Do not SET DEBUG_DBUG=-d,... in tests. To disable debug instrumentation,
save and restore the original value of the variable DEBUG_DBUG.
Assigning -d,... will enable the output of a lot of unrelated DBUG
messages to the server error log.
Tests started to fail after a merge of MDEV-15107 (from bb-10.2-ext to 10.3),
because MDEV-15107 additionally fixed this problem:
MDEV-15112 Inconsistent evaluation of spvariable=0 in strict mode
Modifying tests not to reply on the pre-MDEV-15112 behavior.
Remove unnecessary repeated lookups for undo pages.
trx_undo_assign(), trx_undo_assign_low(), trx_undo_seg_create(),
trx_undo_create(): Return the undo log block to the caller.
Inside InnoDB, each mini-transaction that generates any redo log records
will acquire log_sys->mutex during mtr_t::commit() in order to copy the
records into the global log_sys->buf for writing into the redo log file.
For single-row transactions, this incurs quite a bit of overhead.
We would use two mini-transactions for writing a record into a
freshly updated undo log page. (Only if the undo record will
not fit in that page, then we will have to commit and restart
the mini-transaction.)
trx_undo_assign(): Assign undo log for a persistent transaction,
or return the already assigned one.
trx_undo_assign_low(): Assign undo log for an operation on a
persistent or temporary table.
trx_undo_create(), trx_undo_reuse_cached(): Remove redundant parameters.
Merge the logic from trx_undo_mark_as_dict_operation().
After MDEV-14212, the Virtual_tmp_table instance that stores a ROW
variable elements is accessible from the underlying Field_row
(rather than Item_field_row).
This patch makes some further changes by moving the code from
sp_instr_xxx, sp_rcontext, Item_xxx to Virtual_tmp_table and Field_xxx.
The data type specific code (scalar vs ROW) now resides in
a new virtual method Field_xxx::sp_prepare_and_store_item().
The the code in sp_rcontext::set_variable() and sp_eval_expr()
is now symmetric for scalar and ROW values.
The code in sp_rcontext::set_variable_row_field(), sp_rcontext::set_variable_row_field(), sp_rcontext::set_variable_row()
is now symmetric for ROW elements (i.e. scalar and ROW elements inside a ROW).
Rationale:
Prepare the code to implement these tasks soon easier:
- MDEV-12252 ROW data type for stored function return values
- MDEV-12307 ROW data type for built-in function return values
- MDEV-6121 Data type: Array
- MDEV-10593 sql_mode=ORACLE: TYPE .. AS OBJECT: basic functionality
- ROW with ROW fields (no MDEV yet)
Details:
1. Moving the code in sp_eval_expr() responsible to backup/restore
thd->count_cuted_fields, thd->abort_on_warning,
thd->transaction.stmt.modified_non_trans_table
into a new helper class Sp_eval_expr_state, to reuse it easier.
Fixing sp_eval_expr() to use this new class.
2. Moving sp_eval_expr() and sp_prepare_func_item() from public functions
to methods in THD, so they can be reused in *.cc files easier without
a need to include "sp_head.h".
Splitting sp_prepare_func_item() into two parts.
Adding a new function sp_fix_func_item(), which fixes
the underlying items, but does not do check_cols() for them.
Reusing sp_fix_func_item() in Field_row::sp_prepare_and_store_item().
3. Moving the code to find ROW fields by name from Item to Virtual_tmp_table
Moving the code searching for ROW fields by their names
from Item_field_row::element_index_by_name() to a new method
Item_field_row to Virtual_tmp_table::sp_find_field_by_name().
Adding wrapper methods sp_rcontext::find_row_field_by_name() and
find_row_field_by_name_or_error(), to search for a ROW variable
fields by the variable offset and its field name.
Changing Item_splocal_row_field_by_name::fix_fields() to do
use sp_rcontext::find_row_field_by_name_or_error().
Removing virtual Item::element_index_by_name().
