or writes against the subject table
  and transaction-wide, thr_lock.c deadlock avoidance algorithm
  that used to ensure absence of deadlocks between LOCK TABLES
  WRITE and other statements is no longer sufficient, even for
  MyISAM. The wait-for graph based deadlock detector of MDL
  subsystem may sometimes be necessary and is involved. This may
  lead to ER_LOCK_DEADLOCK error produced for multi-statement
  transactions even if these only use MyISAM:

  session 1:         session 2:
  begin;

  update t1 ...      lock table t2 write, t1 write;
                     -- gets a lock on t2, blocks on t1

  update t2 ...
  (ER_LOCK_DEADLOCK)

- Finally,  support of LOW_PRIORITY option for LOCK TABLES ... WRITE
  was abandoned.
  LOCK TABLE ... LOW_PRIORITY WRITE from now on has the same
  priority as the usual LOCK TABLE ... WRITE.
  SELECT HIGH PRIORITY no longer trumps LOCK TABLE ... WRITE  in
  the wait queue.

- We do not take upgradable metadata locks on implicitly
  locked tables. So if one has, say, a view v1 that uses
  table t1, and issues:
  LOCK TABLE v1 WRITE;
  FLUSH TABLE t1; -- (or just 'FLUSH TABLES'),
  an error is produced.
  In order to be able to perform DDL on a table under LOCK TABLES,
  the table must be locked explicitly in the LOCK TABLES list.
 2010-02-01 14:43:06 +03:00
Alexander Nozdrin
992fc07377 Auto-merge from mysql-trunk-merge. 2010-01-27 22:35:04 +03:00
Alexander Nozdrin
32ab87c385 Auto-merge from mysql-trunk-merge. 2010-01-27 22:35:04 +03:00
Sergey Petrunya
b83cb52e9e Backport of subquery optimizations to 5.3. 
There are still test failures because of:
- Wrong query results in outer join + semi join
- EXPLAIN output differences
 2010-01-17 17:51:10 +03:00
unknown
377d710296 BUG#47418 RBR fails, failure with mixup of base/temporary/view 
'CREATE TABLE IF NOT EXISTS ... SELECT' statement were causing 'CREATE
TEMPORARY TABLE ...' to be written to the binary log in row-based 
mode (a.k.a. RBR), when there was a temporary table with the same name.
Because the 'CREATE TABLE ... SELECT' statement was executed as 
'INSERT ... SELECT' into the temporary table. Since in RBR mode no 
other statements related to temporary tables are written into binary log,
this sometimes broke replication.

This patch changes behavior of 'CREATE TABLE [IF NOT EXISTS] ... SELECT ...'.
it ignores existence of temporary table with the 
same name as table being created and is interpreted
as attempt to create/insert into base table. This makes behavior of
'CREATE TABLE [IF NOT EXISTS] ... SELECT' consistent with
how ordinary 'CREATE TABLE' and 'CREATE TABLE ... LIKE' behave.
 2010-01-16 15:44:24 +08:00
6f380d1650 BUG#47418 RBR fails, failure with mixup of base/temporary/view 
'CREATE TABLE IF NOT EXISTS ... SELECT' statement were causing 'CREATE
TEMPORARY TABLE ...' to be written to the binary log in row-based 
mode (a.k.a. RBR), when there was a temporary table with the same name.
Because the 'CREATE TABLE ... SELECT' statement was executed as 
'INSERT ... SELECT' into the temporary table. Since in RBR mode no 
other statements related to temporary tables are written into binary log,
this sometimes broke replication.

This patch changes behavior of 'CREATE TABLE [IF NOT EXISTS] ... SELECT ...'.
it ignores existence of temporary table with the 
same name as table being created and is interpreted
as attempt to create/insert into base table. This makes behavior of
'CREATE TABLE [IF NOT EXISTS] ... SELECT' consistent with
how ordinary 'CREATE TABLE' and 'CREATE TABLE ... LIKE' behave.
 2010-01-16 15:44:24 +08:00
Tor Didriksen
be634ee66e Backport of 
Bug#45523 "Objects of class base_ilist should not be copyable".
               
Suppress the compiler-generated public copy constructor
and assignment operator of class base_ilist; instead, implement
move_elements_to() function which transfers ownership of elements
from one list to another.
 2010-01-12 12:32:55 +01:00
Tor Didriksen
6766c0d676 Backport of 
Bug#45523 "Objects of class base_ilist should not be copyable".
               
Suppress the compiler-generated public copy constructor
and assignment operator of class base_ilist; instead, implement
move_elements_to() function which transfers ownership of elements
from one list to another.
 2010-01-12 12:32:55 +01:00
Marc Alff
3d91522561 WL#2360 Performance schema 
Part IV: sql instrumentation
 2010-01-06 22:42:07 -07:00
Marc Alff
a4c3bc618b WL#2360 Performance schema 
Part IV: sql instrumentation
 2010-01-06 22:42:07 -07:00
Konstantin Osipov
bf9c1b7353 Apply and review: 
3655 Jon Olav Hauglid   2009-10-19
Bug #30977 Concurrent statement using stored function and DROP FUNCTION 
           breaks SBR
Bug #48246 assert in close_thread_table

Implement a fix for:
Bug #41804 purge stored procedure cache causes mysterious hang for many
           minutes
Bug #49972 Crash in prepared statements

The problem was that concurrent execution of DML statements that
use stored functions and DDL statements that drop/modify the same
function might result in incorrect binary log in statement (and
mixed) mode and therefore break replication.

This patch fixes the problem by introducing metadata locking for
stored procedures and functions. This is similar to what is done
in Bug#25144 for views. Procedures and functions now are
locked using metadata locks until the transaction is either
committed or rolled back. This prevents other statements from
modifying the procedure/function while it is being executed. This
provides commit ordering - guaranteeing serializability across
multiple transactions and thus fixes the reported binlog problem.

Note that we do not take locks for top-level CALLs. This means
that procedures called directly are not protected from changes by
simultaneous DDL operations so they are executed at the state they
had at the time of the CALL. By not taking locks for top-level
CALLs, we still allow transactions to be started inside
procedures.

This patch also changes stored procedure cache invalidation.
Upon a change of cache version, we no longer invalidate the entire
cache, but only those routines which we use, only when a statement
is executed that uses them.

This patch also changes the logic of prepared statement validation.
A stored procedure used by a prepared statement is now validated
only once a metadata lock has been acquired. A version mismatch
causes a flush of the obsolete routine from the cache and
statement reprepare.
Incompatible changes:
1) ER_LOCK_DEADLOCK is reported for a transaction trying to access
   a procedure/function that is locked by a DDL operation in
   another connection.

2) Procedure/function DDL operations are now prohibited in LOCK
   TABLES mode as exclusive locks must be taken all at once and
   LOCK TABLES provides no way to specifiy procedures/functions to
   be locked.

Test cases have been added to sp-lock.test and rpl_sp.test.

Work on this bug has very much been a team effort and this patch
includes and is based on contributions from Davi Arnaut, Dmitry
Lenev, Magne Mæhre and Konstantin Osipov.


mysql-test/r/ps_ddl.result:
  Update results (Bug#30977).
mysql-test/r/ps_ddl1.result:
  Update results (Bug#30977).
mysql-test/r/sp-error.result:
  Update results (Bug#30977).
mysql-test/r/sp-lock.result:
  Update results (Bug#30977).
mysql-test/suite/rpl/r/rpl_sp.result:
  Update results (Bug#30977).
mysql-test/suite/rpl/t/rpl_sp.test:
  Add a test case for Bug#30977.
mysql-test/t/ps_ddl.test:
  Update comments. We no longer re-prepare a prepared statement
  when a stored procedure used in top-level CALL is changed.
mysql-test/t/ps_ddl1.test:
  Modifying stored procedure p1 no longer invalidates prepared
  statement "call p1" -- we can re-use the prepared statement
  without invalidation.
mysql-test/t/sp-error.test:
  Use a constant for an error value.
mysql-test/t/sp-lock.test:
  Add test coverage for Bug#30977.
sql/lock.cc:
  Implement lock_routine_name() - a way to acquire an 
  exclusive metadata lock (ex- name-lock) on 
  stored procedure/function.
sql/sp.cc:
  Change semantics of sp_cache_routine() -- now it has an option
  to make sure that the routine that is cached is up to date (has
  the latest sp cache version).
  
  Add sp_cache_invalidate() to sp_drop_routine(), where it was
  missing (a bug!).
  
  Acquire metadata locks for SP DDL (ALTER/CREATE/DROP). This is
  the core of the fix for Bug#30977.
  
  Since caching and cache invalidation scheme was changed, make 
  sure we don't invalidate the SP cache in the middle of a stored
  routine execution. At the same time, make sure we don't access
  stale data due to lack of invalidation. 
  For that, change ALTER FUNCTION/PROCEDURE to not use the cache,
  and SHOW PROCEDURE CODE/SHOW CREATE PROCEDURE/FUNCTION to always
  read an up to date version of the routine from the cache.
sql/sp.h:
  Add a helper wrapper around sp_cache_routine().
sql/sp_cache.cc:
  Implement new sp_cache_version() and sp_cache_flush_obsolete().
  Now we flush stale routines individually, rather than all at once.
sql/sp_cache.h:
  Update signatures of sp_cache_version() and sp_cache_flush_obsolete().
sql/sp_head.cc:
  Add a default initialization of sp_head::m_sp_cache_version.
  Remove a redundant sp_head::create().
sql/sp_head.h:
  Add m_sp_cache_version to sp_head class - we now 
  keep track of every routine in the stored procedure cache, rather than
  of the entire cache.
sql/sql_base.cc:
  Implement prelocking for stored routines. Validate stored
  routines after they were locked.
  Flush obsolete routines upon next access, one by one, not all at once
  (Bug#41804).
  Style fixes.
sql/sql_class.h:
  Rename a Open_table_context method.
sql/sql_parse.cc:
  Make sure stored procedures DDL commits the active transaction 
  (issues an implicit commit before and after).
  Remove sp_head::create(), a pure redundancy.
  Move the semantical check during alter routine inside sp_update_routine() code in order to:
  - avoid using SP cache during update, it may be obsolete.
  - speed up and simplify the update procedure.
  
