wsrep_cluster_address_update() causes LOCK_wsrep_slave_threads
to be locked under LOCK_wsrep_cluster_config, while normally
the order should be the opposite.
Fix: don't protect @@wsrep_cluster_address value with the
LOCK_wsrep_cluster_config, LOCK_global_system_variables is enough.
Only protect wsrep reinitialization with the LOCK_wsrep_cluster_config.
And make it use a local copy of the global @@wsrep_cluster_address.
Also, introduce a helper function that checks whether
wsrep_cluster_address is set and also asserts that it can be safely
read by the caller.
rarely (try --repeat 1000), the following happens:
* from wsrep_bf_abort (when a thread is being killed), wsrep-lib
starts streaming_rollback that wants to
convert_streaming_client_to_applier. wsrep_create_streaming_applier
creates a new THD(). All while the other THD is being killed,
so under LOCK_thd_kill and LOCK_thd_data. In particular, THD::init()
takes LOCK_global_system_variables under LOCK_thd_kill.
* updating @@wsrep_slave_threads takes LOCK_global_system_variables
and LOCK_wsrep_cluster_config (in that order) and invokes
wsrep_slave_threads_update() that takes LOCK_wsrep_slave_threads
* wsrep_replication_process() takes LOCK_wsrep_slave_threads and
invokes wsrep_close_applier(), that does thd->set_killed() which
takes LOCK_thd_kill.
et voilà.
As a fix I copied a workaround from wsrep_cluster_address_update()
to wsrep_slave_threads_update(). It seems to be safe: without mutexes
a race condition is possible and a concurrent SET might change
wsrep_slave_threads, but wsrep_slave_threads_update() always verifies
if there's a need to do something, so it will not run twice in this case,
it'll be a no-op.
* reuse the loop in THD::abort_current_cond_wait, don't duplicate it
* find_thread_by_id should return whatever it has found, it's the
caller's task not to kill COM_DAEMON (if the caller's a killer)
and other minor changes
A few of the failures was because of missing sync_slave_to_master in
the test suite.
However, the biggest reason for most faulures was that in case of
ALTER PARTITION the master writes the query to the binary log before
it has updated the .frm and .par files. This causes a problem for an
S3 slave as it will start execute the ALTER PARTITION but get old .frm and
.par files from S3 which causes "open table" to fail, either with an error
or in some case with a crash.
Fixed
One should not change the program arguments!
This change also reduces warnings from the icc compiler.
Almost all changes are just syntax changes (adding const to
'get_one_option function' declarations).
Other changes:
- Added a few cast of 'argument' from 'const char*' to 'char *'. This
was mainly in calls to 'external' functions we don't have control of.
- Ensure that all reset of 'password command line argument' are similar.
(In almost all cases it was just adding a comment and a cast)
- In mysqlbinlog.cc and mysqld.cc there was a few cases that changed
the command line argument. These places where changed to instead allocate
the option in a MEM_ROOT to avoid changing the argument. Some of this
code was changed to ensure that different programs did parsing the
same way. Added a test case for the changes in mysqlbinlog.cc
- Changed a few variables that took their value from command line options
from 'char *' to 'const char *'.
partially revert 76063c2a13. Item::clone() is not an all-purpose
Item copying machine, it was specifically created for pushdown
of predicates into derived tables and views and it does not
copy everything. In particular, it does not copy Item_func_regex.
Fix the bug differently by preserving the old constraint name.
But keep setting automatic_name=true to have it regenerated
for cases like ALTER TABLE ... ADD CONSTRAINT.
Since 2017 (c2118a08b1) THD::awake() no longer requires LOCK_thd_data.
It uses LOCK_thd_kill, and this latter mutex is used to prevent
a thread of dying, not LOCK_thd_data as before.
Also update the SEL_ARG graph weight in:
- sel_add()
- SEL_ARG::clone()
Make key_{and,or}_with_limit() to also verify weight for the arguments
(There is no single point to verify SEL_ARG graphs constructed from
conditions that are not AND-OR formulas, so we hope that those are
connected with AND/OR and do it here).
(Variant #5, full patch, for 10.5)
Do not produce SEL_ARG graphs that would yield huge numbers of ranges.
Introduce a concept of SEL_ARG graph's "weight". If we are about to
produce a graph whose "weight" exceeds the limit, remove the parts
of SEL_ARG graph that represent the biggest key parts. Do so until
the graph's is within the limit.
Includes
- debug code to verify SEL_ARG graph weight
- A user-visible @@optimizer_max_sel_arg_weight to control the optimization
- Logging the optimization into the optimizer trace.
