Merged from mysql-wsrep-bugs following:
GCF-1058 MTR test galera.MW-86 fails on repeated runs
Wait for the sync point sync.wsrep_apply_cb to be reached before
executing the test and clearing the debug flag sync.wsrep_apply_cb.
The race scenario:
Intended behavior:
node2: set sync.wsrep_apply_cb in order to start waiting in the background INSERT
node1: INSERT start
node2 (background): INSERT start
node1: INSERT end
node2: send signal to background INSERT: "stop waiting and continue executing"
node2: clear sync.wsrep_apply_cb as no longer needed
node2 (background): consume the signal
node2 (background): INSERT end
node2: DROP TABLE
node2: check no pending signals are left - ok
What happens occasionally (unexpected):
node2: set sync.wsrep_apply_cb in order to start waiting in the background INSERT
node1: INSERT start
node2 (background): INSERT start
node1: INSERT end
// The background INSERT still has _not_ reached the place where it starts
// waiting for the signal:
// DBUG_EXECUTE_IF("sync.wsrep_apply_cb", "now wait_for...");
node2: send signal to background INSERT: "stop waiting and continue executing"
node2: clear sync.wsrep_apply_cb as no longer needed
// The background INSERT reaches DBUG_EXECUTE_IF("sync.wsrep_apply_cb", ...)
// but sync.wsrep_apply_cb has already been cleared and the "wait" code is not
// executed. The signal remains unconsumed.
node2 (background): INSERT end
node2: DROP TABLE
node2: check no pending signals are left - failure, signal.wsrep_apply_cb is
pending (not consumed)
Remove MW-360 test case as it is not intended for MariaDB (uses
MySQL GTID).
Sync waiting before processing SQLCOM_REPLACE was not necessary given that
this case falls through to processing of SQLCOM_INSERT. In case of
SQLCOM_REPLACE, wsrep_sync_wait would be called twice.
Previously, setting `wsrep_sync_wait = 1` would have an effect on
both SELECT and SHOW statements.
This patch changes wsrep_sync_wait so that bitmask value 1 is used
for SELECT statements, while bitmask value 8 is reserved for SHOW
statements.
It is still possible to achieve sync wait on both SELECT and SHOW
statements by setting `wsrep_sync_wait = 9`.
The problem was that the introduction of max-thread-mem-used can cause
an allocation error very early, even before mysql_parse() is called.
As mysql_parse() calls thd->reset_for_next_command(), which called
clear_error(), the error number was lost.
Fixed by adding an option to have unique messages for each KILL
signal and change max-thread-mem-used to use this new feature.
This removes a lot of problems with the original approach, where
one could get errors signaled silenty almost any time.
ixed by moving clear_error() from reset_for_next_command() to
do_command(), before any memory allocation for the thread.
Related changes:
- reset_for_next_command() now have an optional parameter if we should
call clear_error() or not. By default it's called, but not anymore from
dispatch_command() which was the original problem.
- Added optional paramater to clear_error() to force calling of
reset_diagnostics_area(). Before clear_error() only called
reset_diagnostics_area() if there was no error, so we normally
called reset_diagnostics_area() twice.
- This change removed several duplicated calls to clear_error()
when starting a query.
- Reset max_mem_used on COM_QUIT, to protect against kill during
quit.
- Use fatal_error() instead of setting is_fatal_error (cleanup)
- Set fatal_error if max_thead_mem_used is signaled.
(Same logic we use for other places where we are out of resources)
CREATE/DROP TEMPORARY TABLE are not safe to optimistically replicate in
parallel with other transactions, so they need to be marked as "ddl" in the
binlog.
This was already done for stand-alone CREATE/DROP TEMPORARY. But temporary
tables can also be created and dropped inside a BEGIN...END transaction, and
such transactions were not marked as ddl. Nor was the DROP TEMPORARY TABLE
statement emitted implicitly when a client connection is closed.
So this patch adds such ddl mark for the missing cases.
The difference to Kristian's original patch is mainly a fix in
mysql_trans_commit_alter_copy_data() to remember the unsafe_rollback_flags
over the temporary commit.
Do not silence uncertain cases, or fix any bugs.
The only functional change should be that ha_federated::extra()
is not calling DBUG_PRINT to report an unhandled case for
HA_EXTRA_PREPARE_FOR_DROP.