  Remove sp_cache_flush_obsolete() calls, we no longer flush the entire
  cache, ever, stale routines are flushed before next use, one at a time.
sql/sql_prepare.cc:
  Move routine metadata validation to open_and_process_routine().
  Fix Bug#49972 (don't swap flags at reprepare).
  Reset Sroutine_hash_entries in reinit_stmt_before_use().
  Remove SP cache invalidation, it's now done by open_tables().
sql/sql_show.cc:
  Fix a warning: remove an unused label.
sql/sql_table.cc:
  Reset mdl_request.ticket for tickets acquired for routines inlined
  through a view, in CHECK TABLE statement, to satisfy an MDL assert.
sql/sql_update.cc:
  Move the cleanup of "translation items" to close_tables_for_reopen(),
  since it's needed in all cases when we back off, not just
  the back-off in multi-update. This fixes a bug when the server
  would crash on attempt to back off when opening tables
  for a statement that uses information_schema tables.
 2009-12-29 15:19:05 +03:00
Konstantin Osipov
3b311f399d Apply and review: 
3655 Jon Olav Hauglid   2009-10-19
Bug #30977 Concurrent statement using stored function and DROP FUNCTION 
           breaks SBR
Bug #48246 assert in close_thread_table

Implement a fix for:
Bug #41804 purge stored procedure cache causes mysterious hang for many
           minutes
Bug #49972 Crash in prepared statements

The problem was that concurrent execution of DML statements that
use stored functions and DDL statements that drop/modify the same
function might result in incorrect binary log in statement (and
mixed) mode and therefore break replication.

This patch fixes the problem by introducing metadata locking for
stored procedures and functions. This is similar to what is done
in Bug#25144 for views. Procedures and functions now are
locked using metadata locks until the transaction is either
committed or rolled back. This prevents other statements from
modifying the procedure/function while it is being executed. This
provides commit ordering - guaranteeing serializability across
multiple transactions and thus fixes the reported binlog problem.

Note that we do not take locks for top-level CALLs. This means
that procedures called directly are not protected from changes by
simultaneous DDL operations so they are executed at the state they
had at the time of the CALL. By not taking locks for top-level
CALLs, we still allow transactions to be started inside
procedures.

This patch also changes stored procedure cache invalidation.
Upon a change of cache version, we no longer invalidate the entire
cache, but only those routines which we use, only when a statement
is executed that uses them.

This patch also changes the logic of prepared statement validation.
A stored procedure used by a prepared statement is now validated
only once a metadata lock has been acquired. A version mismatch
causes a flush of the obsolete routine from the cache and
statement reprepare.
Incompatible changes:
1) ER_LOCK_DEADLOCK is reported for a transaction trying to access
   a procedure/function that is locked by a DDL operation in
   another connection.

2) Procedure/function DDL operations are now prohibited in LOCK
   TABLES mode as exclusive locks must be taken all at once and
   LOCK TABLES provides no way to specifiy procedures/functions to
   be locked.

Test cases have been added to sp-lock.test and rpl_sp.test.

Work on this bug has very much been a team effort and this patch
includes and is based on contributions from Davi Arnaut, Dmitry
Lenev, Magne Mæhre and Konstantin Osipov.
 2009-12-29 15:19:05 +03:00
Konstantin Osipov
dfdbc84585 A prerequisite patch for the fix for Bug#46224 
"HANDLER statements within a transaction might lead to deadlocks".
Introduce a notion of a sentinel to MDL_context. A sentinel
is a ticket that separates all tickets in the context into two
groups: before and after it. Currently we can have (and need) only
one designated sentinel -- it separates all locks taken by LOCK
TABLE or HANDLER statement, which must survive COMMIT and ROLLBACK
and all other locks, which must be released at COMMIT or ROLLBACK.
The tricky part is maintaining the sentinel up to date when
someone release its corresponding ticket. This can happen, e.g.
if someone issues DROP TABLE under LOCK TABLES (generally,
see all calls to release_all_locks_for_name()).
MDL_context::release_ticket() is modified to take care of it.

******
A fix and a test case for Bug#46224 "HANDLER statements within a
transaction might lead to deadlocks".

An attempt to mix HANDLER SQL statements, which are transaction-
agnostic, an open multi-statement transaction,
and DDL against the involved tables (in a concurrent connection) 
could lead to a deadlock. The deadlock would occur when
HANDLER OPEN or HANDLER READ would have to wait on a conflicting
metadata lock. If the connection that issued HANDLER statement
also had other metadata locks (say, acquired in scope of a 
transaction), a classical deadlock situation of mutual wait
could occur.

Incompatible change: entering LOCK TABLES mode automatically
closes all open HANDLERs in the current connection.

Incompatible change: previously an attempt to wait on a lock
in a connection that has an open HANDLER statement could wait
indefinitely/deadlock. After this patch, an error ER_LOCK_DEADLOCK
is produced.

The idea of the fix is to merge thd->handler_mdl_context
with the main mdl_context of the connection, used for transactional
locks. This makes deadlock detection possible, since all waits
with locks are "visible" and available to analysis in a single
MDL context of the connection.

Since HANDLER locks and transactional locks have a different life
cycle -- HANDLERs are explicitly open and closed, and so
are HANDLER locks, explicitly acquired and released, whereas
transactional locks "accumulate" till the end of a transaction
and are released only with COMMIT, ROLLBACK and ROLLBACK TO SAVEPOINT,
a concept of "sentinel" was introduced to MDL_context.
All locks, HANDLER and others, reside in the same linked list.
However, a selected element of the list separates locks with
different life cycle. HANDLER locks always reside at the
end of the list, after the sentinel. Transactional locks are
prepended to the beginning of the list, before the sentinel.
Thus, ROLLBACK, COMMIT or ROLLBACK TO SAVEPOINT, only
release those locks that reside before the sentinel. HANDLER locks
must be released explicitly as part of HANDLER CLOSE statement,
or an implicit close. 
The same approach with sentinel
is also employed for LOCK TABLES locks. Since HANDLER and LOCK TABLES
statement has never worked together, the implementation is
made simple and only maintains one sentinel, which is used either
for HANDLER locks, or for LOCK TABLES locks.


mysql-test/include/handler.inc:
  Add test coverage for Bug#46224 "HANDLER statements within a
  transaction might lead to deadlocks".
  Extended HANDLER coverage to cover a mix of HANDLER, transactions
  and DDL statements.
mysql-test/r/handler_innodb.result:
  Update results (Bug#46224).
mysql-test/r/handler_myisam.result:
  Update results (Bug#46224).
sql/lock.cc:
  Remove thd->some_tables_deleted, it's never used.
sql/log_event.cc:
  No need to check for thd->locked_tables_mode, 
  it's done inside release_transactional_locks().
sql/mdl.cc:
  Implement the concept of HANDLER and LOCK TABLES "sentinel".
  Implement a method to clone an acquired ticket.
  Do not return tickets beyond the sentinel when acquiring
  locks, create a copy.
  Remove methods to merge and backup MDL_context, they are now
  not used (Hurra!). This opens a path to a proper constructor
  and destructor of class MDL_context (to be done in a separate
  patch).
  Modify find_ticket() to provide information about where
  the ticket position is with regard to the sentinel.
sql/mdl.h:
  Add declarations necessary for the implementation of the concept
  of "sentinel", a dedicated ticket separating transactional and
  non-transactional locks.
sql/mysql_priv.h:
  Add mark_tmp_table_for_reuse() declaration, 
  a function to "close" a single session (temporary) table.
sql/sql_base.cc:
  Remove thd->some_tables_deleted.
  Modify deadlock-prevention asserts and deadlock detection
  heuristics to take into account that from now on HANDLER locks
  reside in the same locking context.
  Add broadcast_refresh() to mysql_notify_thread_having_shared_lock():
  this is necessary for the case when a thread having a shared lock
  is asleep in tdc_wait_for_old_versions(). This situation is only
  possible with HANDLER t1 OPEN; FLUSH TABLE (since all over code paths
  that lead to tdc_wait_for_old_versions() always have an
  empty MDL_context). Previously the server would simply deadlock
  in this situation.
sql/sql_class.cc:
  Remove now unused member "THD::some_tables_deleted". 
  Move mysql_ha_cleanup() a few lines above in THD::cleanup() 
  to make sure that all handlers are closed when it's time to 
  destroy the MDL_context of this connection.
  Remove handler_mdl_context and handler_tables.
sql/sql_class.h:
  Remove THD::handler_tables, THD::handler_mdl_context,
  THD::some_tables_deleted.
sql/sql_handler.cc:
  Remove thd->handler_tables.
  Remove thd->handler_mdl_context.
  Rewrite mysql_ha_open() to have no special provision for MERGE
  tables, now that we don't have to manipulate with thd->handler_tables
  it's easy to do.
  Remove dead code.
  Fix a bug in mysql_ha_flush() when we would always flush
  a temporary HANDLER when mysql_ha_flush() is called (actually
  mysql_ha_flush() never needs to flush temporary tables).
sql/sql_insert.cc:
  Update a comment, no more thd->some_tables_deleted.
sql/sql_parse.cc:
  Implement an incompatible change: entering LOCK TABLES closes
  active HANDLERs, if any.
  Now that we have a sentinel, we don't need to check
  for thd->locked_tables_mode when releasing metadata locks in
  COMMIT/ROLLBACK.
sql/sql_plist.h:
  Add new (now necessary) methods to the list class.
sql/sql_prepare.cc:
  Make sure we don't release HANDLER locks when rollback to a
  savepoint, set to not keep locks taken at PREPARE.
sql/sql_servers.cc:
  Update to a new signature of MDL_context::release_all_locks().
sql/sql_table.cc:
  Remove thd->some_tables_deleted.
sql/transaction.cc:
  Add comments. 
  Make sure rollback to (MDL) savepoint works under LOCK TABLES and
  with HANDLER tables.
 2009-12-22 19:09:15 +03:00
Konstantin Osipov
39a1a50dfb A prerequisite patch for the fix for Bug#46224 
"HANDLER statements within a transaction might lead to deadlocks".
Introduce a notion of a sentinel to MDL_context. A sentinel
is a ticket that separates all tickets in the context into two
groups: before and after it. Currently we can have (and need) only
one designated sentinel -- it separates all locks taken by LOCK
TABLE or HANDLER statement, which must survive COMMIT and ROLLBACK
and all other locks, which must be released at COMMIT or ROLLBACK.
The tricky part is maintaining the sentinel up to date when
someone release its corresponding ticket. This can happen, e.g.
if someone issues DROP TABLE under LOCK TABLES (generally,
see all calls to release_all_locks_for_name()).
MDL_context::release_ticket() is modified to take care of it.

