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Author SHA1 Message Date
Davi Arnaut
0d0b3f8aca Merge of mysql-5.1-bugteam into mysql-5.5-bugteam. 2010-11-16 07:45:07 -02:00
Davi Arnaut
2495e10c11 Merge of mysql-5.1-bugteam into mysql-5.5-bugteam. 2010-11-16 07:45:07 -02:00
Dmitry Lenev
6bf6272fda Patch that refactors global read lock implementation and fixes 
bug #57006 "Deadlock between HANDLER and FLUSH TABLES WITH READ
LOCK" and bug #54673 "It takes too long to get readlock for
'FLUSH TABLES WITH READ LOCK'".

The first bug manifested itself as a deadlock which occurred
when a connection, which had some table open through HANDLER
statement, tried to update some data through DML statement
while another connection tried to execute FLUSH TABLES WITH
READ LOCK concurrently.

What happened was that FTWRL in the second connection managed
to perform first step of GRL acquisition and thus blocked all
upcoming DML. After that it started to wait for table open
through HANDLER statement to be flushed. When the first connection
tried to execute DML it has started to wait for GRL/the second
connection creating deadlock.

The second bug manifested itself as starvation of FLUSH TABLES
WITH READ LOCK statements in cases when there was a constant
stream of concurrent DML statements (in two or more
connections).

This has happened because requests for protection against GRL
which were acquired by DML statements were ignoring presence of
pending GRL and thus the latter was starved.

This patch solves both these problems by re-implementing GRL
using metadata locks.

Similar to the old implementation acquisition of GRL in new
implementation is two-step. During the first step we block
all concurrent DML and DDL statements by acquiring global S
metadata lock (each DML and DDL statement acquires global IX
lock for its duration). During the second step we block commits
by acquiring global S lock in COMMIT namespace (commit code
acquires global IX lock in this namespace).

Note that unlike in old implementation acquisition of
protection against GRL in DML and DDL is semi-automatic.
We assume that any statement which should be blocked by GRL
will either open and acquires write-lock on tables or acquires
metadata locks on objects it is going to modify. For any such
statement global IX metadata lock is automatically acquired
for its duration.

The first problem is solved because waits for GRL become
visible to deadlock detector in metadata locking subsystem
and thus deadlocks like one in the first bug become impossible.

The second problem is solved because global S locks which
are used for GRL implementation are given preference over
IX locks which are acquired by concurrent DML (and we can
switch to fair scheduling in future if needed).

Important change:
FTWRL/GRL no longer blocks DML and DDL on temporary tables.
Before this patch behavior was not consistent in this respect:
in some cases DML/DDL statements on temporary tables were
blocked while in others they were not. Since the main use cases
for FTWRL are various forms of backups and temporary tables are
not preserved during backups we have opted for consistently
allowing DML/DDL on temporary tables during FTWRL/GRL.

Important change:
This patch changes thread state names which are used when
DML/DDL of FTWRL is waiting for global read lock. It is now
either "Waiting for global read lock" or "Waiting for commit
lock" depending on the stage on which FTWRL is.

Incompatible change:
To solve deadlock in events code which was exposed by this
patch we have to replace LOCK_event_metadata mutex with
metadata locks on events. As result we have to prohibit
DDL on events under LOCK TABLES.

This patch also adds extensive test coverage for interaction
of DML/DDL and FTWRL.

Performance of new and old global read lock implementations
in sysbench tests were compared. There were no significant
difference between new and old implementations.

mysql-test/include/check_ftwrl_compatible.inc:
  Added helper script which allows to check that a statement is
  compatible with FLUSH TABLES WITH READ LOCK.
mysql-test/include/check_ftwrl_incompatible.inc:
  Added helper script which allows to check that a statement is
  incompatible with FLUSH TABLES WITH READ LOCK.
mysql-test/include/handler.inc:
  Adjusted test case to the fact that now DROP TABLE closes
  open HANDLERs for the table to be dropped before checking
  if there active FTWRL in this connection.
mysql-test/include/wait_show_condition.inc:
  Fixed small error in the timeout message. The correct name
  of variable used as parameter for this script is "$condition"
  and not "$wait_condition".
mysql-test/r/delayed.result:
  Added test coverage for scenario which triggered assert in
  metadata locking subsystem.
mysql-test/r/events_2.result:
  Updated test results after prohibiting event DDL operations
  under LOCK TABLES.
mysql-test/r/flush.result:
  Added test coverage for bug #57006 "Deadlock between HANDLER
  and FLUSH TABLES WITH READ LOCK".
mysql-test/r/flush_read_lock.result:
  Added test coverage for various aspects of FLUSH TABLES WITH
  READ LOCK functionality.
mysql-test/r/flush_read_lock_kill.result:
  Adjusted test case after replacing custom global read lock
  implementation with one based on metadata locks. Use new
  debug_sync point. Do not disable concurrent inserts as now
  InnoDB we always use InnoDB table.
mysql-test/r/handler_innodb.result:
  Adjusted test case to the fact that now DROP TABLE closes
  open HANDLERs for the table to be dropped before checking
  if there active FTWRL in this connection.
mysql-test/r/handler_myisam.result:
  Adjusted test case to the fact that now DROP TABLE closes
  open HANDLERs for the table to be dropped before checking
  if there active FTWRL in this connection.
mysql-test/r/mdl_sync.result:
  Adjusted test case after replacing custom global read lock
  implementation with one based on metadata locks. Replaced
  usage of GRL-specific debug_sync's with appropriate sync
  points in MDL subsystem.
mysql-test/suite/perfschema/r/dml_setup_instruments.result:
  Updated test results after removing global
  COND_global_read_lock condition variable.
mysql-test/suite/perfschema/r/func_file_io.result:
  Ensure that this test doesn't affect subsequent tests.
  At the end of its execution enable back P_S instrumentation
  which this test disables at some point.
mysql-test/suite/perfschema/r/func_mutex.result:
  Ensure that this test doesn't affect subsequent tests.
  At the end of its execution enable back P_S instrumentation
  which this test disables at some point.
mysql-test/suite/perfschema/r/global_read_lock.result:
  Adjusted test case to take into account that new GRL
  implementation is based on MDL.
mysql-test/suite/perfschema/r/server_init.result:
  Adjusted test case after replacing custom global read
  lock implementation with one based on MDL and replacing
  LOCK_event_metadata mutex with metadata lock.
mysql-test/suite/perfschema/t/func_file_io.test:
  Ensure that this test doesn't affect subsequent tests.
  At the end of its execution enable back P_S instrumentation
  which this test disables at some point.
mysql-test/suite/perfschema/t/func_mutex.test:
  Ensure that this test doesn't affect subsequent tests.
  At the end of its execution enable back P_S instrumentation
  which this test disables at some point.
mysql-test/suite/perfschema/t/global_read_lock.test:
  Adjusted test case to take into account that new GRL
  implementation is based on MDL.
mysql-test/suite/perfschema/t/server_init.test:
  Adjusted test case after replacing custom global read
  lock implementation with one based on MDL and replacing
  LOCK_event_metadata mutex with metadata lock.
mysql-test/suite/rpl/r/rpl_tmp_table_and_DDL.result:
  Updated test results after prohibiting event DDL under
  LOCK TABLES.
mysql-test/t/delayed.test:
  Added test coverage for scenario which triggered assert in
  metadata locking subsystem.
mysql-test/t/events_2.test:
  Updated test case after prohibiting event DDL operations
  under LOCK TABLES.
mysql-test/t/flush.test:
  Added test coverage for bug #57006 "Deadlock between HANDLER
  and FLUSH TABLES WITH READ LOCK".
mysql-test/t/flush_block_commit.test:
  Adjusted test case after changing thread state name which
  is used when COMMIT waits for FLUSH TABLES WITH READ LOCK
  from "Waiting for release of readlock" to "Waiting for commit
  lock".
mysql-test/t/flush_block_commit_notembedded.test:
  Adjusted test case after changing thread state name which is
  used when DML waits for FLUSH TABLES WITH READ LOCK. Now we
  use "Waiting for global read lock" in this case.
mysql-test/t/flush_read_lock.test:
  Added test coverage for various aspects of FLUSH TABLES WITH
  READ LOCK functionality.
mysql-test/t/flush_read_lock_kill-master.opt:
  We no longer need to use make_global_read_lock_block_commit_loop
  debug tag in this test. Instead we rely on an appropriate
  debug_sync point in MDL code.
mysql-test/t/flush_read_lock_kill.test:
  Adjusted test case after replacing custom global read lock
  implementation with one based on metadata locks. Use new
  debug_sync point. Do not disable concurrent inserts as now
  InnoDB we always use InnoDB table.
mysql-test/t/lock_multi.test:
  Adjusted test case after changing thread state names which
  are used when DML or DDL waits for FLUSH TABLES WITH READ
  LOCK to "Waiting for global read lock".
mysql-test/t/mdl_sync.test:
  Adjusted test case after replacing custom global read lock
  implementation with one based on metadata locks. Replaced
  usage of GRL-specific debug_sync's with appropriate sync
  points in MDL subsystem. Updated thread state names which
  are used when DDL waits for FTWRL.
mysql-test/t/trigger_notembedded.test:
  Adjusted test case after changing thread state names which
  are used when DML or DDL waits for FLUSH TABLES WITH READ
  LOCK to "Waiting for global read lock".
sql/event_data_objects.cc:
  Removed Event_queue_element::status/last_executed_changed
  members and Event_queue_element::update_timing_fields()
  method. We no longer use this class for updating mysql.events
  once event is chosen for execution. Accesses to instances of
  this class in scheduler thread require protection by
  Event_queue::LOCK_event_queue mutex and we try to avoid
  updating table while holding this lock.
sql/event_data_objects.h:
  Removed Event_queue_element::status/last_executed_changed
  members and Event_queue_element::update_timing_fields()
  method. We no longer use this class for updating mysql.events
  once event is chosen for execution. Accesses to instances of
  this class in scheduler thread require protection by
  Event_queue::LOCK_event_queue mutex and we try to avoid
  updating table while holding this lock.
sql/event_db_repository.cc:
  - Changed Event_db_repository methods to not release all
    metadata locks once they are done updating mysql.events
    table. This allows to keep metadata lock protecting
    against GRL and lock protecting particular event around
    until corresponding DDL statement is written to the binary
    log.
  - Removed logic for conditional update of "status" and
    "last_executed" fields from update_timing_fields_for_event()
    method. In the only case when this method is called now
    "last_executed" is always modified and tracking change
    of "status" is too much hassle.
sql/event_db_repository.h:
  Removed logic for conditional update of "status" and
  "last_executed" fields from Event_db_repository::
  update_timing_fields_for_event() method.
  In the only case when this method is called now "last_executed"
  is always modified and tracking change of "status" field is
  too much hassle.
sql/event_queue.cc:
  Changed event scheduler code not to update mysql.events
  table while holding Event_queue::LOCK_event_queue mutex.
  Doing so led to a deadlock with a new GRL implementation.
  This deadlock didn't occur with old implementation due to
  fact that code acquiring protection against GRL ignored
  pending GRL requests (which lead to GRL starvation).
  One of goals of new implementation is to disallow GRL
  starvation and so we have to solve problem with this
  deadlock in a different way.
sql/events.cc:
  Changed methods of Events class to acquire protection
  against GRL while perfoming DDL statement and keep it
  until statement is written to the binary log.
  Unfortunately this step together with new GRL implementation
  exposed deadlock involving Events::LOCK_event_metadata
  and GRL. To solve it Events::LOCK_event_metadata mutex was
  replaced with a metadata lock on event. As a side-effect
  events DDL has to be prohibited under LOCK TABLES even in
  cases when mysql.events table was explicitly locked for
  write.
sql/events.h:
  Replaced Events::LOCK_event_metadata mutex with a metadata
  lock on event.
sql/ha_ndbcluster.cc:
  Updated code after replacing custom global read lock
  implementation with one based on MDL. Since MDL subsystem
  should now be able to detect deadlocks involving metadata
  locks and GRL there is no need for special handling of
  active GRL.
sql/handler.cc:
  Replaced custom implementation of global read lock with
  one based on metadata locks. Consequently when doing
  commit instead of calling method of Global_read_lock
  class to acquire protection against GRL we simply acquire
  IX in COMMIT namespace.
sql/lock.cc:
  Replaced custom implementation of global read lock with
  one based on metadata locks. This step allows to expose
  wait for GRL to deadlock detector of MDL subsystem and
  thus succesfully resolve deadlocks similar to one behind
  bug #57006 "Deadlock between HANDLER and FLUSH TABLES
  WITH READ LOCK". It also solves problem with GRL starvation
  described in bug #54673 "It takes too long to get readlock
  for 'FLUSH TABLES WITH READ LOCK'" since metadata locks used
  by GRL give preference to FTWRL statement instead of DML
  statements (if needed in future this can be changed to
  fair scheduling).
  