Do not silence uncertain cases, or fix any bugs.
The only functional change should be that ha_federated::extra()
is not calling DBUG_PRINT to report an unhandled case for
HA_EXTRA_PREPARE_FOR_DROP.
PRIVILEGE.
Backport from mysql-5.7 to mysql-5.5 and mysql-5.6.
BUG#13969578: TEMPORARY TABLE IN A DATABASE ON A READ-ONLY
INSTANCE CAN BE OVERWRITTEN
Analysis:
========
Creation or modification of a persistent table by a non-super user
is NOT ALLOWED in read_only mode. Only TEMPORARY tables are allowed
to be created or modified in read_only mode. But the creation of
a persistent table was being allowed when a temporary table of
the same name existed.
The routine which denies updating a non-temporary table in a
read_only mode does not handle the case of creation of a regular
table when a temporary table of the same exists.
Fix:
===
Handled the condition where an attempt is made to create a persistent
table having the same name as that of the temporary table. Hence
the creation of a persistent table by a non-super user when a
temporary table of the same exists is denied under read_only mode.
Also, implement MDEV-11027 a little differently from 5.5 and 10.0:
recv_apply_hashed_log_recs(): Change the return type back to void
(DB_SUCCESS was always returned).
Report progress also via systemd using sd_notifyf().
The reason for this is that stop slave takes LOCK_active_mi over the
whole operation while some slave operations will also need LOCK_active_mi
which causes deadlocks.
Fixed by introducing object counting for Master_info and not taking
LOCK_active_mi over stop slave or even stop_all_slaves()
Another benefit of this approach is that it allows:
- Multiple threads can run SHOW SLAVE STATUS at the same time
- START/STOP/RESET/SLAVE STATUS on a slave will not block other slaves
- Simpler interface for handling get_master_info()
- Added some missing unlock of 'log_lock' in error condtions
- Moved rpl_parallel_inactivate_pool(&global_rpl_thread_pool) to end
of stop_slave() to not have to use LOCK_active_mi inside
terminate_slave_threads()
- Changed argument for remove_master_info() to Master_info, as we always
have this available
- Fixed core dump when doing FLUSH TABLES WITH READ LOCK and parallel
replication. Problem was that waiting for pause_for_ftwrl was not done
when deleting rpt->current_owner after a force_abort.
Problem: CREATE TABLE using a fully qualified name with INDEX DIR/DATA DIR
option reports an error when the current database is not SET.
check_access() was incorrectly called with NULL as the database
argument in a situation where the database name was not needed for
the particular privilege being checked. This will cause the current
database to be used, or an error to be reported if there is no current
database.
Fix: Call check_access() with any_db as the database argument in this situation.
that must not send a response
Problem:- When using wsrep (w/ galera) and issuing commands that can
cause deadlocks, deadlock exception errors are sent in responses to
commands such as close prepared statement and close connection which,
by spec, must not send a response.
Solution:- In dispatch_command, we will handle COM_QUIT and COM_STMT_CLOSE
commands even in case of error.
Patch Credit:- Jaka Močnik
This commit is for optimizing WSREP(thd) macro.
#define WSREP(thd) \
(WSREP_ON && wsrep && (thd && thd->variables.wsrep_on))
In this we can safely remove wsrep and thd. We are not removing WSREP_ON
because this will change WSREP(thd) behaviour.
Patch Credit:- Nirbhay Choubay, Sergey Vojtovich
Problem:-
The condition that checks for node readiness is too strict as it does
not allow SELECTs even if these selects do not access any tables.
For example,if we run
SELECT 1;
OR
SELECT @@max_allowed_packet;
Solution:-
We need not to report this error when all_tables(lex->query_tables)
is NULL:
Tasks:-
Changes in wsrep_dirty_reads variable
1.) Global + Session scope (Current: session-only)
2.) Can be set using command line.
3.) Allow all commands that do not change data (besides SELECT)
4.) Allow prepared Statements that do not change data
5.) Works with wsrep_sync_wait enabled
Tasks:-
Changes in wsrep_dirty_reads variable
1.) Global + Session scope (Current: session-only)
2.) Can be set using command line.
3.) Allow all commands that do not change data (besides SELECT)
4.) Allow prepared Statements that do not change data
5.) Works with wsrep_sync_wait enabled