******
A fix and a test case for Bug#46224 "HANDLER statements within a
transaction might lead to deadlocks".

An attempt to mix HANDLER SQL statements, which are transaction-
agnostic, an open multi-statement transaction,
and DDL against the involved tables (in a concurrent connection) 
could lead to a deadlock. The deadlock would occur when
HANDLER OPEN or HANDLER READ would have to wait on a conflicting
metadata lock. If the connection that issued HANDLER statement
also had other metadata locks (say, acquired in scope of a 
transaction), a classical deadlock situation of mutual wait
could occur.

Incompatible change: entering LOCK TABLES mode automatically
closes all open HANDLERs in the current connection.

Incompatible change: previously an attempt to wait on a lock
in a connection that has an open HANDLER statement could wait
indefinitely/deadlock. After this patch, an error ER_LOCK_DEADLOCK
is produced.

The idea of the fix is to merge thd->handler_mdl_context
with the main mdl_context of the connection, used for transactional
locks. This makes deadlock detection possible, since all waits
with locks are "visible" and available to analysis in a single
MDL context of the connection.

Since HANDLER locks and transactional locks have a different life
cycle -- HANDLERs are explicitly open and closed, and so
are HANDLER locks, explicitly acquired and released, whereas
transactional locks "accumulate" till the end of a transaction
and are released only with COMMIT, ROLLBACK and ROLLBACK TO SAVEPOINT,
a concept of "sentinel" was introduced to MDL_context.
All locks, HANDLER and others, reside in the same linked list.
However, a selected element of the list separates locks with
different life cycle. HANDLER locks always reside at the
end of the list, after the sentinel. Transactional locks are
prepended to the beginning of the list, before the sentinel.
Thus, ROLLBACK, COMMIT or ROLLBACK TO SAVEPOINT, only
release those locks that reside before the sentinel. HANDLER locks
must be released explicitly as part of HANDLER CLOSE statement,
or an implicit close. 
The same approach with sentinel
is also employed for LOCK TABLES locks. Since HANDLER and LOCK TABLES
statement has never worked together, the implementation is
made simple and only maintains one sentinel, which is used either
for HANDLER locks, or for LOCK TABLES locks.
 2009-12-22 19:09:15 +03:00
Sergei Golubchik
1ad5bb1a69 WL#4738 streamline/simplify @@variable creation process 
Bug#16565 mysqld --help --verbose does not order variablesBug#20413 sql_slave_skip_counter is not shown in show variables
Bug#20415 Output of mysqld --help --verbose is incomplete
Bug#25430 variable not found in SELECT @@global.ft_max_word_len;
Bug#32902 plugin variables don't know their names
Bug#34599 MySQLD Option and Variable Reference need to be consistent in formatting!
Bug#34829 No default value for variable and setting default does not raise error
Bug#34834 ? Is accepted as a valid sql mode
Bug#34878 Few variables have default value according to documentation but error occurs  
Bug#34883 ft_boolean_syntax cant be assigned from user variable to global var.
Bug#37187 `INFORMATION_SCHEMA`.`GLOBAL_VARIABLES`: inconsistent status
Bug#40988 log_output_basic.test succeeded though syntactically false.
Bug#41010 enum-style command-line options are not honoured (maria.maria-recover fails)
Bug#42103 Setting key_buffer_size to a negative value may lead to very large allocations 
Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
Bug#44797 plugins w/o command-line options have no disabling option in --help
Bug#46314 string system variables don't support expressions
Bug#46470 sys_vars.max_binlog_cache_size_basic_32 is broken
Bug#46586 When using the plugin interface the type "set" for options caused a crash.
Bug#47212 Crash in DBUG_PRINT in mysqltest.cc when trying to print octal number
Bug#48758 mysqltest crashes on sys_vars.collation_server_basic in gcov builds
Bug#49417 some complaints about mysqld --help --verbose output
Bug#49540 DEFAULT value of binlog_format isn't the default value
Bug#49640 ambiguous option '--skip-skip-myisam' (double skip prefix)
Bug#49644 init_connect and \0
Bug#49645 init_slave and multi-byte characters
Bug#49646 mysql --show-warnings crashes when server dies


CMakeLists.txt:
  Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
client/mysql.cc:
  don't crash with --show-warnings when mysqld dies
config/ac-macros/plugins.m4:
  Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
include/my_getopt.h:
  comments
include/my_pthread.h:
  fix double #define
mysql-test/mysql-test-run.pl:
  run sys_vars suite by default
  properly recognize envirinment variables (e.g. MTR_MAX_SAVE_CORE) set to 0
  escape gdb command line arguments
mysql-test/suite/sys_vars/r/rpl_init_slave_func.result:
  init_slave+utf8 bug
mysql-test/suite/sys_vars/t/rpl_init_slave_func.test:
  init_slave+utf8 bug
mysys/my_getopt.c:
  Bug#34599 MySQLD Option and Variable Reference need to be consistent in formatting!
  Bug#46586 When using the plugin interface the type "set" for options caused a crash.
  Bug#49640 ambiguous option '--skip-skip-myisam' (double skip prefix)
mysys/typelib.c:
  support for flagset
sql/ha_ndbcluster.cc:
  backport from telco tree
sql/item_func.cc:
  Bug#49644 init_connect and \0
  Bug#49645 init_slave and multi-byte characters
sql/sql_builtin.cc.in:
  Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
sql/sql_plugin.cc:
  Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
  Bug#32902 plugin variables don't know their names
  Bug#44797 plugins w/o command-line options have no disabling option in --help
sql/sys_vars.cc:
  all server variables are defined here
storage/myisam/ft_parser.c:
  remove unnecessary updates of param->quot
storage/myisam/ha_myisam.cc:
  myisam_* variables belong here
strings/my_vsnprintf.c:
  %o and %llx
unittest/mysys/my_vsnprintf-t.c:
  %o and %llx tests
vio/viosocket.c:
  bugfix: fix @@wait_timeout to work with socket timeouts (vs. alarm thread)
 2009-12-22 10:35:56 +01:00
Sergei Golubchik
ae2768ce9c WL#4738 streamline/simplify @@variable creation process 
Bug#16565 mysqld --help --verbose does not order variablesBug#20413 sql_slave_skip_counter is not shown in show variables
Bug#20415 Output of mysqld --help --verbose is incomplete
Bug#25430 variable not found in SELECT @@global.ft_max_word_len;
Bug#32902 plugin variables don't know their names
Bug#34599 MySQLD Option and Variable Reference need to be consistent in formatting!
Bug#34829 No default value for variable and setting default does not raise error
Bug#34834 ? Is accepted as a valid sql mode
Bug#34878 Few variables have default value according to documentation but error occurs  
Bug#34883 ft_boolean_syntax cant be assigned from user variable to global var.
Bug#37187 `INFORMATION_SCHEMA`.`GLOBAL_VARIABLES`: inconsistent status
Bug#40988 log_output_basic.test succeeded though syntactically false.
Bug#41010 enum-style command-line options are not honoured (maria.maria-recover fails)
Bug#42103 Setting key_buffer_size to a negative value may lead to very large allocations 
Bug#44691 Some plugins configured as MYSQL_PLUGIN_MANDATORY in can be disabled
Bug#44797 plugins w/o command-line options have no disabling option in --help
Bug#46314 string system variables don't support expressions
Bug#46470 sys_vars.max_binlog_cache_size_basic_32 is broken
Bug#46586 When using the plugin interface the type "set" for options caused a crash.
Bug#47212 Crash in DBUG_PRINT in mysqltest.cc when trying to print octal number
Bug#48758 mysqltest crashes on sys_vars.collation_server_basic in gcov builds
Bug#49417 some complaints about mysqld --help --verbose output
Bug#49540 DEFAULT value of binlog_format isn't the default value
Bug#49640 ambiguous option '--skip-skip-myisam' (double skip prefix)
Bug#49644 init_connect and \0
Bug#49645 init_slave and multi-byte characters
Bug#49646 mysql --show-warnings crashes when server dies
 2009-12-22 10:35:56 +01:00
Jon Olav Hauglid
5e1dfa4c06 Backport of revno: 2617.71.1 
Bug#42546 Backup: RESTORE fails, thinking it finds an existing table

The problem occured when a MDL locking conflict happened for a non-existent 
table between a CREATE and a INSERT statement. The code for CREATE 
interpreted this lock conflict to mean that the table existed, 
which meant that the statement failed when it should not have.
The problem could occur for CREATE TABLE, CREATE TABLE LIKE and
ALTER TABLE RENAME.

This patch fixes the problem for CREATE TABLE and CREATE TABLE LIKE.
It is based on code backported from the mysql-6.1-fk tree written
by Dmitry Lenev. CREATE now uses normal open_and_lock_tables() code 
to acquire exclusive locks. This means that for the test case in the bug 
description, CREATE will wait until INSERT completes so that it can 
get the exclusive lock. This resolves the reported bug.

The patch also prohibits CREATE TABLE and CREATE TABLE LIKE under 
LOCK TABLES. Note that this is an incompatible change and must 
be reflected in the documentation. Affected test cases have been
updated.

mdl_sync.test contains tests for CREATE TABLE and CREATE TABLE LIKE.

Fixing the issue for ALTER TABLE RENAME is beyond the scope of this
patch. ALTER TABLE cannot be prohibited from working under LOCK TABLES
as this could seriously impact customers and a proper fix would require
a significant rewrite.
 2009-12-10 11:53:20 +01:00
Jon Olav Hauglid
b20a409c38 Backport of revno: 2617.71.1 
Bug#42546 Backup: RESTORE fails, thinking it finds an existing table

The problem occured when a MDL locking conflict happened for a non-existent 
table between a CREATE and a INSERT statement. The code for CREATE 
interpreted this lock conflict to mean that the table existed, 
which meant that the statement failed when it should not have.
The problem could occur for CREATE TABLE, CREATE TABLE LIKE and
ALTER TABLE RENAME.