  Similar to old implementation of acquisition of GRL is
  two-step. During the first step we block all concurrent
  DML and DDL statements by acquiring global S metadata lock
  (each DML and DDL statement acquires global IX lock for
  its duration). During the second step we block commits by
  acquiring global S lock in COMMIT namespace (commit code
  acquires global IX lock in this namespace).
  
  Note that unlike in old implementation acquisition of
  protection against GRL in DML and DDL is semi-automatic.
  We assume that any statement which should be blocked by GRL
  will either open and acquires write-lock on tables or acquires
  metadata locks on objects it is going to modify. For any such
  statement global IX metadata lock is automatically acquired
  for its duration.
  
  To support this change:
  - Global_read_lock::lock/unlock_global_read_lock and
    make_global_read_lock_block_commit methods were changed
    accordingly.
  - Global_read_lock::wait_if_global_read_lock() and
    start_waiting_global_read_lock() methods were dropped.
    It is now responsibility of code acquiring metadata locks
    opening tables to acquire protection against GRL by
    explicitly taking global IX lock with statement duration.
  - Global variables, mutex and condition variable used by
    old implementation was removed.
  - lock_routine_name() was changed to use statement duration for
    its global IX lock. It was also renamed to lock_object_name()
    as it now also used to take metadata locks on events.
  - Global_read_lock::set_explicit_lock_duration() was added which
    allows not to release locks used for GRL when leaving prelocked
    mode.
sql/lock.h:
  - Renamed lock_routine_name() to lock_object_name() and changed
    its signature to allow its usage for events.
  - Removed broadcast_refresh() function. It is no longer needed
    with new GRL implementation.
sql/log_event.cc:
  Release metadata locks with statement duration at the end
  of processing legacy event for LOAD DATA. This ensures that
  replication thread processing such event properly releases
  its protection against global read lock.
sql/mdl.cc:
  Changed MDL subsystem to support new MDL-based implementation
  of global read lock.
  
  Added COMMIT and EVENTS namespaces for metadata locks. Changed
  thread state name for GLOBAL namespace to "Waiting for global
  read lock".
  
  Optimized MDL_map::find_or_insert() method to avoid taking
  m_mutex mutex when looking up MDL_lock objects for GLOBAL
  or COMMIT namespaces. We keep pre-created MDL_lock objects
  for these namespaces around and simply return pointers to
  these global objects when needed.
  
  Changed MDL_lock/MDL_scoped_lock to properly handle
  notification of insert delayed handler threads when FTWRL
  takes global S lock.
  
  Introduced concept of lock duration. In addition to locks with
  transaction duration which work in the way which is similar to
  how locks worked before (i.e. they are released at the end of
  transaction), locks with statement and explicit duration were
  introduced.
  Locks with statement duration are automatically released at the
  end of statement. Locks with explicit duration require explicit
  release and obsolete concept of transactional sentinel.
  
  * Changed MDL_request and MDL_ticket classes to support notion
    of duration.
  * Changed MDL_context to keep locks with different duration in
    different lists. Changed code handling ticket list to take
    this into account.
  * Changed methods responsible for releasing locks to take into
    account duration of tickets. Particularly public
    MDL_context::release_lock() method now only can release
    tickets with explicit duration (there is still internal
    method which allows to specify duration). To release locks
    with statement or transaction duration one have to use
    release_statement/transactional_locks() methods.
  * Concept of savepoint for MDL subsystem now has to take into
    account locks with statement duration. Consequently
    MDL_savepoint class was introduced and methods working with
    savepoints were updated accordingly.
  * Added methods which allow to set duration for one or all
    locks in the context.
sql/mdl.h:
  Changed MDL subsystem to support new MDL-based implementation
  of global read lock.
  
  Added COMMIT and EVENTS namespaces for metadata locks.
  
  Introduced concept of lock duration. In addition to locks with
  transaction duration which work in the way which is similar to
  how locks worked before (i.e. they are released at the end of
  transaction), locks with statement and explicit duration were
  introduced.
  Locks with statement duration are automatically released at the
  end of statement. Locks with explicit duration require explicit
  release and obsolete concept of transactional sentinel.
  