The implementation for MDEV-17048 apperas to be direct copy from mysql version.
The group commit works differently in mariadb and the assert in wsrep_unregister_from_group_commit() is too strict.
The reason is that in: Wsrep_high_priority_service::log_dummy_write_set(), the transaction will undergo full rollback:
{
cs.before_rollback();
cs.after_rollback();
}
After that, the client's transaction state is set to be: wsrep::transaction::s_aborted.
The execution then continues execution by:
...
wsrep_register_for_group_commit(m_thd);
...
wsrep_unregister_from_group_commit(m_thd);
The bogus assert in wsrep_unregister_from_group_commit() allows only transactions states of :s_ordered_commit or s_aborting.
As the fix, I brought back the same assert as is present in MariaDB 10.4 version.
Apply the patch based on the patch by Varun Gupta:
PARAM::is_ror_scan might be used unitialized when check_quick_select()
is invoked for a "degenerate" SEL_ARG tree (e.g. one having type
SEL_ARG::IMPOSSIBLE).
Make check_quick_select() always initialize PARAM::is_ror_scan.
Ever since commit 007f68c37f,
ALTER TABLE no longer invokes handler::open() after
handler::commit_inplace_alter_table().
ha_innobase::reload_statistics(): Reload or recompute statistics
after ALTER TABLE.
innodb_notify_tabledef_changed(): A new function to invoke
ha_innobase::reload_statistics().
handlerton::notify_tabledef_changed(): Add the parameter handler*
so that ha_innobase::reload_statistics() can be invoked.
ha_partition::notify_tabledef_changed(),
partition_notify_tabledef_changed(): Pass through the call
to any partitions or subpartitions.
This is based on code that was supplied by Monty.
Problem is that not all plugins are loaded when wsrep_recover is executed.
Thus, we allow unknown system variables and extra system variables during
wsrep_recover. Any unknown system variables would still be caught when
the server starts up normally after the SST.
This patch actually fixes the bug MDEV-24675 and the bug MDEV-24618:
Assertion failure when TVC uses a row in the context expecting scalar value
The cause of these bugs is the same wrong call of the function that fixes
value expressions in the value list of a table value constructor.
The assertion failure happened when an expression in the value list is of
the row type. In this case an error message was expected, but it was not
issued because the function fix_fields_if_needed() was called for to
check fields of value expressions in a TVC instead of the function
fix_fields_if_needed_for_scalar() that would also check that the value
expressions are are of a scalar type.
The first bug happened when a table value expression used an expression
returned by single-row subselect. In this case the call of the
fix_fields_if_needed_for_scalar virtual function must be provided with
and address to which the single-row subselect has to be attached.
Test cases were added for each of the bugs.
Approved by Oleksandr Byelkin <sanja@mariadb.com>
The assertion failed in handler::ha_reset upon SELECT under
READ UNCOMMITTED from table with index on virtual column.
This was the debug-only failure, though the problem is mush wider:
* MY_BITMAP is a structure containing my_bitmap_map, the latter is a raw
bitmap.
* read_set, write_set and vcol_set of TABLE are the pointers to MY_BITMAP
* The rest of MY_BITMAPs are stored in TABLE and TABLE_SHARE
* The pointers to the stored MY_BITMAPs, like orig_read_set etc, and
sometimes all_set and tmp_set, are assigned to the pointers.
* Sometimes tmp_use_all_columns is used to substitute the raw bitmap
directly with all_set.bitmap
* Sometimes even bitmaps are directly modified, like in
TABLE::update_virtual_field(): bitmap_clear_all(&tmp_set) is called.
The last three bullets in the list, when used together (which is mostly
always) make the program flow cumbersome and impossible to follow,
notwithstanding the errors they cause, like this MDEV-17556, where tmp_set
pointer was assigned to read_set, write_set and vcol_set, then its bitmap
was substituted with all_set.bitmap by dbug_tmp_use_all_columns() call,
and then bitmap_clear_all(&tmp_set) was applied to all this.
To untangle this knot, the rule should be applied:
* Never substitute bitmaps! This patch is about this.
orig_*, all_set bitmaps are never substituted already.
This patch changes the following function prototypes:
* tmp_use_all_columns, dbug_tmp_use_all_columns
to accept MY_BITMAP** and to return MY_BITMAP * instead of my_bitmap_map*
* tmp_restore_column_map, dbug_tmp_restore_column_maps to accept
MY_BITMAP* instead of my_bitmap_map*
These functions now will substitute read_set/write_set/vcol_set directly,
and won't touch underlying bitmaps.