This patch fixes the problem for CREATE TABLE and CREATE TABLE LIKE.
It is based on code backported from the mysql-6.1-fk tree written
by Dmitry Lenev. CREATE now uses normal open_and_lock_tables() code 
to acquire exclusive locks. This means that for the test case in the bug 
description, CREATE will wait until INSERT completes so that it can 
get the exclusive lock. This resolves the reported bug.

The patch also prohibits CREATE TABLE and CREATE TABLE LIKE under 
LOCK TABLES. Note that this is an incompatible change and must 
be reflected in the documentation. Affected test cases have been
updated.

mdl_sync.test contains tests for CREATE TABLE and CREATE TABLE LIKE.

Fixing the issue for ALTER TABLE RENAME is beyond the scope of this
patch. ALTER TABLE cannot be prohibited from working under LOCK TABLES
as this could seriously impact customers and a proper fix would require
a significant rewrite.
 2009-12-10 11:53:20 +01:00
unknown
08e4635fba merge 5.1-> 5.2 2009-12-08 23:47:54 +02:00
Konstantin Osipov
a14bbee5ab Backport of revno ## 2617.31.1, 2617.31.3, 2617.31.4, 2617.31.5, 
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.


mysql-test/extra/binlog_tests/drop_table.test:
  Add test case for Bug#989.
mysql-test/extra/binlog_tests/mix_innodb_myisam_binlog.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction.
mysql-test/include/mix1.inc:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction.
mysql-test/include/mix2.inc:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction.
mysql-test/r/flush_block_commit.result:
  Update test case result (WL#4284).
mysql-test/r/flush_block_commit_notembedded.result:
  Update test case result (WL#4284).
mysql-test/r/innodb.result:
  Update test case result (WL#4284).
mysql-test/r/innodb_mysql.result:
  Update test case result (WL#4284).
mysql-test/r/lock.result:
  Add test case result for an effect of WL#4284/Bug#989
  (all locks should be released when a connection terminates).
mysql-test/r/mix2_myisam.result:
  Update test case result (effects of WL#4284/Bug#989).
mysql-test/r/not_embedded_server.result:
  Update test case result (effects of WL#4284/Bug#989).
  Add a test case for interaction of WL#4284 and FLUSH PRIVILEGES.
mysql-test/r/partition_innodb_semi_consistent.result:
  Update test case result (effects of WL#4284/Bug#989).
mysql-test/r/partition_sync.result:
  Temporarily disable the test case for Bug#43867,
  which will be fixed by a subsequent backport.
mysql-test/r/ps.result:
  Add a test case for effect of PREPARE on transactional
  locks: we take a savepoint at beginning of PREAPRE
  and release it at the end. Thus PREPARE does not 
  accumulate metadata locks (Bug#989/WL#4284).
mysql-test/r/read_only_innodb.result:
  Update test case result (effects of WL#4284/Bug#989).
mysql-test/suite/binlog/r/binlog_row_drop_tbl.result:
  Add a test case result (WL#4284/Bug#989).
mysql-test/suite/binlog/r/binlog_row_mix_innodb_myisam.result:
  Update test case result (effects of WL#4284/Bug#989).
mysql-test/suite/binlog/r/binlog_stm_drop_tbl.result:
  Add a test case result (WL#4284/Bug#989).
mysql-test/suite/binlog/r/binlog_stm_mix_innodb_myisam.result:
  Update test case result (effects of WL#4284/Bug#989).
mysql-test/suite/binlog/r/binlog_unsafe.result:
  A side effect of Bug#989 -- slightly different table map ids.
mysql-test/suite/binlog/t/binlog_row_drop_tbl.test:
  Add a test case for WL#4284/Bug#989.
mysql-test/suite/binlog/t/binlog_stm_drop_tbl.test:
  Add a test case for WL#4284/Bug#989.
mysql-test/suite/binlog/t/binlog_stm_row.test:
  Update to the new state name. This
  is actually a follow up to another patch for WL#4284, 
  that changes Locked thread state to Table lock.
mysql-test/suite/ndb/r/ndb_index_ordered.result:
  Remove result for disabled part of the test case.
mysql-test/suite/ndb/t/disabled.def:
  Temporarily disable a test case (Bug#45621).
mysql-test/suite/ndb/t/ndb_index_ordered.test:
  Disable a part of a test case (needs update to
  reflect semantics of Bug#989).
mysql-test/suite/rpl/t/disabled.def:
  Disable tests made meaningless by transactional metadata
  locking.
mysql-test/suite/sys_vars/r/autocommit_func.result:
  Add a commit (Bug#989).
mysql-test/suite/sys_vars/t/autocommit_func.test:
  Add a commit (Bug#989).
mysql-test/t/flush_block_commit.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction.
mysql-test/t/flush_block_commit_notembedded.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction.
  Add a test case for transaction-scope locks and the global
  read lock (Bug#989/WL#4284).
mysql-test/t/innodb.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction
  (effects of Bug#989/WL#4284).
mysql-test/t/lock.test:
  Add a test case for Bug#989/WL#4284.
mysql-test/t/not_embedded_server.test:
  Add a test case for Bug#989/WL#4284.
mysql-test/t/partition_innodb_semi_consistent.test:
  Replace TRUNCATE with DELETE, to not issue
  an implicit commit of a transaction, and not depend
  on metadata locks.
mysql-test/t/partition_sync.test:
  Temporarily disable the test case for Bug#43867,
  which needs a fix to be backported from 6.0.
mysql-test/t/ps.test:
  Add a test case for semantics of PREPARE and transaction-scope
  locks: metadata locks on tables used in PREPARE are enclosed into a
  temporary savepoint, taken at the beginning of PREPARE,
  and released at the end. Thus PREPARE does not effect
  what locks a transaction owns.
mysql-test/t/read_only_innodb.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction 
  (Bug#989/WL#4284).
  
  Wait for the read_only statement to actually flush tables before
  sending other concurrent statements that depend on its state.
mysql-test/t/xa.test:
  Fix test case to reflect the fact that transactions now hold
  metadata locks for the duration of a transaction 
  (Bug#989/WL#4284).
sql/ha_ndbcluster_binlog.cc:
  Backport bits of changes of ha_ndbcluster_binlog.cc
  from 6.0, to fix the failing binlog test suite with
  WL#4284. WL#4284 implementation does not work
  with 5.1 implementation of ndbcluster binlog index.
sql/log_event.cc:
  Release metadata locks after issuing a commit.
sql/mdl.cc:
  Style changes (WL#4284).
sql/mysql_priv.h:
  Rename parameter to match the name used in the definition (WL#4284).
sql/rpl_injector.cc:
  Release metadata locks on commit (WL#4284).
sql/rpl_rli.cc:
  Remove assert made meaningless, metadata locks are released
  at the end of the transaction.
sql/set_var.cc:
  Close tables and release locks if autocommit mode is set.
sql/slave.cc:
  Release metadata locks after a rollback.
sql/sql_acl.cc:
  Don't implicitly unlock locked tables. Issue a implicit commit
  at the end and unlock tables.
sql/sql_base.cc:
  Defer the release of metadata locks when closing tables
  if not required to.
  Issue a deadlock error if the locking protocol requires
  that a transaction re-acquire its locks.
  
  Release metadata locks when closing tables for reopen.
sql/sql_class.cc:
  Release metadata locks if the thread is killed.
sql/sql_parse.cc:
  Release metadata locks after implicitly committing a active
  transaction, or after explicit commits or rollbacks.
sql/sql_plugin.cc:
  
  Allocate MDL request on the stack as the use of the table
  is contained within the function. It will be removed from
  the context once close_thread_tables is called at the end
  of the function.
sql/sql_prepare.cc:
  The problem is that the prepare phase of the CREATE TABLE
  statement takes a exclusive metadata lock lock and this can
  cause a self-deadlock the thread already holds a shared lock
  on the table being that should be created.
  
  The solution is to make the prepare phase take a shared
  metadata lock when preparing a CREATE TABLE statement. The
  execution of the statement will still acquire a exclusive
  lock, but won't cause any problem as it issues a implicit
  commit.
  
  After some discussions with stakeholders it has been decided that
  metadata locks acquired during a PREPARE statement must be released
  once the statement is prepared even if it is prepared within a multi
  statement transaction.
sql/sql_servers.cc:
  Don't implicitly unlock locked tables. Issue a implicit commit
  at the end and unlock tables.
sql/sql_table.cc:
  Close table and release metadata locks after a admin operation.
sql/table.h:
  The problem is that the prepare phase of the CREATE TABLE
  statement takes a exclusive metadata lock lock and this can
  cause a self-deadlock the thread already holds a shared lock
  on the table being that should be created.
  
  The solution is to make the prepare phase take a shared
  metadata lock when preparing a CREATE TABLE statement. The
  execution of the statement will still acquire a exclusive
  lock, but won't cause any problem as it issues a implicit
  commit.
sql/transaction.cc:
  Release metadata locks after the implicitly committed due
  to a new transaction being started. Also, release metadata
  locks acquired after a savepoint if the transaction is rolled
  back to the save point.
  
  The problem is that in some cases transaction-long metadata locks
  could be released before the transaction was committed. This could
  happen when a active transaction was ended by a "START TRANSACTION"
  or "BEGIN" statement, in which case the metadata locks would be
  released before the actual commit of the active transaction.
  
  The solution is to defer the release of metadata locks to after the
  transaction has been implicitly committed. No test case is provided
  as the effort to provide one is too disproportional to the size of
  the fix.
 2009-12-05 02:02:48 +03:00
Konstantin Osipov
0b39c189ba Backport of revno ## 2617.31.1, 2617.31.3, 2617.31.4, 2617.31.5, 
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.
 2009-12-05 02:02:48 +03:00
Konstantin Osipov
cf45b61a6a Backport of: 
------------------------------------------------------------
revno: 2630.4.16
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Thu 2008-05-29 09:45:02 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review changes in progress.