  * Changed MDL_request and MDL_ticket classes to support notion
    of duration.
  * Changed MDL_context to keep locks with different duration in
    different lists. Changed code handling ticket list to take
    this into account.
  * Changed methods responsible for releasing locks to take into
    account duration of tickets. Particularly public
    MDL_context::release_lock() method now only can release
    tickets with explicit duration (there is still internal
    method which allows to specify duration). To release locks
    with statement or transaction duration one have to use
    release_statement/transactional_locks() methods.
  * Concept of savepoint for MDL subsystem now has to take into
    account locks with statement duration. Consequently
    MDL_savepoint class was introduced and methods working with
    savepoints were updated accordingly.
  * Added methods which allow to set duration for one or all
    locks in the context.
sql/mysqld.cc:
  Removed global mutex and condition variables which were used
  by old implementation of GRL.
  Also we no longer need to initialize Events::LOCK_event_metadata
  mutex as it was replaced with metadata locks on events.
sql/mysqld.h:
  Removed global variable, mutex and condition variables which
  were used by old implementation of GRL.
sql/rpl_rli.cc:
  When slave thread closes tables which were open for handling
  of RBR events ensure that it releases global IX lock which
  was acquired as protection against GRL.
sql/sp.cc:
  Adjusted code to the new signature of lock_object/routine_name(),
  to the fact that one now needs specify duration of lock when
  initializing MDL_request and to the fact that savepoints for MDL
  subsystem are now represented by MDL_savepoint class.
sql/sp_head.cc:
  Ensure that statements in stored procedures release statement
  metadata locks and thus release their protectiong against GRL
  in proper moment in time.
  Adjusted code to the fact that one now needs specify duration
  of lock when initializing MDL_request.
sql/sql_admin.cc:
  Adjusted code to the fact that one now needs specify duration
  of lock when initializing MDL_request.
sql/sql_base.cc:
  - Implemented support for new approach to acquiring protection
    against global read lock. We no longer acquire such protection
    explicitly on the basis of statement flags. Instead we always
    rely on code which is responsible for acquiring metadata locks
    on object to be changed acquiring this protection. This is
    achieved by acquiring global IX metadata lock with statement
    duration. Code doing this also responsible for checking that
    current connection has no active GRL by calling an
    Global_read_lock::can_acquire_protection() method.
    Changed code in open_table() and lock_table_names()
    accordingly.
    Note that as result of this change DDL and DML on temporary
    tables is always compatible with GRL (before it was
    incompatible in some cases and compatible in other cases).
  - To speed-up code acquiring protection against GRL introduced
    m_has_protection_against_grl member in Open_table_context
    class. It indicates that protection was already acquired
    sometime during open_tables() execution and new attempts
    can be skipped.
  - Thanks to new GRL implementation calls to broadcast_refresh()
    became unnecessary and were removed.
  - Adjusted code to the fact that one now needs specify duration
    of lock when initializing MDL_request and to the fact that
    savepoints for MDL subsystem are now represented by
    MDL_savepoint class.
sql/sql_base.h:
  Adjusted code to the fact that savepoints for MDL subsystem are
  now represented by MDL_savepoint class.
  Also introduced Open_table_context::m_has_protection_against_grl
  member which allows to avoid acquiring protection against GRL
  while opening tables if such protection was already acquired.
sql/sql_class.cc:
  Changed THD::leave_locked_tables_mode() after transactional
  sentinel for metadata locks was obsoleted by introduction of
  locks with explicit duration.
sql/sql_class.h:
  - Adjusted code to the fact that savepoints for MDL subsystem
    are now represented by MDL_savepoint class.
  - Changed Global_read_lock class according to changes in
    global read lock implementation:
    * wait_if_global_read_lock and start_waiting_global_read_lock
      are now gone. Instead code needing protection against GRL
      has to acquire global IX metadata lock with statement
      duration itself. To help it new can_acquire_protection()
      was introduced. Also as result of the above change
      m_protection_count member is gone too.
    * Added m_mdl_blocks_commits_lock member to store metadata
      lock blocking commits.
    * Adjusted code to the fact that concept of transactional
      sentinel was obsoleted by concept of lock duration.
  - Removed CF_PROTECT_AGAINST_GRL flag as it is no longer
    necessary. New GRL implementation acquires protection
    against global read lock automagically when statement
    acquires metadata locks on tables or other objects it
    is going to change.
sql/sql_db.cc:
  Adjusted code to the fact that one now needs specify duration
  of lock when initializing MDL_request.
sql/sql_handler.cc:
  Removed call to broadcast_refresh() function. It is no longer
  needed with new GRL implementation.
  Adjusted code after introducing duration concept for metadata
  locks. Particularly to the fact transactional sentinel was
  replaced with explicit duration.
sql/sql_handler.h:
  Renamed mysql_ha_move_tickets_after_trans_sentinel() to
  mysql_ha_set_explicit_lock_duration() after transactional
  sentinel was obsoleted by locks with explicit duration.
sql/sql_insert.cc:
  Adjusted code handling delaying inserts after switching to
  new GRL implementation. Now connection thread initiating
  delayed insert has to acquire global IX lock in addition
  to metadata lock on table being inserted into. This IX lock
  protects against GRL and similarly to SW lock on table being
  inserted into has to be passed to handler thread in order to
  avoid deadlocks.
sql/sql_lex.cc:
  LEX::protect_against_global_read_lock member is no longer
  necessary since protection against GRL is automatically
  taken by code acquiring metadata locks/opening tables.
sql/sql_lex.h:
  LEX::protect_against_global_read_lock member is no longer
  necessary since protection against GRL is automatically
  taken by code acquiring metadata locks/opening tables.
sql/sql_parse.cc:
  - Implemented support for new approach to acquiring protection
    against global read lock. We no longer acquire such protection
    explicitly on the basis of statement flags. Instead we always
    rely on code which is responsible for acquiring metadata locks
    on object to be changed acquiring this protection. This is
    achieved by acquiring global IX metadata lock with statement
    duration. This lock is automatically released at the end of
    statement execution.
  - Changed implementation of CREATE/DROP PROCEDURE/FUNCTION not
    to release metadata locks and thus protection against of GRL
    in the middle of statement execution.
  - Adjusted code to the fact that one now needs specify duration
    of lock when initializing MDL_request and to the fact that
    savepoints for MDL subsystem are now represented by
    MDL_savepoint class.
sql/sql_prepare.cc:
  Adjusted code to the to the fact that savepoints for MDL
  subsystem are now represented by MDL_savepoint class.
sql/sql_rename.cc:
  With new GRL implementation there is no need to explicitly
  acquire protection against GRL before renaming tables.
  This happens automatically in code which acquires metadata
  locks on tables being renamed.
sql/sql_show.cc:
  Adjusted code to the fact that one now needs specify duration
  of lock when initializing MDL_request and to the fact that
  savepoints for MDL subsystem are now represented by
  MDL_savepoint class.
sql/sql_table.cc:
  - With new GRL implementation there is no need to explicitly
    acquire protection against GRL before dropping tables.
    This happens automatically in code which acquires metadata
    locks on tables being dropped.
  - Changed mysql_alter_table() not to release lock on new table
    name explicitly and to rely on automatic release of locks
    at the end of statement instead. This was necessary since
    now MDL_context::release_lock() is supported only for locks
    for explicit duration.
sql/sql_trigger.cc:
  With new GRL implementation there is no need to explicitly
  acquire protection against GRL before changing table triggers.
  This happens automatically in code which acquires metadata
  locks on tables which triggers are to be changed.
sql/sql_update.cc:
  Fix bug exposed by GRL testing. During prepare phase acquire
  only S metadata locks instead of SW locks to keep prepare of
  multi-UPDATE compatible with concurrent LOCK TABLES WRITE
  and global read lock.
sql/sql_view.cc:
  With new GRL implementation there is no need to explicitly
  acquire protection against GRL before creating view.
  This happens automatically in code which acquires metadata
  lock on view to be created.
sql/sql_yacc.yy:
  LEX::protect_against_global_read_lock member is no longer
  necessary since protection against GRL is automatically
  taken by code acquiring metadata locks/opening tables.
sql/table.cc:
  Adjusted code to the fact that one now needs specify duration
  of lock when initializing MDL_request.
sql/table.h:
  Adjusted code to the fact that one now needs specify duration
  of lock when initializing MDL_request.
sql/transaction.cc:
  Replaced custom implementation of global read lock with
  one based on metadata locks. Consequently when doing
  commit instead of calling method of Global_read_lock
  class to acquire protection against GRL we simply acquire
  IX in COMMIT namespace.
  Also adjusted code to the fact that MDL savepoint is now
  represented by MDL_savepoint class.
 2010-11-11 20:11:05 +03:00
Dmitry Lenev
378cdc58c1 Patch that refactors global read lock implementation and fixes 
bug #57006 "Deadlock between HANDLER and FLUSH TABLES WITH READ
LOCK" and bug #54673 "It takes too long to get readlock for
'FLUSH TABLES WITH READ LOCK'".

The first bug manifested itself as a deadlock which occurred
when a connection, which had some table open through HANDLER
statement, tried to update some data through DML statement
while another connection tried to execute FLUSH TABLES WITH
READ LOCK concurrently.

What happened was that FTWRL in the second connection managed
to perform first step of GRL acquisition and thus blocked all
upcoming DML. After that it started to wait for table open
through HANDLER statement to be flushed. When the first connection
tried to execute DML it has started to wait for GRL/the second
connection creating deadlock.

The second bug manifested itself as starvation of FLUSH TABLES
WITH READ LOCK statements in cases when there was a constant
stream of concurrent DML statements (in two or more
connections).

This has happened because requests for protection against GRL
which were acquired by DML statements were ignoring presence of
pending GRL and thus the latter was starved.

This patch solves both these problems by re-implementing GRL
using metadata locks.

Similar to the old implementation acquisition of GRL in new
implementation is two-step. During the first step we block
all concurrent DML and DDL statements by acquiring global S
metadata lock (each DML and DDL statement acquires global IX
lock for its duration). During the second step we block commits
by acquiring global S lock in COMMIT namespace (commit code
acquires global IX lock in this namespace).

Note that unlike in old implementation acquisition of
protection against GRL in DML and DDL is semi-automatic.
We assume that any statement which should be blocked by GRL
will either open and acquires write-lock on tables or acquires
metadata locks on objects it is going to modify. For any such
statement global IX metadata lock is automatically acquired
for its duration.

The first problem is solved because waits for GRL become
visible to deadlock detector in metadata locking subsystem
and thus deadlocks like one in the first bug become impossible.

The second problem is solved because global S locks which
are used for GRL implementation are given preference over
IX locks which are acquired by concurrent DML (and we can
switch to fair scheduling in future if needed).

Important change:
FTWRL/GRL no longer blocks DML and DDL on temporary tables.
Before this patch behavior was not consistent in this respect:
in some cases DML/DDL statements on temporary tables were
blocked while in others they were not. Since the main use cases
for FTWRL are various forms of backups and temporary tables are
not preserved during backups we have opted for consistently
allowing DML/DDL on temporary tables during FTWRL/GRL.

Important change:
This patch changes thread state names which are used when
DML/DDL of FTWRL is waiting for global read lock. It is now
either "Waiting for global read lock" or "Waiting for commit
lock" depending on the stage on which FTWRL is.

Incompatible change:
To solve deadlock in events code which was exposed by this
patch we have to replace LOCK_event_metadata mutex with
metadata locks on events. As result we have to prohibit
DDL on events under LOCK TABLES.

This patch also adds extensive test coverage for interaction
of DML/DDL and FTWRL.

Performance of new and old global read lock implementations
in sysbench tests were compared. There were no significant
difference between new and old implementations.
 2010-11-11 20:11:05 +03:00
Davi Arnaut
cd1c6e220d Bug#58057: 5.1 libmysql/libmysql.c unused variable/compile failure 
Bug#57995: Compiler flag change build error on OSX 10.4: my_getncpus.c
Bug#57996: Compiler flag change build error on OSX 10.5 : bind.c
Bug#57994: Compiler flag change build error : my_redel.c
Bug#57993: Compiler flag change build error on FreeBsd 7.0 : regexec.c
Bug#57992: Compiler flag change build error on FreeBsd : mf_keycache.c
Bug#57997: Compiler flag change build error on OSX 10.6: debug_sync.cc

Fix assorted compiler generated warnings.

cmd-line-utils/readline/bind.c:
  Bug#57996: Compiler flag change build error on OSX 10.5 : bind.c
  
  Initialize variable to work around a false positive warning.
include/m_string.h:
  Bug#57994: Compiler flag change build error : my_redel.c
  
  The expansion of stpcpy (in glibc) causes warnings if the
  return value of strmov is not being used. Since stpcpy is
  a GNU extension and the expansion ends up using a built-in
  provided by GCC, use the compiler provided built-in directly
  when possible.
include/my_compiler.h:
  Define a dummy MY_GNUC_PREREQ when not compiling with GCC.
libmysql/libmysql.c:
  Bug#58057: 5.1 libmysql/libmysql.c unused variable/compile failure
  
  Variable might not be used in some cases. So, tag it as unused.
mysys/mf_keycache.c:
  Bug#57992: Compiler flag change build error on FreeBsd : mf_keycache.c
  
  Use UNINIT_VAR to work around a false positive warning.
mysys/my_getncpus.c:
  Bug#57995: Compiler flag change build error on OSX 10.4: my_getncpus.c
  
  Declare variable in the same block where it is used.
regex/regexec.c:
  Bug#57993: Compiler flag change build error on FreeBsd 7.0 : regexec.c
  
  Work around a compiler bug which causes the cast to not be enforced.
sql/debug_sync.cc:
  Bug#57997: Compiler flag change build error on OSX 10.6: debug_sync.cc
  