Cause: no table->update_handler cloned at the moment of
vers_insert_history_row(). update_handler is needed because there
can't be several inited indexes at once in the same handler. First
index is inited by QUICK_RANGE_SELECT::reset(). Then when history row
is inserted check_duplicate_long_entry_key() is done and it requires
another index.
mutex order violation here.
when wsrep bf thread kills a conflicting trx, the stack is
wsrep_thd_LOCK()
wsrep_kill_victim()
lock_rec_other_has_conflicting()
lock_clust_rec_read_check_and_lock()
row_search_mvcc()
ha_innobase::index_read()
ha_innobase::rnd_pos()
handler::ha_rnd_pos()
handler::rnd_pos_by_record()
handler::ha_rnd_pos_by_record()
Rows_log_event::find_row()
Update_rows_log_event::do_exec_row()
Rows_log_event::do_apply_event()
Log_event::apply_event()
wsrep_apply_events()
and mutexes are taken in the order
lock_sys->mutex -> victim_trx->mutex -> victim_thread->LOCK_thd_data
When a normal KILL statement is executed, the stack is
innobase_kill_query()
kill_handlerton()
plugin_foreach_with_mask()
ha_kill_query()
THD::awake()
kill_one_thread()
and mutexes are
victim_thread->LOCK_thd_data -> lock_sys->mutex -> victim_trx->mutex
To fix the mutex order violation we kill the victim thd asynchronously,
from the manager thread
* provide an argument to the callback
* don't ignore a callback request if it's already present in the queue
* initialize mutex/cond/in_use flag before starting the thread,
in case the first callback queueing request arrives before
handle_manager had time to initialize
* set/check abort_manager under a mutex, otherwise handle_manager
thread might destroy LOCK_manager before stop_handle_manager
released it
* signal COND on queueing a callback, stop cond_wait on callback request
* always start the thread, even if flush_time is 0
* but keep the old behavior in embedded (no replication, no galera)
* style cleanups (e.g. remove volatile for a variable protected by a mutex)
We need to complete SST if both new and old start positions are
not same as initial positions. If they are initial positions
just set local uuid and seqno.
Sample log error message generated:
2021-01-21 2:33:24 139912137520896 [Note] Slave SQL thread exiting, replication stopped in log 'master-bin.000001' at position 369
33:24 139912137520896 [Note] master was 127.0.0.1:16400
2021-01-21 2:33:24 139912137828096 [Note] Slave I/O thread exiting, read up to log 'master-bin.000001', position 369
2021-01-21 2:33:24 139912137828096 [Note] master was 127.0.0.1:16400
Based on work by Hartmut Holzgraefe.
Reviewer: knielsen@knielsen-hq.org, Andrei, Sachin
I_S tables were materialized too late, an attempt to use table
statistics before the table was created caused a crash.
Let's move table creation up. it only needs read_set to
be calculated properly, this happens in JOIN::optimize_inner(),
after semijoin transformation.
Note that tables are not populated at that point, so most of the
statistics would make no sense anyway. But at least field sizes
will be correct. And it won't crash.
There were multiple problems here
* wsrep_trx_fragment_size should not be set when wsrep is disabled or provider is not loaded
* wsrep_trx_fragment_unit should not be set when wsrep is disabled or provider is not loaded
* wsrep_debug has no effect if wsrep is disabled or provider is not loaded
* wsrep_start_position should not be set when wsrep is disabled or provider is not loaded any other value than default
* wsrep_start_position should be changed only when we are joiner or initialized
* wsrep_start_position should be allowed to set only a value that exits, thus
we need to add error handling to wsrep_sst_complete
Problem:
========
Auto purge of relaylogs stops when relay-log-file is
'slave-relay-log.999999' and slave_parallel_threads is enabled.
Analysis:
=========
The problem is that in Relay_log_info::inc_group_relay_log_pos() function,
when two log names are compared via strcmp() function, it gives correct
result, when log name sequence numbers are of same digits(6 digits), But
when the number goes to 7 digits, a 999999 compares greater than
1000000, which is wrong, hence the bug.
Fix:
====
Extract the numeric extension part of the file name, convert it into
unsigned long and compare.
Thanks to David Zhao for the contribution.
Fix for MDEV-23033 fixes a problem in replication applying of transactions, which contain cascading foreign key delete for a table, which has indexed virtual column.
This fix adds slave_fk_event_map flag for table, to mark when the prelocking is needed for applying of a transaction.