  Tweaked some comments and did some renames to
  avoid ambiguites.


sql/mysql_priv.h:
  Removed name_lock_locked_table() function.
sql/sql_base.cc:
  Got rid of name_lock_locked_table() function after replacing
  the only call to it with its body.
  Simplified open_table() code by making "action" argument
  mandatory (i.e. one now should always pass non-0 pointer
  in this argument).
  Renamed TABLE_LIST::open_table_type to open_type to
  avoid confusing it with type of table.
  Adjusted comments according to review.
sql/sql_handler.cc:
  Added comment clarifying in which cases we can have TABLE::mdl_lock
  set to 0.
sql/sql_insert.cc:
  Now the 4th argument of open_table() is mandatory (it makes
  no sense to complicate open_table() code when we can simply
  pass dummy variable).
sql/sql_parse.cc:
  Renamed TABLE_LIST::open_table_type to open_type to
  avoid confusing it with type of table.
sql/sql_prepare.cc:
  Renamed TABLE_LIST::open_table_type to open_type to
  avoid confusing it with type of table.
sql/sql_table.cc:
  Now the 4th argument of open_table() is mandatory (it makes
  no sense to complicate open_table() code when we can simply
  pass dummy variable).
sql/sql_trigger.cc:
  Replaced the only call to name_lock_locked_table() function
  with its body.
sql/sql_view.cc:
  Renamed TABLE_LIST::open_table_type to open_type to
  avoid confusing it with type of table.
sql/table.h:
  Renamed TABLE_LIST::open_table_type to open_type (to
  avoid confusing it with type of table) and improved
  comments describing this member.
 2009-12-01 01:13:06 +03:00
Konstantin Osipov
f56cc2a335 Backport of: 
------------------------------------------------------------
revno: 2630.4.16
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Thu 2008-05-29 09:45:02 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review changes in progress.

  Tweaked some comments and did some renames to
  avoid ambiguites.
 2009-12-01 01:13:06 +03:00
Konstantin Osipov
eff3780dd8 Initial import of WL#3726 "DDL locking for all metadata objects". 
Backport of:
------------------------------------------------------------
revno: 2630.4.1
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Fri 2008-05-23 17:54:03 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.
------------------------------------------------------------

This is the first patch in series. It transforms the metadata 
locking subsystem to use a dedicated module (mdl.h,cc). No 
significant changes in the locking protocol. 
The import passes the test suite with the exception of 
deprecated/removed 6.0 features, and MERGE tables. The latter
are subject to a fix by WL#4144.
Unfortunately, the original changeset comments got lost in a merge,
thus this import has its own (largely insufficient) comments.

This patch fixes Bug#25144 "replication / binlog with view breaks".
Warning: this patch introduces an incompatible change:
Under LOCK TABLES, it's no longer possible to FLUSH a table that 
was not locked for WRITE.
Under LOCK TABLES, it's no longer possible to DROP a table or
VIEW that was not locked for WRITE.

******
Backport of:
------------------------------------------------------------
revno: 2630.4.2
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 14:03:45 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

******
Backport of:
------------------------------------------------------------
revno: 2630.4.3
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 14:08:51 +0400
message:
  WL#3726 "DDL locking for all metadata objects"

  Fixed failing Windows builds by adding mdl.cc to the lists
  of files needed to build server/libmysqld on Windows.

******
Backport of:
------------------------------------------------------------
revno: 2630.4.4
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 21:57:58 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  Fix for assert failures in kill.test which occured when one
  tried to kill ALTER TABLE statement on merge table while it
  was waiting in wait_while_table_is_used() for other connections
  to close this table.

  These assert failures stemmed from the fact that cleanup code
  in this case assumed that temporary table representing new
  version of table was open with adding to THD::temporary_tables
  list while code which were opening this temporary table wasn't
  always fulfilling this.

  This patch changes code that opens new version of table to
  always do this linking in. It also streamlines cleanup process
  for cases when error occurs while we have new version of table
  open.

******
WL#3726 "DDL locking for all metadata objects"
Add libmysqld/mdl.cc to .bzrignore.
******
Backport of:
------------------------------------------------------------
revno: 2630.4.6
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sun 2008-05-25 00:33:22 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  Addition to the fix of assert failures in kill.test caused by
  changes for this worklog.


Make sure we close the new table only once.

.bzrignore:
  Add libmysqld/mdl.cc
libmysqld/CMakeLists.txt:
  Added mdl.cc to the list of files needed for building of libmysqld.
libmysqld/Makefile.am:
  Added files implementing new meta-data locking subsystem to the server.
mysql-test/include/handler.inc:
  Use separate connection for waiting while threads performing DDL
  operations conflicting with open HANDLER tables reach blocked
  state. This is required because now we check and close tables open
  by HANDLER statements in this connection conflicting with DDL in
  another each time open_tables() is called and thus select from I_S
  which is used for waiting will unblock DDL operations if issued
  from connection with open HANDLERs.
mysql-test/r/create.result:
  Adjusted test case after change in implementation of CREATE TABLE
  ... SELECT.  We no longer have special check in open_table() which
  catches the case when we select from the table created. Instead we
  rely on unique_table() call which happens after opening and
  locking all tables.
mysql-test/r/flush.result:
  FLUSH TABLES WITH READ LOCK can no longer happen under LOCK
  TABLES.  Updated test accordingly.
mysql-test/r/flush_table.result:
  Under LOCK TABLES we no longer allow to do FLUSH TABLES for tables
  locked for read. Updated test accordingly.
mysql-test/r/handler_innodb.result:
  Use separate connection for waiting while threads performing DDL
  operations conflicting with open HANDLER tables reach blocked
  state. This is required because now we check and close tables open
  by HANDLER statements in this connection conflicting with DDL in
  another each time open_tables() is called and thus select from I_S
  which is used for waiting will unblock DDL operations if issued
  from connection with open HANDLERs.
mysql-test/r/handler_myisam.result:
  Use separate connection for waiting while threads performing DDL
  operations conflicting with open HANDLER tables reach blocked
  state. This is required because now we check and close tables open
  by HANDLER statements in this connection conflicting with DDL in
  another each time open_tables() is called and thus select from I_S
  which is used for waiting will unblock DDL operations if issued
  from connection with open HANDLERs.
mysql-test/r/information_schema.result:
  Additional test for WL#3726 "DDL locking for all metadata
  objects".  Check that we use high-priority metadata lock requests
  when filling I_S tables.
  
  Rearrange tests to match 6.0 better (fewer merge conflicts).
mysql-test/r/kill.result:
  Added tests checking that DDL and DML statements waiting for
  metadata locks can be interrupted by KILL command.
mysql-test/r/lock.result:
  One no longer is allowed to do DROP VIEW under LOCK TABLES even if
  this view is locked by LOCK TABLES. The problem is that in such
  situation write locks on view are not mutually exclusive so
  upgrading metadata lock which is required for dropping of view
  will lead to deadlock.
mysql-test/r/partition_column_prune.result:
  Update results (same results in 6.0), WL#3726
mysql-test/r/partition_pruning.result:
  Update results (same results in 6.0), WL#3726
mysql-test/r/ps_ddl.result:
  We no longer invalidate prepared CREATE TABLE ... SELECT statement
  if target table changes. This is OK since it is not strictly
  necessary.
  
  
  The first change is wrong, is caused by FLUSH TABLE
  now flushing all unused tables. This is a regression that
  Dmitri fixed in 6.0 in a follow up patch.
mysql-test/r/sp.result:
  Under LOCK TABLES we no longer allow accessing views which were
  not explicitly locked. To access view we need to obtain metadata
  lock on it and doing this under LOCK TABLES may lead to deadlocks.
mysql-test/r/view.result:
  One no longer is allowed to do DROP VIEW under LOCK TABLES even if
  this view is locked by LOCK TABLES. The problem is that in such
  situation even "write locks" on view are not mutually exclusive so
  upgrading metadata lock which is required for dropping of view
  will lead to deadlock
mysql-test/r/view_grant.result:
  ALTER VIEW implementation was changed to open a view only after
  checking that user which does alter has appropriate privileges on
  it. This means that in case when user's privileges are
  insufficient for this we won't check that new view definer is the
  same as original one or user performing alter has SUPER privilege.
  Adjusted test case accordingly.
mysql-test/r/view_multi.result:
  Added test case for bug#25144 "replication / binlog with view
  breaks".
mysql-test/suite/rpl/t/disabled.def:
  Disable test for deprecated features (they don't work with new MDL).
mysql-test/t/create.test:
  Adjusted test case after change in implementation of CREATE TABLE
  ... SELECT.  We no longer have special check in open_table() which
  catches the case when we select from the table created. Instead we
  rely on unique_table() call which happens after opening and
  locking all tables.
mysql-test/t/disabled.def:
  Disable merge.test, subject of WL#4144
mysql-test/t/flush.test:
  
  FLUSH TABLES WITH READ LOCK can no longer happen under LOCK
  TABLES.  Updated test accordingly.
mysql-test/t/flush_table.test:
  Under LOCK TABLES we no longer allow to do FLUSH TABLES for tables
  locked for read. Updated test accordingly.
mysql-test/t/information_schema.test:
  Additional test for WL#3726 "DDL locking for all metadata
  objects".  Check that we use high-priority metadata lock requests
  when filling I_S tables.
  
  Rearrange the results for easier merges with 6.0.
mysql-test/t/kill.test:
  Added tests checking that DDL and DML statements waiting for
  metadata locks can be interrupted by KILL command.
mysql-test/t/lock.test:
  One no longer is allowed to do DROP VIEW under LOCK TABLES even if
  this view is locked by LOCK TABLES. The problem is that in such
  situation write locks on view are not mutually exclusive so
  upgrading metadata lock which is required for dropping of view
  will lead to deadlock.
mysql-test/t/lock_multi.test:
  Adjusted test case to the changes of status in various places
  caused by change in implementation FLUSH TABLES WITH READ LOCK,
  which is now takes global metadata lock before flushing tables and
  therefore waits on at these places.
mysql-test/t/ps_ddl.test:
  We no longer invalidate prepared CREATE TABLE ... SELECT statement
  if target table changes. This is OK since it is not strictly
  necessary.
  