4. Splitting sp_rcontext::set_variable()
Adding a new virtual method Field::sp_prepare_and_store_item().
Spliting the two branches of the code in sp_rcontext::set_variable()
into two virtual implementations of Field::sp_prepare_and_store_item(),
(for Field and for Field_row).
Moving the former part of sp_rcontext::set_variable() with the loop
doing set_null() for all ROW fields into a new method
Virtual_tmp_table::set_all_fields_to_null() and using it in
Field_row::sp_prepare_and_store_item().
Moving the former part of sp_rcontext::set_variable() with the loop
doing set_variable_row_field() into a new method
Virtual_tmp_table::set_all_fields_from_item() and using it in
Field_row::sp_prepare_and_store_item().
The loop in the new method now uses sp_prepare_and_store_item()
instead of set_variable_row_field(), because saving/restoring
THD flags is now done on the upper level. No needs to save/restore
on every iteration.
5. Fixing sp_eval_expr() to simply do two things:
- backup/restore THD flags
- call result_field->sp_prepare_and_store_item()
So now sp_eval_expr() can be used for both scalar and ROW variables.
Reusing it in sp_rcontext::set_variable*().
6. Moving the loop in sp_rcontext::set_variable_row() into a
new method Virtual_tmp_table::sp_set_all_fields_from_item_list().
Changing the loop body to call field->sp_prepare_and_store_item()
instead of doing set_variable_row_field(). This removes
saving/restoring of the THD flags from every interation.
Instead, adding the code to save/restore the flags around
the entire loop in set_variable_row(), using Sp_eval_expr_state.
So now saving/restoring is done only once for the entire ROW
(a slight performance improvement).
7. Removing the code in sp_instr_set::exec_core() that sets
a variable to NULL if the value evaluation failed.
sp_rcontext::set_variable() now makes sure to reset
the variable properly by effectively calling sp_eval_expr(),
which calls virtual Field::sp_prepare_and_store_item().
Removing the similar code from sp_instr_set_row_field::exec_core()
and sp_instr_set_row_field_by_name::exec_core().
Removing the method sp_rcontext::set_variable_row_field_to_null(),
as it's not used any more.
8. Removing the call for sp_prepare_func_item() from
sp_rcontext::set_variable_row_field(), as it was duplicate:
it was done inside sp_eval_expr(). Now it's done inside
virtual Field::sp_prepare_and_store_item().
9. Moving the code from sp_instr_set_row_field_by_name::exec_core()
into sp_rcontext::set_variable_row_field_by_name(), for symmetry
with other sp_instr_set*::exec_core()/sp_rcontext::set_variable*() pairs.
Now sp_instr_set_row_field_by_name::exec_core() calls
sp_rcontext::set_variable_row_field_by_name().
10. Misc:
- Adding a helper private method sp_rcontext::virtual_tmp_table_for_row(),
reusing it in a new sp_rcontext methods.
- Removing Item_field_row::get_row_field(), as it's not used any more.
- Removing the "Item *result_item" from sp_eval_expr(),
as it's not needed any more.
Solve 3 way deadlock between plugin_initialiaze(), THD::init() and
mysql_sys_var_char().
The deadlock exists because of the lock order inversion between
LOCK_global_system_variables mutex and LOCK_system_variables_hash
read-write lock-
In this case, it is enough to change LOCK_system_variables_hash to prefer
reads to fix the deadlock, i.e change it to mysql_prlock_t
Now we don't open partitions if it was explicitly cpecified.
ha_partition::m_opened_partition bitmap added to track
partitions that were actually opened.
Only invoke set_versioned() on trx_id versioned tables.
dict_table_t::versioned_by_id(): New accessor, to determine if
a table is system versioned by transaction ID.
One can use -DTRASH_FREED_MEMORY to enable TRASH
macros. Useful to do when one suspects that there
is accesses to freed memory.
Extended my_free() to TRASH freed memory
replicate_events_marked_for_skip=FILTER_ON_MASTER
When events of a big transaction are binlogged offsetting over 2GB from
the beginning of the log the semisync master's dump thread
lost such events.