  Use UNINIT_VAR to work around a false positive warning.
sql/handler.cc:
  Use UNINIT_VAR to work around a false positive warning.
sql/slave.cc:
  Use UNINIT_VAR to work around a false positive warning.
sql/sql_partition.cc:
  Use UNINIT_VAR to work around a false positive warning.
storage/myisam/ft_nlq_search.c:
  Use UNINIT_VAR to work around a false positive warning.
storage/myisam/mi_create.c:
  Use UNINIT_VAR to work around a false positive warning.
storage/myisammrg/myrg_open.c:
  Use UNINIT_VAR to work around a false positive warning.
tests/mysql_client_test.c:
  Change function to take a pointer to const, no need for a cast.
 2010-11-10 19:14:47 -02:00
Davi Arnaut
80246ac8b8 Bug#58057: 5.1 libmysql/libmysql.c unused variable/compile failure 
Bug#57995: Compiler flag change build error on OSX 10.4: my_getncpus.c
Bug#57996: Compiler flag change build error on OSX 10.5 : bind.c
Bug#57994: Compiler flag change build error : my_redel.c
Bug#57993: Compiler flag change build error on FreeBsd 7.0 : regexec.c
Bug#57992: Compiler flag change build error on FreeBsd : mf_keycache.c
Bug#57997: Compiler flag change build error on OSX 10.6: debug_sync.cc

Fix assorted compiler generated warnings.
 2010-11-10 19:14:47 -02:00
Michael Widenius
9d68ccdeb8 Added option BACKUP_ALL to mysqld --myisam-recover to also get a backup of the index file before it's repaired. 
Removed wrong call to translog_buffer_unlock() that caused 'unlocking not locked mutex' failure in Aria log handler.

extra/replace.c:
  Updated call to my_redel()
include/maria.h:
  Updated prototype for maria_change_to_newfile
include/my_sys.h:
  Updated prototypes
  Added my_create_backup_name
include/myisam.h:
  Updated prototypes
include/myisamchk.h:
  Added 'backup_time' to st_handler_check_param to be able to generate same name for backuped data and index file
mysys/my_redel.c:
  Added time_t option to my_redel() to be able to generate same backup extensions for many files
sql/handler.cc:
  Added start_time to st_ha_check_opt
sql/handler.h:
  Added start_time to HA_CHECK_OPT
sql/mysqld.cc:
  Added option BACKUP_ALL to --myisam-recover
storage/maria/ha_maria.cc:
  Remember start time for repair
storage/maria/ma_check.c:
  Use remembered start time for backup file names
  Removed some dead code
storage/maria/ma_loghandler.c:
  Removed wrong call to translog_buffer_unlock() that caused 'unlocking not locked mutex' failure in log handler.
storage/maria/maria_chk.c:
  Removed dead code (O_NEW_INDEX was never set)
  Report if table was 'crashed on repair'
storage/maria/maria_pack.c:
  Updated parameters to my_redel()
storage/myisam/ha_myisam.cc:
  Added recover option BACKUP_ALL to get a backup of the index file before it's repaired.
  Print information to log if we make a backup of data as part of repair.
storage/myisam/ha_myisam.h:
  Added HA_RECOVER_FULL_BACKUP
storage/myisam/mi_check.c:
  Use remembered start time for backup file names
  Added mi_make_backup_of_index()
storage/myisam/myisamchk.c:
  Removed dead code (O_NEW_INDEX was never set)
  Report if table was 'crashed on repair'
storage/myisam/myisampack.c:
  Updated call to my_redel()
 2010-11-07 14:25:29 +02:00
Michael Widenius
c670b9021e Automerge with 5.2 2010-11-05 12:37:51 +02:00
Michael Widenius
7647c2744c Automatic merge with MariaDB 5.1 2010-11-04 17:08:28 +02:00
Michael Widenius
3797ca41b3 Automatic merge with 5.1 2010-11-04 16:53:10 +02:00
unknown
e55c4836a1 MBug#643463: slow XtraDB shutdown due to 10 second sleep in purge thread 
Implement os_event_wait_time() for POSIX systems.

In the purge thread, use os_event_wait_time() when sleeping rather than sleep,
and signal the event when server shuts down, so we do not need to wait for
upto 10 seconds until the purge thread wakes up.

Also fix bug that warnings that were pushed after we call set_ok_status() were
not included in the waning count sent to the client in the result packet.

Also in mysqltest, in recursive die() invocation at least print the message
before aborting.

client/mysqltest.cc:
  If we detect recursive die(), at least print the message before aborting.
mysql-test/r/warnings_debug.result:
  Test case.
mysql-test/t/warnings_debug.test:
  Test case.
sql/handler.cc:
  Force generation of a warning with specific debug option, for testing.
sql/protocol.cc:
  Fix wrong DBUG_ENTER
sql/sql_class.h:
  Add method to count warnings pushed after set_ok_status() is called.
sql/sql_error.cc:
  Also count warnings pushed after set_ok_status() is called.
storage/xtradb/include/os0sync.h:
  Implement working os_sync_wait_time() for POSIX.
storage/xtradb/include/srv0srv.h:
  Make the purge thread wait for an event when sleeping, so we can signal it to
  wakeup immediately at shutdown.
storage/xtradb/log/log0log.c:
  Make the purge thread wait for an event when sleeping, so we can signal it to
  wakeup immediately at shutdown.
storage/xtradb/os/os0sync.c:
  Implement working os_sync_wait_time() for POSIX.
storage/xtradb/srv/srv0srv.c:
  Make the purge thread wait for an event when sleeping, so we can signal it to
  wakeup immediately at shutdown.
 2010-11-03 22:40:53 +01:00
Michael Widenius
20acfbf30d Fix for: LP #634955: Assert in _ma_update_at_original_place() 
Added locking of lock mutex when updating status in external_unlock() for Aria and MyISAM tables.
Fixed that 'source' command doesn't cause mysql command line tool to exit on error.
DEBUG_EXECUTE() and DEBUG_EVALUATE_IF() should not execute things based on wildcards. (Allows one to run --debug with mysql-test-run scripts that uses @debug)
Fixed several core dump, deadlock and crashed table bugs in handling of LOCK TABLE with MERGE tables:
- Added priority of locks to avoid crashes with MERGE tables.
- Added thr_lock_merge() to allow one to merge two results of thr_lock().
Fixed 'not found row' bug in REPLACE with Aria tables.
Mark MyISAM tables that are part of MERGE with HA_OPEN_MERGE_TABLE and set the locks to have priority THR_LOCK_MERGE_PRIV.
- By sorting MERGE tables last in thr_multi_unlock() it's safer to release and relock them many times (can happen when TRIGGERS are created)
Avoid printing (null) in debug file (to easier find out wrong NULL pointer usage with %s).