  
  The first change is wrong, is caused by FLUSH TABLE
  now flushing all unused tables. This is a regression that
  Dmitri fixed in 6.0 in a follow up patch.
mysql-test/t/sp.test:
  Under LOCK TABLES we no longer allow accessing views which were
  not explicitly locked. To access view we need to obtain metadata
  lock on it and doing this under LOCK TABLES may lead to deadlocks.
mysql-test/t/trigger_notembedded.test:
  Adjusted test case to the changes of status in various places
  caused by change in implementation FLUSH TABLES WITH READ LOCK,
  which is now takes global metadata lock before flushing tables and
  therefore waits on at these places.
mysql-test/t/view.test:
  One no longer is allowed to do DROP VIEW under LOCK TABLES even if
  this view is locked by LOCK TABLES. The problem is that in such
  situation even "write locks" on view are not mutually exclusive so
  upgrading metadata lock which is required for dropping of view
  will lead to deadlock.
mysql-test/t/view_grant.test:
  ALTER VIEW implementation was changed to open a view only after
  checking that user which does alter has appropriate privileges on
  it. This means that in case when user's privileges are
  insufficient for this we won't check that new view definer is the
  same as original one or user performing alter has SUPER privilege.
  Adjusted test case accordingly.
mysql-test/t/view_multi.test:
  Added test case for bug#25144 "replication / binlog with view
  breaks".
sql/CMakeLists.txt:
  Added mdl.cc to the list of files needed for building of server.
sql/Makefile.am:
  Added files implementing new meta-data locking subsystem to the
  server.
sql/event_db_repository.cc:
  
  Allocate metadata lock requests objects (MDL_LOCK) on execution
  memory root in cases when TABLE_LIST objects is also allocated
  there or on stack.
sql/ha_ndbcluster.cc:
  Adjusted code to work nicely with new metadata locking subsystem.
  close_cached_tables() no longer has wait_for_placeholder argument.
  Instead of relying on this parameter and related behavior FLUSH
  TABLES WITH READ LOCK now takes global shared metadata lock.
sql/ha_ndbcluster_binlog.cc:
  Adjusted code to work with new metadata locking subsystem.
  close_cached_tables() no longer has wait_for_placeholder argument.
  Instead of relying on this parameter and related behavior FLUSH
  TABLES WITH READ LOCK now takes global shared metadata lock.
sql/handler.cc:
  update_frm_version():
    Directly update TABLE_SHARE::mysql_version member instead of
    going through all TABLE instances for this table (old code was a
    legacy from pre-table-definition-cache days).
sql/lock.cc:
  Use new metadata locking subsystem. Threw away most of functions
  related to name locking as now one is supposed to use metadata
  locking API instead.  In lock_global_read_lock() and
  unlock_global_read_lock() in order to avoid problems with global
  read lock sneaking in at the moment when we perform FLUSH TABLES
  or ALTER TABLE under LOCK TABLES and when tables being reopened
  are protected only by metadata locks we also have to take global
  shared meta data lock.
sql/log_event.cc:
  Adjusted code to work with new metadata locking subsystem.  For
  tables open by slave thread for applying RBR events allocate
  memory for lock request object in the same chunk of memory as
  TABLE_LIST objects for them. In order to ensure that we keep these
  objects around until tables are open always close tables before
  calling Relay_log_info::clear_tables_to_lock(). Use new auxiliary
  Relay_log_info::slave_close_thread_tables() method to enforce
  this.
sql/log_event_old.cc:
  Adjusted code to work with new metadata locking subsystem.  Since
  for tables open by slave thread for applying RBR events memory for
  lock request object is allocated in the same chunk of memory as
  TABLE_LIST objects for them we have to ensure that we keep these
  objects around until tables are open. To ensure this we always
  close tables before calling
  Relay_log_info::clear_tables_to_lock(). To enfore this we use
  new auxiliary Relay_log_info::slave_close_thread_tables()
  method.
sql/mdl.cc:
  Implemented new metadata locking subsystem and API described in
  WL3726 "DDL locking for all metadata objects".
sql/mdl.h:
  Implemented new metadata locking subsystem and API described in
  WL3726 "DDL locking for all metadata objects".
sql/mysql_priv.h:
  - close_thread_tables()/close_tables_for_reopen() now has one more
    argument which indicates that metadata locks should be released
    but not removed from the context in order to be used later in
    mdl_wait_for_locks() and tdc_wait_for_old_version().
  - close_cached_table() routine is no longer public.
  - Thread waiting in wait_while_table_is_used() can be now killed
    so this function returns boolean to make caller aware of such
    situation.
  - We no longer have  table cache as separate entity instead used
    and unused TABLE instances are linked to TABLE_SHARE objects in
    table definition cache.
  - Now third argument of open_table() is also used for requesting
    table repair or auto-discovery of table's new definition. So its
    type was changed from bool to enum.
  - Added tdc_open_view() function for opening view by getting its
    definition from disk (and table cache in future).
  - reopen_name_locked_table() no longer needs "link_in" argument as
    now we have exclusive metadata locks instead of dummy TABLE
    instances when this function is called.
  - find_locked_table() now takes head of list of TABLE instances
    instead of always scanning through THD::open_tables list. Also
    added find_write_locked_table() auxiliary.
  - reopen_tables(), close_cached_tables() no longer have
    mark_share_as_old and wait_for_placeholder arguments. Instead of
    relying on this parameters and related behavior FLUSH TABLES
    WITH READ LOCK now takes global shared metadata lock.
  - We no longer need drop_locked_tables() and
    abort_locked_tables().
  - mysql_ha_rm_tables() now always assume that LOCK_open is not
    acquired by caller.
  - Added notify_thread_having_shared_lock() callback invoked by
    metadata locking subsystem when acquiring an exclusive lock, for
    each thread that has a conflicting shared metadata lock.
  - Introduced expel_table_from_cache() as replacement for
    remove_table_from_cache() (the main difference is that this new
    function assumes that caller follows metadata locking protocol
    and never waits).
  - Threw away most of functions related to name locking. One should
    use new metadata locking subsystem and API instead.
sql/mysqld.cc:
  Got rid of call initializing/deinitializing table cache since now
  it is embedded into table definition cache. Added calls for
  initializing/ deinitializing metadata locking subsystem.
sql/rpl_rli.cc:
  Introduced auxiliary Relay_log_info::slave_close_thread_tables()
  method which is used for enforcing that we always close tables
  open for RBR before deallocating TABLE_LIST elements and MDL_LOCK
  objects for them.
sql/rpl_rli.h:
  Introduced auxiliary Relay_log_info::slave_close_thread_tables()
  method which is used for enforcing that we always close tables
  open for RBR before deallocating TABLE_LIST elements and MDL_LOCK
  objects for them.
sql/set_var.cc:
  close_cached_tables() no longer has wait_for_placeholder argument.
  Instead of relying on this parameter and related behavior FLUSH
  TABLES WITH READ LOCK now takes global shared metadata lock.
sql/sp_head.cc:
  For tables added to the statement's table list by prelocking
  algorithm we allocate these objects either on the same memory as
  corresponding table list elements or on THD::locked_tables_root
  (if we are building table list for LOCK TABLES).
sql/sql_acl.cc:
  Allocate metadata lock requests objects (MDL_LOCK) on execution
  memory root in cases when we use stack TABLE_LIST objects to open
  tables.  Got rid of redundant code by using unlock_locked_tables()
  function.
sql/sql_base.cc:
  Changed code to use new MDL subsystem. Got rid of separate table
  cache.  Now used and unused TABLE instances are linked to the
  TABLE_SHAREs in table definition cache.
  