The events were skipped by the Dump thread that found their skipping
status erroneously.
The current fixes make sure the skipping status is computed correctly.
The test verifies them simulating the 2GB offset.
When cloning oldest view, don't copy ReadView::m_creator_trx_id.
It means that the owner thread is now allowed to access this member
without trx_sys.mutex protection.
To achieve this we have to keep ReadView::m_creator_trx_id in
ReadView::m_ids. This is required to not let purge thread process
records owned by transaction associated with oldest view.
It is only required if trsanction entered read-write mode before it's
view was created.
If transaction entered read-write mode after it's view was created
(trx_set_rw_mode()), purge thread won't be allowed to touch it because
m_low_limit_id >= m_creator_trx_id holds. Thus we don't have to add
this transaction id to ReadView::m_ids.
Cleanups:
ReadView::ids_t: don't seem to make any sense, just complicate matters.
ReadView::copy_trx_ids(): doesn't make sense anymore, integrated into
caller.
ReadView::copy_complete(): not needed anymore.
ReadView copy constructores: don't seem to make any sense.
trx_purge_truncate_history(): removed view argument, access
purge_sys->view directly instead.
Moved mutex locking inside lock_rec_lock().
Moved monitor increment out of mutex.
Moved assertions that don't require protection out of mutex.
Removed duplicate assertions.
Moved duplicate debug injections into lock_rec_lock().
Let monitor updates use relaxed memory order.
Return directly without maintaining variables in lock_rec_lock_slow().
Moved lock_rec_lock_fast() body into lock_rec_lock(): saves at least one
trx_mutex_enter(), one switch() plus some code was moved out of mutex.
InnoDB RNG maintains global state, causing otherwise unnecessary bus
traffic. Even worse this is cross-mutex traffic. That is different
mutexes suffer from contention.
Fixed delay of 4 was verified to give best throughput by OLTP update
index and read-write benchmarks on Intel Broadwell (2/20/40) and
ARM (1/46/46).
Traditionally, DROP TABLE and TRUNCATE TABLE discarded any locks that
may have been held on the table. This feels like an ACID violation.
Probably most occurrences of it were prevented by meta-data locks (MDL)
which were introduced in MySQL 5.5.
dict_table_t::n_foreign_key_checks_running: Reduce the number of
non-debug checks.
lock_remove_all_on_table(), lock_remove_all_on_table_for_trx(): Remove.
ha_innobase::truncate(): Acquire an exclusive InnoDB table lock
before proceeding. DROP TABLE and DISCARD/IMPORT were already doing
this.
row_truncate_table_for_mysql(): Convert the already started transaction
into a dictionary operation, and do not invoke lock_remove_all_on_table().
row_mysql_table_id_reassign(): Do not call lock_remove_all_on_table().
This function is only used in ALTER TABLE...DISCARD/IMPORT TABLESPACE,
which is already holding an exclusive InnoDB table lock.
TODO: Make n_foreign_key_checks running a debug-only variable.
This would require two fixes:
(1) DROP TABLE: Exclusively lock the table beforehand, to prevent
the possibility of concurrently running foreign key checks (which
would acquire a table IS lock and then record S locks).
(2) RENAME TABLE: Find out if n_foreign_key_checks_running>0 actually
constitutes a potential problem.
Assertion `count > 0' failed in rpl_parallel_thread_pool::
get_thread, rpl.rpl_parallel failed in buildbot
The reason for this is that one thread can call
rpl_parallel_resize_pool_if_no_slaves() while
another thread calls at the same time
rpl_parallel_activate_pool(). If rpl_parallel_active_pool() is
called before rpl_parallel_resize_pool_if_no_slaves() has
finished, pool->count will be set to 0 even if there exists
active slave threads.
Added a mutex lock in rpl_parallel_activate_pool() to protect against this scenario, which seams to fix this issue.