client/mysql.cc:
  Fixed that 'source' command doesn't cause mysql command line tool to exit on error.
client/mysqltest.cc:
  Don't send NULL to fn_format(). (Can cause crash on Solaris when using --debug)
dbug/dbug.c:
  DEBUG_EXECUTE() and DEBUG_EVALUATE_IF() should not execute things based on wildcards.
include/my_base.h:
  Added flag to signal if one opens a MERGE table.
  Added extra() command to signal that one is not part of a MERGE table anymore.
include/thr_lock.h:
  Added priority for locks (needed to fix bug in thr_lock when using MERGE tables)
  Added option to thr_unlock() if get_status() should be called.
  Added prototype for thr_merge_locks().
mysql-test/mysql-test-run.pl:
  Ignore crashed table warnings for tables named 'crashed'.
mysql-test/r/merge.result:
  Renamed triggers to make debugging easier.
  Added some CHECK TABLES to catch errors earlier.
  Additional tests.
mysql-test/r/merge_debug.result:
  Test of error handling when reopening MERGE tables.
mysql-test/r/udf_query_cache.result:
  Added missing flush status
mysql-test/suite/parts/r/partition_repair_myisam.result:
  Update results
mysql-test/t/merge.test:
  Renamed triggers to make debugging easier.
  Added some CHECK TABLES to catch errors earlier.
  Additional tests.
mysql-test/t/merge_debug.test:
  Test of error handling when reopening MERGE tables.
mysql-test/t/udf_query_cache.test:
  Added missing flush status
mysys/my_getopt.c:
  Removed not used variable
mysys/my_symlink2.c:
  Changed (null) to (NULL) to make it easier to find NULL arguments to DBUG_PRINT() functions.
  (On linux, NULL to sprintf is printed 'null')
mysys/thr_lock.c:
  Added priority of locks to avoid crashes with MERGE tables.
  Added thr_lock_merge() to allow one to merge two results of thr_lock().
  - This is needed for MyISAM as all locked table must share the same status. If not, you will not see newly inserted rows in other instances of the table.
  If calling thr_unlock() with THR_UNLOCK_UPDATE_STATUS, call update_status() and restore_status() for the locks. This is needed in some rare cases where we call thr_unlock() followed by thr_lock() without calling external_unlock/external_lock in between.
  Simplify loop in thr_multi_lock().
  Added 'start_trans', which is called at end of thr_multi_lock() when all locks are taken.
  - This was needed by Aria to ensure that transaction is started when we got all locks, not at get_status(). Without this, some rows could not be visible when we lock two tables at the same time, causing REPLACE using two tables to fail unexpectedly.
sql/handler.cc:
  Add an assert() in handler::print_error() for "impossible errors" (like table is crashed) when --debug-assert-if-crashed-table is used.
sql/lock.cc:
  Simplify mysql_lock_tables() code if get_lock_data() returns 0 locks.
  Added new parameter to thr_multi_unlock()
  In mysql_unlock_read_tables(), call first externa_unlock(), then thr_multi_unlock();  This is same order as we do in mysql_unlock_tables().
  Don't abort locks in mysql_lock_abort() for merged tables when a MERGE table is deleted; Would cause a spin lock.
  Added call to thr_merge_locks() in mysql_lock_merge() to ensure consistency in thr_locks().
  - New locks of same type and table is stored after the old lock to ensure that we get the status from the original lock.
sql/mysql_priv.h:
  Added debug_assert_if_crashed_table
sql/mysqld.cc:
  Added --debug-assert-if-crashed-table
sql/parse_file.cc:
  Don't print '(null)' in DBUG_PRINT of no dir given
sql/set_var.cc:
  Increase default size of buffer for @debug variable.
sql/sql_base.cc:
  In case of error from reopen_table() in reopen_tables(), call unlock_open_table() and restart loop.
  - This fixed bug when we twice deleted same table from open_cache.
  Don't take name lock for already name locked table in open_unireg_entry().
  - Fixed bug when doing repair in reopen_table().
  - In detach_merge_children(), always detach if 'clear_refs' is given. We can't trust parent->children_attached as this function can be called twice, first time with clear_refs set to 0.
sql/sql_class.cc:
  Changed printing of (null) to "" in set_thd_proc_info()
sql/sql_parse.cc:
  Added DBUG
sql/sql_trigger.cc:
  Don't call unlink_open_table() if reopen_table() fails as the table may already be freed.
storage/maria/ma_bitmap.c:
  Fixed DBUG_ASSERT() in allocate_tail()
storage/maria/ma_blockrec.c:
  Fixed wrong calculation of row length for very small rows in undo_row_update().
  - Fixes ASSERT() when doing undo.
storage/maria/ma_blockrec.h:
  Added _ma_block_start_trans() and _ma_block_start_trans_no_versioning()
storage/maria/ma_locking.c:
  Call _ma_update_status_with_lock() when releasing write locks.
  - Fixes potential problem with updating status without the proper lock.
storage/maria/ma_open.c:
  Changed to use start_trans() instead of get_status() to ensure that we see all rows in all locked tables when we got the locks.
  - Fixed 'not found row' bug in REPLACE with Aria tables.
storage/maria/ma_state.c:
  Added _ma_update_status_with_lock() and _ma_block_start_trans().
  This is to ensure that we see all rows in all locked tables when we got the locks.
storage/maria/ma_state.h:
  Added _ma_update_status_with_lock()
storage/maria/ma_write.c:
  More DBUG_PRINT
storage/myisam/mi_check.c:
  Fixed error message
storage/myisam/mi_extra.c:
  Added HA_EXTRA_DETACH_CHILD:
  - Detach MyISAM table to not be part of MERGE table (remove flag & lock priority).
storage/myisam/mi_locking.c:
  Call mi_update_status_with_lock() when releasing write locks.
  - Fixes potential problem with updating status without the proper lock.
  Change to use new HA_OPEN_MERGE_TABLE flag to test if MERGE table.
  Added mi_fix_status(), called by thr_merge().
storage/myisam/mi_open.c:
  Added marker if part of MERGE table.
  Call mi_fix_status() in thr_lock() for transactional tables.
storage/myisam/myisamdef.h:
  Change my_once_flag to uint, as it stored different values than just 0/1
  Added 'open_flag' to store state given to mi_open()
storage/myisammrg/ha_myisammrg.cc:
  Add THR_LOCK_MERGE_PRIV to THR_LOCK_DATA to get MERGE locks sorted after other types of locks.
storage/myisammrg/myrg_locking.c:
  Remove windows specific code.
storage/myisammrg/myrg_open.c:
  Use HA_OPEN_MERGE_TABLE to mi_open().
  Set HA_OPEN_MERGE_TABLE for linked MyISAM tables.
storage/xtradb/buf/buf0buf.c:
  Fixed compiler warning
storage/xtradb/buf/buf0lru.c:
  Initialize variable that could be used not initialized.
 2010-11-02 17:22:57 +02:00
unknown
fb8244a57c Merge latest MariaDB 5.1 into MWL#116. 2010-11-01 15:41:09 +01:00
Sergei Golubchik
8e7ebfbce8 5.2 merge 2010-10-28 19:04:23 +02:00
Sergei Golubchik
04a4b43346 merge with 5.1 2010-10-25 15:21:16 +02:00
Sergei Golubchik
60c15066db better fix for MySQL bugs 
BUG#26447 prefer a clustered key for an index scan, as secondary index is always slower
  ... which was fixed to cause
BUG#35850 queries take 50% longer
  ... and was reverted

and

BUG#39653 prefer a secondary index for an index scan, as clustered key is always slower
  ... which was fixed to cause
BUG#55656 mysqldump takes six days instead of half an hour
  ... and was amended with a special case workaround


sql/opt_range.cc:
  move get_index_only_read_time() into the handler class
sql/sql_select.cc:
  use cost not an index length when choosing a cheaper index
 2010-10-20 12:58:43 +02:00
Tor Didriksen
f0e2d8ecd8 Bug#52172 test binlog.binlog_index needs --skip-core-file to avoid leaving core files 
For crash testing: kill the server without generating core file.

include/my_dbug.h
  Use kill(getpid(), SIGKILL) which cannot be caught by signal handlers.
  All DBUG_XXX macros should be no-ops in optimized mode, do that for DBUG_ABORT as well.
sql/handler.cc
  Kill server without generating core.
sql/log.cc
  Kill server without generating core.
 2010-10-18 13:27:52 +02:00
Tor Didriksen
367549ab2b Bug#52172 test binlog.binlog_index needs --skip-core-file to avoid leaving core files 
For crash testing: kill the server without generating core file.

include/my_dbug.h
  Use kill(getpid(), SIGKILL) which cannot be caught by signal handlers.
  All DBUG_XXX macros should be no-ops in optimized mode, do that for DBUG_ABORT as well.
sql/handler.cc
  Kill server without generating core.
sql/log.cc
  Kill server without generating core.
 2010-10-18 13:27:52 +02:00
Tor Didriksen
9074307102 Bug#52172 test binlog.binlog_index needs --skip-core-file to avoid leaving core files 
For crash testing: kill the server without generating core file.

include/my_dbug.h
  Use kill(getpid(), SIGKILL) which cannot be caught by signal handlers.
  All DBUG_XXX macros should be no-ops in optimized mode, do that for DBUG_ABORT as well.
sql/handler.cc
  Kill server without generating core.
sql/log.cc
  Kill server without generating core.
 2010-10-18 13:24:34 +02:00
Tor Didriksen
0853153346 Bug#52172 test binlog.binlog_index needs --skip-core-file to avoid leaving core files 
For crash testing: kill the server without generating core file.

include/my_dbug.h
  Use kill(getpid(), SIGKILL) which cannot be caught by signal handlers.
  All DBUG_XXX macros should be no-ops in optimized mode, do that for DBUG_ABORT as well.
sql/handler.cc
  Kill server without generating core.
sql/log.cc
  Kill server without generating core.
 2010-10-18 13:24:34 +02:00
Sergey Petrunya
72dd7575cd Merge 5.2->5.3 
- Re-commit Monty's merge, partially fixed by Igor and SergeyP, 
  but still broken
 2010-10-10 17:18:11 +03:00
Davi Arnaut
a5efb91dea Bug#49938: Failing assertion: inode or deadlock in fsp/fsp0fsp.c 
Bug#54678: InnoDB, TRUNCATE, ALTER, I_S SELECT, crash or deadlock

- Incompatible change: truncate no longer resorts to a row by
row delete if the storage engine does not support the truncate
method. Consequently, the count of affected rows does not, in
any case, reflect the actual number of rows.

- Incompatible change: it is no longer possible to truncate a
table that participates as a parent in a foreign key constraint,
unless it is a self-referencing constraint (both parent and child
are in the same table). To work around this incompatible change
and still be able to truncate such tables, disable foreign checks
with SET foreign_key_checks=0 before truncate. Alternatively, if
foreign key checks are necessary, please use a DELETE statement
without a WHERE condition.

Problem description:

The problem was that for storage engines that do not support
truncate table via a external drop and recreate, such as InnoDB
which implements truncate via a internal drop and recreate, the
delete_all_rows method could be invoked with a shared metadata
lock, causing problems if the engine needed exclusive access
to some internal metadata. This problem originated with the
fact that there is no truncate specific handler method, which
ended up leading to a abuse of the delete_all_rows method that
is primarily used for delete operations without a condition.

Solution:

The solution is to introduce a truncate handler method that is
invoked when the engine does not support truncation via a table
drop and recreate. This method is invoked under a exclusive
metadata lock, so that there is only a single instance of the
table when the method is invoked.

Also, the method is not invoked and a error is thrown if
the table is a parent in a non-self-referencing foreign key
relationship. This was necessary to avoid inconsistency as
some integrity checks are bypassed. This is inline with the
fact that truncate is primarily a DDL operation that was
designed to quickly remove all data from a table.

mysql-test/suite/innodb/t/innodb-truncate.test:
  Add test cases for truncate and foreign key checks.
  Also test that InnoDB resets auto-increment on truncate.
mysql-test/suite/innodb/t/innodb.test:
  FK is not necessary, test is related to auto-increment.
  
  Update error number, truncate is no longer invoked if
  table is parent in a FK relationship.
mysql-test/suite/innodb/t/innodb_mysql.test:
  Update error number, truncate is no longer invoked if
  table is parent in a FK relationship.
  
  Use delete instead of truncate, test is used to check
  the interaction of FKs, triggers and delete.
mysql-test/suite/parts/inc/partition_check.inc:
  Fix typo.
mysql-test/suite/sys_vars/t/foreign_key_checks_func.test:
  Update error number, truncate is no longer invoked if
  table is parent in a FK relationship.
mysql-test/t/mdl_sync.test:
  Modify test case to reflect and ensure that truncate takes
  a exclusive metadata lock.
mysql-test/t/trigger-trans.test:
  Update error number, truncate is no longer invoked if
  table is parent in a FK relationship.
sql/ha_partition.cc:
  Reorganize the various truncate methods. delete_all_rows is now
  passed directly to the underlying engines, so as truncate. The
  code responsible for truncating individual partitions is moved
  to ha_partition::truncate_partition, which is invoked when a
  ALTER TABLE t1 TRUNCATE PARTITION p statement is executed.
  
  Since the partition truncate no longer can be invoked via
  delete, the bitmap operations are not necessary anymore. The
  explicit reset of the auto-increment value is also removed
  as the underlying engines are now responsible for reseting
  the value.
sql/handler.cc:
  Wire up the handler truncate method.
sql/handler.h:
  Introduce and document the truncate handler method. It assumes
  certain use cases of delete_all_rows.
  