  check_unused():
    Adjusted code to the fact that we no longer have separate table
    cache.  Removed dead code.
  table_def_free():
    Free TABLE instances referenced from TABLE_SHARE objects before
    destroying table definition cache.
  get_table_share():
    Added assert which ensures that noone will be able to access
    table (and its share) without acquiring some kind of metadata
    lock first.
  close_handle_and_leave_table_as_lock():
    Adjusted code to the fact that TABLE instances now are linked to
    list in TABLE_SHARE.
  list_open_tables():
    Changed this function to use table definition cache instead of
    table cache.
  free_cache_entry():
    Unlink freed TABLE elements from the list of all TABLE instances
    for the table in TABLE_SHARE.
  kill_delayed_thread_for_table():
    Added auxiliary for killing delayed insert threads for
    particular table.
  close_cached_tables():
    Got rid of wait_for_refresh argument as we now rely on global
    shared metadata lock to prevent FLUSH WITH READ LOCK sneaking in
    when we are reopening tables. Heavily reworked this function to
    use new MDL code and not to rely on separate table cache entity.
  close_open_tables():
    We no longer have separate table cache.
  close_thread_tables():
    Release metadata locks after closing all tables. Added skip_mdl
    argument which allows us not to remove metadata lock requests
    from the context in case when we are going to use this requests
    later in mdl_wait_for_locks() and tdc_wait_for_old_versions().
  close_thread_table()/close_table_for_reopen():
    Since we no longer have separate table cache and all TABLE
    instances are linked to TABLE_SHARE objects in table definition
    cache we have to link/unlink TABLE object to/from appropriate
    lists in the share.
  name_lock_locked_table():
   Moved redundant code to find_write_locked_table() function and
    adjusted code to the fact that wait_while_table_is_used() can
    now return with an error if our thread is killed.
  reopen_table_entry():
    We no longer need "link_in" argument as with MDL we no longer
    call this function with dummy TABLE object pre-allocated and
    added to the THD::open_tables. Also now we add newly-open TABLE
    instance to the list of share's used TABLE instances.
  table_cache_insert_placeholder():
    Got rid of name-locking legacy.
  lock_table_name_if_not_cached():
    Moved to sql_table.cc the only place where it is used. It was
    also reimplemented using new MDL API.
  open_table():
    - Reworked this function to use new MDL subsystem.
    - Changed code to deal with table definition cache directly
      instead of going through separate table cache.
    - Now third argument is also used for requesting table repair
      or auto-discovery of table's new definition. So its type was
      changed from bool to enum.
  find_locked_table()/find_write_locked_table():
    Accept head of list of TABLE objects as first argument and use
    this list instead of always searching in THD::open_tables list.
    Also added auxiliary for finding write-locked locked tables.
  reopen_table():
    Adjusted function to work with new MDL subsystem and to properly
    manuipulate with lists of used/unused TABLE instaces in
    TABLE_SHARE.
  reopen_tables():
    Removed mark_share_as_old parameter. Instead of relying on it
    and related behavior FLUSH TABLES WITH READ LOCK now takes
    global shared metadata lock. Changed code after removing
    separate table cache.
  drop_locked_tables()/abort_locked_tables():
    Got rid of functions which are no longer needed.
    unlock_locked_tables():
    Moved this function from sql_parse.cc and changed it to release
    memory which was used for allocating metadata lock requests for
    tables open and locked by LOCK TABLES.
  tdc_open_view():
    Intoduced function for opening a view by getting its definition
    from disk (and table cache in future).
  reopen_table_entry():
    Introduced function for opening table definitions while holding
    exclusive metatadata lock on it.
  open_unireg_entry():
   Got rid of this function. Most of its functionality is relocated
    to open_table() and open_table_fini() functions, and some of it
    to reopen_table_entry() and tdc_open_view(). Also code
    resposible for auto-repair and auto-discovery of tables was
    moved to separate function.
  open_table_entry_fini():
    Introduced function which contains common actions which finalize
    process of TABLE object creation.
  auto_repair_table():
    Moved code responsible for auto-repair of table being opened
    here.
  handle_failed_open_table_attempt()
    Moved code responsible for handling failing attempt to open
    table to one place (retry due to lock conflict/old version,
    auto-discovery and repair).
  open_tables():
    - Flush open HANDLER tables if they have old version of if there
      is conflicting metadata lock against them (before this moment
      we had this code in open_table()).
    - When we open view which should be processed via derived table
      on the second execution of prepared statement or stored
      routine we still should call open_table() for it in order to
      obtain metadata lock on it and prepare its security context.
    - In cases when we discover that some special handling of
      failure to open table is needed call
      handle_failed_open_table_attempt() which handles all such
      scenarios.
  open_ltable():
    Handling of various special scenarios of failure to open a table
    was moved to separate handle_failed_open_table_attempt()
    function.
  remove_db_from_cache():
    Removed this function as it is no longer used.
  notify_thread_having_shared_lock():
    Added callback which is invoked by MDL subsystem when acquiring
    an exclusive lock, for each thread that has a conflicting shared
    metadata lock.
  expel_table_from_cache():
    Introduced function for removing unused TABLE instances. Unlike
    remove_table_from_cache() it relies on caller following MDL
    protocol and having appropriate locks when calling it and thus
    does not do any waiting if table is still in use.
  tdc_wait_for_old_version():
    Added function which allows open_tables() to wait in cases when
    we discover that we should back-off due to presence of old
    version of table.
  abort_and_upgrade_lock():
    Use new MDL calls.
  mysql_wait_completed_table():
    Got rid of unused function.
  open_system_tables_for_read/for_update()/performance_schema_table():
    Allocate MDL_LOCK objects on execution memory root in cases when
    TABLE_LIST objects for corresponding tables is allocated on
    stack.
  close_performance_schema_table():
    Release metadata locks after closing tables.
  ******
  Use I_P_List for free/used tables list in the table share.
sql/sql_binlog.cc:
  Use Relay_log_info::slave_close_thread_tables() method to enforce
  that we always close tables open for RBR before deallocating
  TABLE_LIST elements and MDL_LOCK objects for them.
sql/sql_class.cc:
  Added meta-data locking contexts as part of Open_tables_state
  context.  Also introduced THD::locked_tables_root memory root
  which is to be used for allocating MDL_LOCK objects for tables in
  LOCK TABLES statement (end of lifetime for such objects is UNLOCK
  TABLES so we can't use statement or execution root for them).
sql/sql_class.h:
  Added meta-data locking contexts as part of Open_tables_state
  context.  Also introduced THD::locked_tables_root memory root
  which is to be used for allocating MDL_LOCK objects for tables in
  LOCK TABLES statement (end of lifetime for such objects is UNLOCK
  TABLES so we can't use statement or execution root for them).
  
  Note: handler_mdl_context and locked_tables_root and
  mdl_el_root will be removed by subsequent patches.
sql/sql_db.cc:
  mysql_rm_db() does not really need to call remove_db_from_cache()
  as it drops each table in the database using
  mysql_rm_table_part2(), which performs all necessary operations on
  table (definition) cache.
sql/sql_delete.cc:
  Use the new metadata locking API for TRUNCATE.
sql/sql_handler.cc:
  Changed HANDLER implementation to use new metadata locking
  subsystem.  Note that MDL_LOCK objects for HANDLER tables are
  allocated in the same chunk of heap memory as TABLE_LIST object
  for those tables.
sql/sql_insert.cc:
  mysql_insert():
    find_locked_table() now takes head of list of TABLE object as
    its argument instead of always scanning through THD::open_tables
    list.
  handle_delayed_insert():
    Allocate metadata lock request object for table open by delayed
    insert thread on execution memroot.  create_table_from_items():
    We no longer allocate dummy TABLE objects for tables being
    created if they don't exist. As consequence
    reopen_name_locked_table() no longer has link_in argument.
    open_table() now has one more argument which is not relevant for
    temporary tables.
sql/sql_parse.cc:
  - Moved unlock_locked_tables() routine to sql_base.cc and made
    available it in other files. Got rid of some redundant code by
    using this function.
  - Replaced boolean TABLE_LIST::create member with enum
    open_table_type member.
  - Use special memory root for allocating MDL_LOCK objects for
    tables open and locked by LOCK TABLES (these object should live
    till UNLOCK TABLES so we can't allocate them on statement nor
    execution memory root). Also properly set metadata lock
    upgradability attribure for those tables.
  - Under LOCK TABLES it is no longer allowed to flush tables which
    are not write-locked as this breaks metadata locking protocol
    and thus potentially might lead to deadlock.
  - Added auxiliary adjust_mdl_locks_upgradability() function.
sql/sql_partition.cc:
  Adjusted code to the fact that reopen_tables() no longer has
  "mark_share_as_old" argument. Got rid of comments which are no
  longer true.
sql/sql_plist.h:
  Added I_P_List template class for parametrized intrusive doubly
  linked lists and I_P_List_iterator for corresponding iterator.
  Unlike for I_List<> list elements of such list can participate in
  several lists. Unlike List<> such lists are doubly-linked and
  intrusive.
sql/sql_plugin.cc:
  Allocate metadata lock requests objects (MDL_LOCK) on execution
  memory root in cases when we use stack TABLE_LIST objects to open
  tables.
sql/sql_prepare.cc:
  Replaced boolean TABLE_LIST::create member with enum
  open_table_type member.  This allows easily handle situation in
  which instead of opening the table we want only to take exclusive
  metadata lock on it.
sql/sql_rename.cc:
  Use new metadata locking subsystem in implementation of RENAME
  TABLE.
sql/sql_servers.cc:
  Allocate metadata lock requests objects (MDL_LOCK) on execution
  memory root in cases when we use stack TABLE_LIST objects to open
  tables. Got rid of redundant code by using unlock_locked_tables()
  function.
sql/sql_show.cc:
  Acquire shared metadata lock when we are getting information for
  I_S table directly from TABLE_SHARE without doing full-blown table
  open.  We use high priority lock request in this situation in
  order to avoid deadlocks.
  Also allocate metadata lock requests objects (MDL_LOCK) on
  execution memory root in cases when TABLE_LIST objects are also
  allocated there
sql/sql_table.cc:
  mysql_rm_table():
    Removed comment which is no longer relevant.
  mysql_rm_table_part2():
    Now caller of mysql_ha_rm_tables() should not own LOCK_open.
    Adjusted code to use new metadata locking subsystem instead of
    name-locks.
  lock_table_name_if_not_cached():
    Moved this function from sql_base.cc to this file and
    reimplemented it using metadata locking API.
  mysql_create_table():
    Adjusted code to use new MDL API.
  wait_while_table_is_used():
    Changed function to use new MDL subsystem. Made thread waiting
    in it killable (this also led to introduction of return value so
    caller can distinguish successful executions from situations
    when waiting was aborted).
  close_cached_tables():
    Thread waiting in this function is killable now. As result it
    has return value for distinguishing between succes and failure.
    Got rid of redundant boradcast_refresh() call.
  prepare_for_repair():
    Use MDL subsystem instead of name-locks.
  mysql_admin_table():
    mysql_ha_rm_tables() now always assumes that caller doesn't own
    LOCK_open.
  mysql_repair_table():
    We should mark all elements of table list as requiring
    upgradable metadata locks.
  mysql_create_table_like():
    Use new MDL subsystem instead of name-locks.
  create_temporary_tables():
    We don't need to obtain metadata locks when creating temporary
    table.
  mysql_fast_or_online_alter_table():
    Thread waiting in wait_while_table_is_used() is now killable.
  mysql_alter_table():
    Adjusted code to work with new MDL subsystem and to the fact
    that threads waiting in what_while_table_is_used() and
    close_cached_table() are now killable.
sql/sql_test.cc:
  We no longer have separate table cache. TABLE instances are now
  associated with/linked to TABLE_SHARE objects in table definition
  cache.
sql/sql_trigger.cc:
  Adjusted code to work with new metadata locking subsystem.  Also
  reopen_tables() no longer has mark_share_as_old argument (Instead
  of relying on this parameter and related behavior FLUSH TABLES
  WITH READ LOCK now takes global shared metadata lock).
sql/sql_udf.cc:
  Allocate metadata lock requests objects (MDL_LOCK) on execution
  memory root in cases when we use stack TABLE_LIST objects to open
  tables.
sql/sql_update.cc:
  Adjusted code to work with new meta-data locking subsystem.
sql/sql_view.cc:
  Added proper meta-data locking to implementations of
  CREATE/ALTER/DROP VIEW statements. Now we obtain exclusive
  meta-data lock on a view before creating/ changing/dropping it.
  This ensures that all concurrent statements that use this view
  will finish before our statement will proceed and therefore we
  will get correct order of statements in the binary log.
  Also ensure that TABLE_LIST::mdl_upgradable attribute is properly
  propagated for underlying tables of view.
sql/table.cc:
  Added auxiliary alloc_mdl_locks() function for allocating metadata
  lock request objects for all elements of table list.
sql/table.h:
  TABLE_SHARE:
    Got rid of unused members. Introduced members for storing lists
    of used and unused TABLE objects for this share.
  TABLE:
    Added members for linking TABLE objects into per-share lists of
    used and unused TABLE instances. Added member for holding
    pointer to metadata lock for this table.
  TABLE_LIST:
    Replaced boolean TABLE_LIST::create member with enum
    open_table_type member.  This allows easily handle situation in
    which instead of opening the table we want only to take
    exclusive meta-data lock on it (we need this in order to handle
    ALTER VIEW and CREATE VIEW statements).
    Introduced new mdl_upgradable member for marking elements of
    table list for which we need to take upgradable shared metadata
    lock instead of plain shared metadata lock.  Added pointer for
    holding pointer to MDL_LOCK for the table.
  Added auxiliary alloc_mdl_locks() function for allocating metadata
  lock requests objects for all elements of table list.  Added
  auxiliary set_all_mdl_upgradable() function for marking all
  elements in table list as requiring upgradable metadata locks.
storage/myisammrg/ha_myisammrg.cc:
  Allocate MDL_LOCK objects for underlying tables of MERGE table.
  To be reworked once Ingo pushes his patch for WL4144.
 2009-11-30 18:55:03 +03:00
Konstantin Osipov
69b9761f29 Initial import of WL#3726 "DDL locking for all metadata objects". 
Backport of:
------------------------------------------------------------
revno: 2630.4.1
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Fri 2008-05-23 17:54:03 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.
------------------------------------------------------------