See commit 608b0ee52e for more details.
However, this fix is targeted for async replication only, Rows_log_event::do_apply_event() has condition to rule out galera replication from the fix domain, and use cases suffering from MDEV-23033 and related MDEV-21153 will fail in galera cluster.
The fix in this commit removes the condition to rule out the setting of slave_fk_event_map flag from galera replication, and makes the fix in MDEV-23033 effective for galera replication as well.
However, the above fix has caused regressions for some galera_sr suite tests, which run tests for streaming replication.
This regression can be observed e.g. by: /mtr galera_sr.galera_sr_multirow_rollback --mysqld=--slave_run_triggers_for_rbr=yes
These galera_sr suite tests were failing in last phase of replication applying, where actual transaction is already applied, and streaming replication related meta data needs to be updated in wsrep system tables.
Opening the wsrep system tables failed for corrupt data in THD::lex:query_tables_list. The fix in this commit uses back query table list for the duration of fragment update operation.
Finally, a mtr test for virtual column support has been added. galera.galera_virtual_column.test has as first test a scenario from MDEV-21153
new fix
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
through 2nd execution of SP
This bug caused a server crash on the second call of any stored procedure
that contained an UPDATE statement over a multi-table view reporting an
error message at the prepare stage.
On the first call of the stored procedure after reporting an error at
the preparation stage of the UPDATE statement finished without calling
the function SELECT_LEX::save_prep_leaf_tables() for the SELECT used as
the definition of the view. This left the SELECT_LEX structure used by
the UPDATE statement in an inconsistent state for second call of the stored
procedure.
Approved by Oleksandr Byelkin <sanja@mariadb.com>
m_status == DA_OK_BULK' failed in Diagnostics_area::message()
Analysis: Assertion failure happens because we reach the maximum limit to
examine rows.
Fix: Return the error state.
Fix for MDEV-23033 fixes a problem in replication applying of transactions, which contain cascading foreign key delete for a table, which has indexed virtual column.
This fix adds slave_fk_event_map flag for table, to mark when the prelocking is needed for applying of a transaction.
See commit 608b0ee52e for more details.
However, this fix is targeted for async replication only, Rows_log_event::do_apply_event() has condition to rule out galera replication from the fix domain, and use cases suffering from MDEV-23033 and related MDEV-21153 will fail in galera cluster.
The fix in this commit removes the condition to rule out the setting of slave_fk_event_map flag from galera replication, and makes the fix in MDEV-23033 effective for galera replication as well.
Finally, a mtr test for virtual column support has been added. galera.galera_virtual_column.test has as first test a scenario from MDEV-21153
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
Some DML operations on tables having unique secondary keys cause scanning
in the secondary index, for instance to find potential unique key violations
in the seconday index. This scanning may involve GAP locking in the index.
As this locking happens also when applying replication events in high priority
applier threads, there is a probabality for lock conflicts between two wsrep
high priority threads.
This PR avoids lock conflicts of high priority wsrep threads, which do
secondary index scanning e.g. for duplicate key detection.
The actual fix is the patch in sql_class.cc:thd_need_ordering_with(), where
we allow relaxed GAP locking protocol between wsrep high priority threads.
wsrep high priority threads (replication appliers, replayers and TOI processors)
are ordered by the replication provider, and they will not need serializability
support gained by secondary index GAP locks.
PR contains also a mtr test, which exercises a scenario where two replication
applier threads have a false positive conflict in GAP of unique secondary index.
The conflicting local committing transaction has to replay, and the test verifies
also that the replaying phase will not conflict with the latter repllication applier.
Commit also contains new test scenario for galera.galera_UK_conflict.test,
where replayer starts applying after a slave applier thread, with later seqno,
has advanced to commit phase. The applier and replayer have false positive GAP
lock conflict on secondary unique index, and replayer should ignore this.
This test scenario caused crash with earlier version in this PR, and to fix this,
the secondary index uniquenes checking has been relaxed even further.
Now innodb trx_t structure has new member: bool wsrep_UK_scan, which is set to
true, when high priority thread is performing unique secondary index scanning.
The member trx_t::wsrep_UK_scan is defined inside WITH_WSREP directive, to make
it possible to prepare a MariaDB build where this additional trx_t member is
not present and is not used in the code base. trx->wsrep_UK_scan is set to true
only for the duration of function call for: lock_rec_lock() trx->wsrep_UK_scan
is used only in lock_rec_has_to_wait() function to relax the need to wait if
wsrep_UK_scan is set and conflicting transaction is also high priority.
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>