  Add method to retrieve the list of foreign keys referencing a
  table. Method is used to avoid truncating tables that are
  parent in a foreign key relationship.
sql/share/errmsg-utf8.txt:
  Add error message for truncate and FK.
sql/sql_lex.h:
  Introduce a flag so that the partition engine can detect when
  a partition is being truncated. Used to give a special error.
sql/sql_parse.cc:
  Function mysql_truncate_table no longer exists.
sql/sql_partition_admin.cc:
  Implement the TRUNCATE PARTITION statement.
sql/sql_truncate.cc:
  Change the truncate table implementation to use the new truncate
  handler method and to not rely on row-by-row delete anymore.
  
  The truncate handler method is always invoked with a exclusive
  metadata lock. Also, it is no longer possible to truncate a
  table that is parent in some non-self-referencing foreign key.
storage/archive/ha_archive.cc:
  Rename method as the description indicates that in the future
  this could be a truncate operation.
storage/blackhole/ha_blackhole.cc:
  Implement truncate as no operation for the blackhole engine in
  order to remain compatible with older releases.
storage/federated/ha_federated.cc:
  Introduce truncate method that invokes delete_all_rows.
  This is required to support partition truncate as this
  form of truncate does not implement the drop and recreate
  protocol.
storage/heap/ha_heap.cc:
  Introduce truncate method that invokes delete_all_rows.
  This is required to support partition truncate as this
  form of truncate does not implement the drop and recreate
  protocol.
storage/ibmdb2i/ha_ibmdb2i.cc:
  Introduce truncate method that invokes delete_all_rows.
  This is required to support partition truncate as this
  form of truncate does not implement the drop and recreate
  protocol.
storage/innobase/handler/ha_innodb.cc:
  Rename delete_all_rows to truncate. InnoDB now does truncate
  under a exclusive metadata lock.
  
  Introduce and reorganize methods used to retrieve the list
  of foreign keys referenced by a or referencing a table.
storage/myisammrg/ha_myisammrg.cc:
  Introduce truncate method that invokes delete_all_rows.
  This is required in order to remain compatible with earlier
  releases where truncate would resort to a row-by-row delete.
 2010-10-06 11:34:28 -03:00
Davi Arnaut
5f911fa874 Bug#49938: Failing assertion: inode or deadlock in fsp/fsp0fsp.c 
Bug#54678: InnoDB, TRUNCATE, ALTER, I_S SELECT, crash or deadlock

- Incompatible change: truncate no longer resorts to a row by
row delete if the storage engine does not support the truncate
method. Consequently, the count of affected rows does not, in
any case, reflect the actual number of rows.

- Incompatible change: it is no longer possible to truncate a
table that participates as a parent in a foreign key constraint,
unless it is a self-referencing constraint (both parent and child
are in the same table). To work around this incompatible change
and still be able to truncate such tables, disable foreign checks
with SET foreign_key_checks=0 before truncate. Alternatively, if
foreign key checks are necessary, please use a DELETE statement
without a WHERE condition.

Problem description:

The problem was that for storage engines that do not support
truncate table via a external drop and recreate, such as InnoDB
which implements truncate via a internal drop and recreate, the
delete_all_rows method could be invoked with a shared metadata
lock, causing problems if the engine needed exclusive access
to some internal metadata. This problem originated with the
fact that there is no truncate specific handler method, which
ended up leading to a abuse of the delete_all_rows method that
is primarily used for delete operations without a condition.

Solution:

The solution is to introduce a truncate handler method that is
invoked when the engine does not support truncation via a table
drop and recreate. This method is invoked under a exclusive
metadata lock, so that there is only a single instance of the
table when the method is invoked.

Also, the method is not invoked and a error is thrown if
the table is a parent in a non-self-referencing foreign key
relationship. This was necessary to avoid inconsistency as
some integrity checks are bypassed. This is inline with the
fact that truncate is primarily a DDL operation that was
designed to quickly remove all data from a table.
 2010-10-06 11:34:28 -03:00
unknown
8bc445360e MWL#116: Efficient group commit 
Tweak the commit_ordered() semantics. Now it is only called for transactions
that go through 2-phase commit. This avoids forcing engines to make commits
visible before they are durable.

Also take LOCK_commit_ordered() around START TRANSACTION WITH CONSISTENT
SNAPSHOT, to get a truly consistent snapshot.
 2010-10-04 20:40:31 +02:00
unknown
498f10a2be Merge with latest MariaDB 5.1 2010-10-01 10:49:57 +02:00
unknown
0394cf2030 MWL#116: Efficient group commit for binary log 
Preliminary commit for testing
 2010-09-30 15:20:15 +02:00
Igor Babaev
b969df8bbd Merge of the mwl106 tree into the latest 5.3 tree. 
Resolved conflicts. Adjusted some test results
 2010-09-23 08:10:53 -07:00
Sergei Golubchik
e246077bcf rename maria to aria 2010-09-12 18:40:01 +02:00
Konstantin Osipov
523066987d A fix for Bug#41158 "DROP TABLE holds LOCK_open during unlink()". 
Remove acquisition of LOCK_open around file system operations,
since such operations are now protected by metadata locks.
Rework table discovery algorithm to not require LOCK_open.

No new tests added since all MDL locking operations are covered
in lock.test and mdl_sync.test, and as long as these tests
pass despite the increased concurrency, consistency must be
unaffected.

mysql-test/t/disabled.def:
  Disable NDB tests due to Bug#55799.
sql/datadict.cc:
  No longer necessary to protect ha_create_table() with
  LOCK_open. Serial execution is now ensured by metadata
  locks.
sql/ha_ndbcluster.cc:
  Do not manipulate with LOCK_open in cluster code.
sql/ha_ndbcluster_binlog.cc:
  Do not manipulate with LOCK_open in cluster code.
sql/ha_ndbcluster_binlog.h:
  Update function signature.
sql/handler.cc:
  Implement ha_check_if_table_exists().
  @todo: some engines provide ha_table_exists_in_engine()
  handlerton call, for those we perhaps shouldn't
  call ha_discover(), to be more efficient.
  Since currently it's only NDB, postpone till
  integration with NDB.
sql/handler.h:
  Declare ha_check_if_table_exists() function.
sql/mdl.cc:
  Remove an obsolete comment.
sql/sql_base.cc:
  Update to a new signature of close_cached_tables():
  from now on we always call it without LOCK_open.
  Update comments.
  Remove get_table_share_with_create(), we should
  not attempt to create a table under LOCK_open.
  Introduce get_table_share_with_discover() instead,
  which would request a back off action if the table
  exists in engine.
  Remove acquisition of LOCK_open for 
  data dictionary operations, such as check_if_table_exists().
  Do not use get_table_share_with_create/discover for views,
  where it's not needed.
  Make tdc_remove_table() optionally acquire LOCK_open
  to simplify usage of this function.
  Use the right mutex in the partitioning code when
  manipulating with thd->open_tables.
sql/sql_base.h:
  Update signatures of changes functions.
sql/sql_insert.cc:
  Do not wrap quick_rm_table() with LOCK_open acquisition, 
  this is unnecessary.
sql/sql_parse.cc:
  Update to the new calling convention of tdc_remove_table().
  Update to the new signature of close_cached_tables().
  Update comments.
sql/sql_rename.cc:
  Update to the new calling convention of tdc_remove_table().
  Remove acquisition of LOCK_open around filesystem
  operations.
sql/sql_show.cc:
  Remove get_trigger_table_impl().
  Do not acquire LOCK_open for a dirty read of the trigger
  file.
sql/sql_table.cc:
  Do not acquire LOCK_open for filesystem operations.
sql/sql_trigger.cc:
  Do not require LOCK_open for trigger file I/O.
sql/sql_truncate.cc:
  Update to the new signature of tdc_remove_table().
sql/sql_view.cc:
  Do not require LOCK_open for view I/O.
  Use tdc_remove_table() to expel view share.
  Update comments.
sql/sys_vars.cc:
  Update to the new signature of close_cached_tables().
 2010-08-09 22:33:47 +04:00
Konstantin Osipov
f8bfa3287d A fix for Bug#41158 "DROP TABLE holds LOCK_open during unlink()". 
Remove acquisition of LOCK_open around file system operations,
since such operations are now protected by metadata locks.
Rework table discovery algorithm to not require LOCK_open.

No new tests added since all MDL locking operations are covered
in lock.test and mdl_sync.test, and as long as these tests
pass despite the increased concurrency, consistency must be
unaffected.
 2010-08-09 22:33:47 +04:00
Michael Widenius
569c37163e Merge with MariaDB 5.1 2010-08-06 15:51:07 +03:00
Michael Widenius
50b43cf805 Fix for LP#614265 Crash in _ma_unpin_all_pages / _ma_search on DELETE with Aria search engine 
Fixed compiler warnings

client/mysqlslap.c:
  Fixed compiler warnings
mysql-test/suite/maria/r/maria.result:
  Test case for LP#614265
mysql-test/suite/maria/t/maria.test:
  Test case for LP#614265
mysql-test/suite/pbxt/t/skip_name_resolve-master.opt:
  Ensure that we get restart before test (as test uses show processlist)
sql/handler.cc:
  Added cloned marker if clone was called (for safety checks & debugging)
sql/handler.h:
  Added cloned marker if clone was called (for safety checks & debugging)
storage/maria/ha_maria.cc:
  In clone call, set file->trn if cloned file had this set. This is needed as maria_create_trn_for_mysql() and thus file->trn is never set for cloned table.
  Ensure that file->trn is properly reset after calls to repair/check/zerofill.
  Increment locked table count if file->trn is set (as we decrement this in the unlock call)
tests/mysql_client_test.c:
  Fixed compiler warnings
 2010-08-06 15:39:37 +03:00
Michael Widenius
d042146e5b Merge with MariaDB 5.1.49 
Removed references to HA_END_SPACE_KEY (which has been 0 for a long time)
 2010-08-05 22:56:11 +03:00
Michael Widenius
8cacc59e8f Disable some tests that is waiting for next merge with xtradb 
Added 'Aria' as an alias for the Maria storage engine. Real rename is happening in 5.2

sql/handler.cc:
  Added 'Aria' as an alias for the Maria storage engine.
 2010-08-02 12:22:36 +03:00
Konstantin Osipov
c4c678f653 Merge trunk-bugfixing -> trunk-runtime. 2010-07-27 18:32:42 +04:00
Konstantin Osipov
2abe7b9d4e Merge trunk-bugfixing -> trunk-runtime. 2010-07-27 18:32:42 +04:00
Konstantin Osipov
36290c0923 A pre-requisite patch for the fix for Bug#52044. 
This patch also fixes Bug#55452 "SET PASSWORD is
replicated twice in RBR mode".