This is the first patch in series. It transforms the metadata 
locking subsystem to use a dedicated module (mdl.h,cc). No 
significant changes in the locking protocol. 
The import passes the test suite with the exception of 
deprecated/removed 6.0 features, and MERGE tables. The latter
are subject to a fix by WL#4144.
Unfortunately, the original changeset comments got lost in a merge,
thus this import has its own (largely insufficient) comments.

This patch fixes Bug#25144 "replication / binlog with view breaks".
Warning: this patch introduces an incompatible change:
Under LOCK TABLES, it's no longer possible to FLUSH a table that 
was not locked for WRITE.
Under LOCK TABLES, it's no longer possible to DROP a table or
VIEW that was not locked for WRITE.

******
Backport of:
------------------------------------------------------------
revno: 2630.4.2
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 14:03:45 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  After review fixes in progress.

******
Backport of:
------------------------------------------------------------
revno: 2630.4.3
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 14:08:51 +0400
message:
  WL#3726 "DDL locking for all metadata objects"

  Fixed failing Windows builds by adding mdl.cc to the lists
  of files needed to build server/libmysqld on Windows.

******
Backport of:
------------------------------------------------------------
revno: 2630.4.4
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sat 2008-05-24 21:57:58 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  Fix for assert failures in kill.test which occured when one
  tried to kill ALTER TABLE statement on merge table while it
  was waiting in wait_while_table_is_used() for other connections
  to close this table.

  These assert failures stemmed from the fact that cleanup code
  in this case assumed that temporary table representing new
  version of table was open with adding to THD::temporary_tables
  list while code which were opening this temporary table wasn't
  always fulfilling this.

  This patch changes code that opens new version of table to
  always do this linking in. It also streamlines cleanup process
  for cases when error occurs while we have new version of table
  open.

******
WL#3726 "DDL locking for all metadata objects"
Add libmysqld/mdl.cc to .bzrignore.
******
Backport of:
------------------------------------------------------------
revno: 2630.4.6
committer: Dmitry Lenev <dlenev@mysql.com>
branch nick: mysql-6.0-3726-w
timestamp: Sun 2008-05-25 00:33:22 +0400
message:
  WL#3726 "DDL locking for all metadata objects".

  Addition to the fix of assert failures in kill.test caused by
  changes for this worklog.


Make sure we close the new table only once.
 2009-11-30 18:55:03 +03:00
Konstantin Osipov
bae0e81310 Backport of: 
-------------------------------------------------------------
revno: 2877
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: 35164-6.0
timestamp: Wed 2008-10-15 19:53:18 -0300
message:
Bug#35164: Large number of invalid pthread_attr_setschedparam calls
Bug#37536: Thread scheduling causes performance degradation at low thread count
Bug#12702: Long queries take 100% of CPU and freeze other applications under Windows

The problem is that although having threads with different priorities
yields marginal improvements [1] in some platforms [2], relying on some
statically defined priorities (QUERY_PRIOR and WAIT_PRIOR) to play well
(or to work at all) with different scheduling practices and disciplines
is, at best, a shot in the dark as the meaning of priority values may
change depending on the scheduling policy set for the process.

Another problem is that increasing priorities can hurt other concurrent
(running on the same hardware) applications (such as AMP) by causing
starvation problems as MySQL threads will successively preempt lower
priority processes. This can be evidenced by Bug#12702.

The solution is to not change the threads priorities and rely on the
system scheduler to perform its job. This also enables a system admin
to increase or decrease the scheduling priority of the MySQL process,
if intended.

Furthermore, the internal wrappers and code for changing the priority
of threads is being removed as they are now unused and ancient.

1. Due to unintentional side effects. On Solaris this could artificially
help benchmarks as calling the priority changing syscall millions of
times is more beneficial than the actual setting of the priority.

2. Where it actually works. It has never worked on Linux as the default
scheduling policy SCHED_OTHER only accepts the static priority 0.


configure.in:
  Remove checks for functions that are not used anymore.
include/config-netware.h:
  Remove unused define.
include/my_pthread.h:
  Remove thread priority changing wrappers.
mysys/my_pthread.c:
  Remove thread priority changing wrappers. They do not work properly
  and their implementations were incorrectly protected by a check for
  HAVE_PTHREAD_SETSCHEDPARAM.
mysys/thr_alarm.c:
  Remove meaningless (100) increase of a thread priority.
sql/mysql_priv.h:
  Remove meaningless thread priority values.
sql/mysqld.cc:
  Don't change thread priorities.
sql/slave.cc:
  Don't change thread priorities.
sql/slave.h:
  Update function prototype.
sql/sql_parse.cc:
  Don't change thread priorities.
sql/sql_prepare.cc:
  Don't change thread priorities.
sql/unireg.h:
  Mark flag as obsolete.
storage/innobase/handler/ha_innodb.cc:
  Remove use of obsolete flag and associated behavior.
storage/innobase/include/srv0srv.h:
  Remove use of obsolete flag and associated variables.
storage/innobase/os/os0thread.c:
  Remove use of obsolete flag and associated behavior.
storage/innobase/srv/srv0srv.c:
  Remove use of obsolete flag and associated variables.
 2009-11-23 19:57:31 +03:00
Konstantin Osipov
7edfae4e86 Backport of: 
-------------------------------------------------------------
revno: 2877
committer: Davi Arnaut <Davi.Arnaut@Sun.COM>
branch nick: 35164-6.0
timestamp: Wed 2008-10-15 19:53:18 -0300
message:
Bug#35164: Large number of invalid pthread_attr_setschedparam calls
Bug#37536: Thread scheduling causes performance degradation at low thread count
Bug#12702: Long queries take 100% of CPU and freeze other applications under Windows

The problem is that although having threads with different priorities
yields marginal improvements [1] in some platforms [2], relying on some
statically defined priorities (QUERY_PRIOR and WAIT_PRIOR) to play well
(or to work at all) with different scheduling practices and disciplines
is, at best, a shot in the dark as the meaning of priority values may
change depending on the scheduling policy set for the process.

Another problem is that increasing priorities can hurt other concurrent
(running on the same hardware) applications (such as AMP) by causing
starvation problems as MySQL threads will successively preempt lower
priority processes. This can be evidenced by Bug#12702.

The solution is to not change the threads priorities and rely on the
system scheduler to perform its job. This also enables a system admin
to increase or decrease the scheduling priority of the MySQL process,
if intended.

Furthermore, the internal wrappers and code for changing the priority
of threads is being removed as they are now unused and ancient.

1. Due to unintentional side effects. On Solaris this could artificially
help benchmarks as calling the priority changing syscall millions of
times is more beneficial than the actual setting of the priority.

2. Where it actually works. It has never worked on Linux as the default
scheduling policy SCHED_OTHER only accepts the static priority 0.
 2009-11-23 19:57:31 +03:00
unknown
a962160eec Merge with MySQL 5.1, with following additions: 
- Moved some code from innodb_plugin to xtradb, to ensure that all tests runs
- Did changes in pbxt and maria storage engines becasue of changes in thd->query
- Reverted wrong code in sql_table.cc for how ROW_FORMAT is used.

This is a re-commit of Monty's merge to eliminate an extra commit from
MySQL-5.1.42 that was accidentally included in the merge.

This is a merge of the MySQL 5.1.41 clone-off (clone-5.1.41-build). In
case there are any extra changes done before final MySQL 5.1.41
release, these will need to be merged later before MariaDB 5.1.41
release.
 2009-11-16 21:49:51 +01:00
Alexander Nozdrin
e6d79c2bc9 Auto-merge from mysql-trunk-merge. 2009-11-06 18:28:25 +03:00
Alexander Nozdrin
db6334d49e Auto-merge from mysql-trunk-merge. 2009-11-06 18:28:25 +03:00
Alexander Nozdrin
7cd11f45be Manual merge from mysql-trunk-merge. 2009-11-06 17:20:27 +03:00
Alexander Nozdrin
2ca5b2c791 Manual merge from mysql-trunk-merge. 2009-11-06 17:20:27 +03:00
Alexander Nozdrin
cd14c47c99 Manual merge from mysql-trunk-merge. 2009-11-05 23:28:35 +03:00
Alexander Nozdrin
f620cae974 Manual merge from mysql-trunk-merge. 2009-11-05 23:28:35 +03:00
Alexander Nozdrin
120425ccfd Fix automerge: use 'thd->query()' instead of 'thd->query'. 2009-11-05 17:51:00 +03:00
Alexander Nozdrin
3cf6345535 Fix automerge: use 'thd->query()' instead of 'thd->query'. 2009-11-05 17:51:00 +03:00