The goal of this patch is to remove the release of 
metadata locks from close_thread_tables().
This is necessary to not mistakenly release
the locks in the course of a multi-step
operation that involves multiple close_thread_tables()
or close_tables_for_reopen().

On the same token, move statement commit outside 
close_thread_tables().

Other cleanups:
Cleanup COM_FIELD_LIST.
Don't call close_thread_tables() in COM_SHUTDOWN -- there
are no open tables there that can be closed (we leave
the locked tables mode in THD destructor, and this
close_thread_tables() won't leave it anyway).

Make open_and_lock_tables() and open_and_lock_tables_derived()
call close_thread_tables() upon failure.
Remove the calls to close_thread_tables() that are now
unnecessary.

Simplify the back off condition in Open_table_context.

Streamline metadata lock handling in LOCK TABLES 
implementation.

Add asserts to ensure correct life cycle of 
statement transaction in a session.

Remove a piece of dead code that has also become redundant
after the fix for Bug 37521.

mysql-test/r/variables.result:
  Update results: set @@autocommit and statement transaction/
  prelocked mode.
mysql-test/r/view.result:
  A harmless change in CHECK TABLE <view> status for a broken view.
  If previously a failure to prelock all functions used in a view 
  would leave the connection in LTM_PRELOCKED mode, now we call
  close_thread_tables() from open_and_lock_tables()
  and leave prelocked mode, thus some check in mysql_admin_table() that
  works only in prelocked/locked tables mode is no longer activated.
mysql-test/suite/rpl/r/rpl_row_implicit_commit_binlog.result:
  Fixed Bug#55452 "SET PASSWORD is replicated twice in
  RBR mode": extra binlog events are gone from the
  binary log.
mysql-test/t/variables.test:
  Add a test case: set autocommit and statement transaction/prelocked
  mode.
sql/event_data_objects.cc:
  Simplify code in Event_job_data::execute().
  Move sp_head memory management to lex_end().
sql/event_db_repository.cc:
  Move the release of metadata locks outside
  close_thread_tables().
  Make sure we call close_thread_tables() when
  open_and_lock_tables() fails and remove extra
  code from the events data dictionary.
  Use close_mysql_tables(), a new internal
  function to properly close mysql.* tables
  in the data dictionary.
  Contract Event_db_repository::drop_events_by_field,
  drop_schema_events into one function.
  When dropping all events in a schema,
  make sure we don't mistakenly release all
  locks acquired by DROP DATABASE. These
  include locks on the database name
  and the global intention exclusive
  metadata lock.
sql/event_db_repository.h:
  Function open_event_table() does not require an instance 
  of Event_db_repository.
sql/events.cc:
  Use close_mysql_tables() instead of close_thread_tables()
  to bootstrap events, since the latter no longer
  releases metadata locks.
sql/ha_ndbcluster.cc:
  - mysql_rm_table_part2 no longer releases
  acquired metadata locks. Do it in the caller.
sql/ha_ndbcluster_binlog.cc:
  Deploy the new protocol for closing thread
  tables in run_query() and ndb_binlog_index
  code.
sql/handler.cc:
  Assert that we never call ha_commit_trans/
  ha_rollback_trans in sub-statement, which
  is now the case.
sql/handler.h:
  Add an accessor to check whether THD_TRANS object
  is empty (has no transaction started).
sql/log.cc:
  Update a comment.
sql/log_event.cc:
  Since now we commit/rollback statement transaction in 
  mysql_execute_command(), we need a mechanism to communicate
  from Query_log_event::do_apply_event() to mysql_execute_command()
  that the statement transaction should be rolled back, not committed.
  Ideally it would be a virtual method of THD. I hesitate
  to make THD a virtual base class in this already large patch.
  Use a thd->variables.option_bits for now.
  
  Remove a call to close_thread_tables() from the slave IO
  thread. It doesn't open any tables, and the protocol
  for closing thread tables is more complicated now.
  
  Make sure we properly close thread tables, however, 
  in Load_data_log_event, which doesn't
  follow the standard server execution procedure
  with mysql_execute_command().
  @todo: this piece should use Server_runnable
  framework instead.
  Remove an unnecessary call to mysql_unlock_tables().
sql/rpl_rli.cc:
  Update Relay_log_info::slave_close_thread_tables()
  to follow the new close protocol.
sql/set_var.cc:
  Remove an unused header.
sql/slave.cc:
  Remove an unnecessary call to
  close_thread_tables().
sql/sp.cc:
  Remove unnecessary calls to close_thread_tables()
  from SP DDL implementation. The tables will
  be closed by the caller, in mysql_execute_command().
  When dropping all routines in a database, make sure
  to not mistakenly drop all metadata locks acquired
  so far, they include the scoped lock on the schema.
sql/sp_head.cc:
  Correct the protocol that closes thread tables
  in an SP instruction.
  Clear lex->sphead before cleaning up lex
  with lex_end to make sure that we don't
  delete the sphead twice. It's considered
  to be "cleaner" and more in line with
  future changes than calling delete lex->sphead
  in other places that cleanup the lex.
sql/sp_head.h:
  When destroying m_lex_keeper of an instruction,
  don't delete the sphead that all lex objects
  share. 
  @todo: don't store a reference to routine's sp_head
  instance in instruction's lex.
sql/sql_acl.cc:
  Don't call close_thread_tables() where the caller will
  do that for us.
  Fix Bug#55452 "SET PASSWORD is replicated twice in RBR 
  mode" by disabling RBR replication in change_password()
  function.
  Use close_mysql_tables() in bootstrap and ACL reload
  code to make sure we release all metadata locks.
sql/sql_base.cc:
  This is the main part of the patch:
  - remove manipulation with thd->transaction
  and thd->mdl_context from close_thread_tables().
  Now this function is only responsible for closing
  tables, nothing else.
  This is necessary to be able to easily use
  close_thread_tables() in procedures, that
  involve multiple open/close tables, which all
  need to be protected continuously by metadata
  locks.
  Add asserts ensuring that TABLE object
  is only used when is protected by a metadata lock.
  Simplify the back off condition of Open_table_context,
  we no longer need to look at the autocommit mode.
  Make open_and_lock_tables() and open_normal_and_derived_tables()
  close thread tables and release metadata locks acquired so-far 
  upon failure. This simplifies their usage.
  Implement close_mysql_tables().
sql/sql_base.h:
  Add declaration for close_mysql_tables().
sql/sql_class.cc:
  Remove a piece of dead code that has also become redundant
  after the fix for Bug 37521.
  The code became dead when my_eof() was made a non-protocol method,
  but a method that merely modifies the diagnostics area.
  The code became redundant with the fix for Bug#37521, when 
  we started to cal close_thread_tables() before
  Protocol::end_statement().
sql/sql_do.cc:
  Do nothing in DO if inside a substatement
  (the assert moved out of trans_rollback_stmt).
sql/sql_handler.cc:
  Add comments.
sql/sql_insert.cc:
  Remove dead code. 
  Release metadata locks explicitly at the
  end of the delayed insert thread.
sql/sql_lex.cc:
  Add destruction of lex->sphead to lex_end(),
  lex "reset" method called at the end of each statement.
sql/sql_parse.cc:
  Move close_thread_tables() and other related
  cleanups to mysql_execute_command()
  from dispatch_command(). This has become
  possible after the fix for Bug#37521.
  Mark federated SERVER statements as DDL.
  
  Next step: make sure that we don't store
  eof packet in the query cache, and move
  the query cache code outside mysql_parse.
  
  Brush up the code of COM_FIELD_LIST.
  Remove unnecessary calls to close_thread_tables().
  
  When killing a query, don't report "OK"
  if it was a suicide.
sql/sql_parse.h:
  Remove declaration of a function that is now static.
sql/sql_partition.cc:
  Remove an unnecessary call to close_thread_tables().
sql/sql_plugin.cc:
  open_and_lock_tables() will clean up
  after itself after a failure.
  Move close_thread_tables() above
  end: label, and replace with close_mysql_tables(),
  which will also release the metadata lock
  on mysql.plugin.
sql/sql_prepare.cc:
  Now that we no longer release locks in close_thread_tables()
  statement prepare code has become more straightforward.
  Remove the now redundant check for thd->killed() (used
  only by the backup project) from Execute_server_runnable.
  Reorder code to take into account that now mysql_execute_command()
  performs lex->unit.cleanup() and close_thread_tables().
sql/sql_priv.h:
  Add a new option to server options to interact
  between the slave SQL thread and execution
  framework (hack). @todo: use a virtual
  method of class THD instead.
sql/sql_servers.cc:
  Due to Bug 25705 replication of 
  DROP/CREATE/ALTER SERVER is broken.
  Make sure at least we do not attempt to 
  replicate these statements using RBR,
  as this violates the assert in close_mysql_tables().
sql/sql_table.cc:
  Do not release metadata locks in mysql_rm_table_part2,
  this is done by the caller.
  Do not call close_thread_tables() in mysql_create_table(),
  this is done by the caller. 
  Fix a bug in DROP TABLE under LOCK TABLES when,
  upon error in wait_while_table_is_used() we would mistakenly
  release the metadata lock on a non-dropped table.
  Explicitly release metadata locks when doing an implicit
  commit.
sql/sql_trigger.cc:
  Now that we delete lex->sphead in lex_end(),
  zero the trigger's sphead in lex after loading
  the trigger, to avoid double deletion.
sql/sql_udf.cc:
  Use close_mysql_tables() instead of close_thread_tables().
sql/sys_vars.cc:
  Remove code added in scope of WL#4284 which would
  break when we perform set @@session.autocommit along
  with setting other variables and using tables or functions.
  A test case added to variables.test.
sql/transaction.cc:
  Add asserts.
sql/tztime.cc:
  Use close_mysql_tables() rather than close_thread_tables().
 2010-07-27 14:25:53 +04:00
Konstantin Osipov
ec2c3bf2c1 A pre-requisite patch for the fix for Bug#52044. 
This patch also fixes Bug#55452 "SET PASSWORD is
replicated twice in RBR mode".

The goal of this patch is to remove the release of 
metadata locks from close_thread_tables().
This is necessary to not mistakenly release
the locks in the course of a multi-step
operation that involves multiple close_thread_tables()
or close_tables_for_reopen().

On the same token, move statement commit outside 
close_thread_tables().

Other cleanups:
Cleanup COM_FIELD_LIST.
Don't call close_thread_tables() in COM_SHUTDOWN -- there
are no open tables there that can be closed (we leave
the locked tables mode in THD destructor, and this
close_thread_tables() won't leave it anyway).

Make open_and_lock_tables() and open_and_lock_tables_derived()
call close_thread_tables() upon failure.
Remove the calls to close_thread_tables() that are now
unnecessary.

Simplify the back off condition in Open_table_context.

Streamline metadata lock handling in LOCK TABLES 
implementation.

Add asserts to ensure correct life cycle of 
statement transaction in a session.

Remove a piece of dead code that has also become redundant
after the fix for Bug 37521.
 2010-07-27 14:25:53 +04:00
Davi Arnaut
75e2212397 WL#5498: Remove dead and unused source code 
Remove unused macros or macro which are always defined.

include/my_global.h:
  Remove unused macros and move macros which aren't used globally.
 2010-07-23 17:16:29 -03:00
Davi Arnaut
60ab2b9283 WL#5498: Remove dead and unused source code 
Remove unused macros or macro which are always defined.
 2010-07-23 17:16:29 -03:00
Davi Arnaut
97c3182312 WL#5498: Remove dead and unused source code 
Remove code that has been disabled for a long time.
 2010-07-23 17:09:27 -03:00
Davi Arnaut
9fd9857e0b WL#5498: Remove dead and unused source code 
Remove code that has been disabled for a long time.
 2010-07-23 17:09:27 -03:00
Michael Widenius
e9166ca152 Fix for LP#588251: doStartTableScan() result not checked. 
The issue was that we didn't always check result of ha_rnd_init() which caused a problem for handlers that returned an error in this code.
- Changed prototype of ha_rnd_init() to ensure that we get a compile warning if result is not checked.
- Added ha_rnd_init_with_error() that prints error on failure.
- Checked all usage of ha_rnd_init() and ensure we generate an error message on failures.
- Changed init_read_record() to return 1 on failure.




sql/create_options.cc:
  Fixed wrong printf
sql/event_db_repository.cc:
  Check result from init_read_record()
sql/events.cc:
  Check result from init_read_record()
sql/filesort.cc:
  Check result from ha_rnd_init()
sql/ha_partition.cc:
  Check result from ha_rnd_init()
sql/ha_partition.h:
  Fixed compiler warning
sql/handler.cc:
  Added ha_rnd_init_with_error()
  Check result from ha_rnd_init()
sql/handler.h:
  Added ha_rnd_init_with_error()
  Changed prototype of ha_rnd_init() to ensure that we get a compile warning if result is not checked
sql/item_subselect.cc:
  Check result from ha_rnd_init()
sql/log.cc:
  Check result from ha_rnd_init()
sql/log_event.cc:
  Check result from ha_rnd_init()
sql/log_event_old.cc:
  Check result from ha_rnd_init()
sql/mysql_priv.h:
  init_read_record() now returns error code on failure
sql/opt_range.cc:
  Check result from ha_rnd_init()
sql/records.cc:
  init_read_record() now returns error code on failure
  Check result from ha_rnd_init()
sql/sql_acl.cc:
  Check result from init_read_record()
sql/sql_cursor.cc:
  Print error if ha_rnd_init() fails
sql/sql_delete.cc:
  Check result from init_read_record()
sql/sql_help.cc:
  Check result from init_read_record()
sql/sql_plugin.cc:
  Check result from init_read_record()
sql/sql_select.cc:
  Check result from ha_rnd_init()
  Print error if ha_rnd_init() fails.
sql/sql_servers.cc:
  Check result from init_read_record()
sql/sql_table.cc:
  Check result from init_read_record()
sql/sql_udf.cc:
  Check result from init_read_record()
sql/sql_update.cc:
  Check result from init_read_record()
storage/example/ha_example.cc:
  Don't return error on rnd_init()
storage/ibmdb2i/ha_ibmdb2i.cc:
  Removed not relevant comment
 2010-07-17 01:41:44 +03:00
unknown
2be1a25faa Automerge MariaDB 5.1->5.2. 2010-07-09 13:39:19 +02:00
Davi Arnaut
f56dd32bf7 Bug#34043: Server loops excessively in _checkchunk() when safemalloc is enabled 
Essentially, the problem is that safemalloc is excruciatingly
slow as it checks all allocated blocks for overrun at each
memory management primitive, yielding a almost exponential
slowdown for the memory management functions (malloc, realloc,
free). The overrun check basically consists of verifying some
bytes of a block for certain magic keys, which catches some
simple forms of overrun. Another minor problem is violation
of aliasing rules and that its own internal list of blocks
is prone to corruption.

Another issue with safemalloc is rather the maintenance cost
as the tool has a significant impact on the server code.
Given the magnitude of memory debuggers available nowadays,
especially those that are provided with the platform malloc
implementation, maintenance of a in-house and largely obsolete
memory debugger becomes a burden that is not worth the effort
due to its slowness and lack of support for detecting more
common forms of heap corruption.

Since there are third-party tools that can provide the same
functionality at a lower or comparable performance cost, the
solution is to simply remove safemalloc. Third-party tools
can provide the same functionality at a lower or comparable
performance cost. 

The removal of safemalloc also allows a simplification of the
malloc wrappers, removing quite a bit of kludge: redefinition
of my_malloc, my_free and the removal of the unused second
argument of my_free. Since free() always check whether the
supplied pointer is null, redudant checks are also removed.

Also, this patch adds unit testing for my_malloc and moves
my_realloc implementation into the same file as the other
memory allocation primitives.

client/mysqldump.c:
  Pass my_free directly as its signature is compatible with the
  callback type -- which wasn't the case for free_table_ent.
 2010-07-08 18:20:08 -03:00
Davi Arnaut
a10ae35328 Bug#34043: Server loops excessively in _checkchunk() when safemalloc is enabled 
Essentially, the problem is that safemalloc is excruciatingly
slow as it checks all allocated blocks for overrun at each
memory management primitive, yielding a almost exponential
slowdown for the memory management functions (malloc, realloc,
free). The overrun check basically consists of verifying some
bytes of a block for certain magic keys, which catches some
simple forms of overrun. Another minor problem is violation
of aliasing rules and that its own internal list of blocks
is prone to corruption.

Another issue with safemalloc is rather the maintenance cost
as the tool has a significant impact on the server code.
Given the magnitude of memory debuggers available nowadays,
especially those that are provided with the platform malloc
implementation, maintenance of a in-house and largely obsolete
memory debugger becomes a burden that is not worth the effort
due to its slowness and lack of support for detecting more
common forms of heap corruption.

Since there are third-party tools that can provide the same
functionality at a lower or comparable performance cost, the
solution is to simply remove safemalloc. Third-party tools
can provide the same functionality at a lower or comparable
performance cost. 

The removal of safemalloc also allows a simplification of the
malloc wrappers, removing quite a bit of kludge: redefinition
of my_malloc, my_free and the removal of the unused second
argument of my_free. Since free() always check whether the
supplied pointer is null, redudant checks are also removed.

Also, this patch adds unit testing for my_malloc and moves
my_realloc implementation into the same file as the other
memory allocation primitives.
 2010-07-08 18:20:08 -03:00
Sergey Petrunya
27f9fc063c MariaDB 5.2 -> MariaDB 5.3 merge 2010-06-26 14:05:41 +04:00
Michael Widenius
5a2f40d48a Fixes for Opensolaris (to get buildbot green) 
- Fixed memory leaks in mysqldump
- Fixed printf of NULL which caused crashes on OpenSolaris when using --debug
- Fixed realloc() problem that caused out of memory when running mysqldump.test on OpenSolaris


client/mysqldump.c:
  Fixed memory leaks
  Fixed printf of NULL which caused crashes on OpenSolaris when using --debug
client/mysqltest.cc:
  Fixed printf of NULL which caused crashes on OpenSolaris when using --debug
include/my_global.h:
  Added simple macro val_or_null() to simplify detecting of NULL strings for printf
sql/handler.cc:
  Fixed printf of NULL which caused crashes on OpenSolaris when using --debug
sql/sql_db.cc:
  Fixed printf of NULL which caused crashes on OpenSolaris when using --debug
  Removed testing of 'new_db_name' as this is guranteed never NULL
sql/sql_show.cc:
  Fixed printf of NULL which caused crashes on OpenSolaris when using --debug
storage/csv/ha_tina.cc:
  Fixed realloc() problem that caused out of memory when running mysqldump.test on OpenSolaris
  (OpenSolaris default malloc() can't handle a lot of reallocs() of strings that are growing one byte at a time)
  This did speed up logging to cvs with a magnitude for large strings.
 2010-06-23 03:48:11 +03:00
Magne Mahre
db716d11af Bug#20837 Apparent change of isolation level during transaction 
Bug#46527 COMMIT AND CHAIN RELEASE does not make sense
Bug#53343 completion_type=1, COMMIT/ROLLBACK AND CHAIN don't 
          preserve the isolation level
Bug#53346 completion_type has strange effect in a stored 
          procedure/prepared statement

Added test cases to verify the expected behaviour of :
 SET SESSION TRANSACTION ISOLATION LEVEL, 
 SET TRANSACTION ISOLATION LEVEL,
 @@completion_type,
 COMMIT AND CHAIN,
 ROLLBACK AND CHAIN
 ..and some combinations of the above
 2010-06-08 19:47:10 +02:00
Magne Mahre
0cb90edfe5 Bug#20837 Apparent change of isolation level during transaction 
Bug#46527 COMMIT AND CHAIN RELEASE does not make sense
Bug#53343 completion_type=1, COMMIT/ROLLBACK AND CHAIN don't 
          preserve the isolation level
Bug#53346 completion_type has strange effect in a stored 
          procedure/prepared statement

Added test cases to verify the expected behaviour of :
 SET SESSION TRANSACTION ISOLATION LEVEL, 
 SET TRANSACTION ISOLATION LEVEL,
 @@completion_type,
 COMMIT AND CHAIN,
 ROLLBACK AND CHAIN
 ..and some combinations of the above
 2010-06-08 19:47:10 +02:00