When an rpl_group_info object was returned from the free list, the
rgi->deferred_events_collecting and rgi->deferred_events was not correctly
re-inited. Additionally, the rgi->deferred_events was incorrectly freed in
free_rgi(), which causes unnecessary malloc/free (or crash when re-init is not
done).
Thanks to user nanyi607rao, who reported this bug on maria-developers@.
The problem was when a GTID event was part of a group commit, and so contained
a commit id. The code that replaces GTID with a BEGIN event for old slaves did
not correctly handle this case.
Fix the code so that the GTID with commit id can also be properly replaced
with a BEGIN query event. The extra two bytes are in the BEGIN event replaced
with a dummy, empty time zone string.
Older master has no GTID events, so such events are not available for
deciding on scheduling of event groups and so on.
With this patch, we run such events from old masters single-threaded, in the
sql driver thread.
This seems better than trying to make the parallel code handle the data from
older masters; while possible, this would require a lot of testing (as well as
possibly some extra overhead in the scheduling of events), which hardly seems
worthwhile.
Fix ha_table_exists() to take discovery into account correctly.
It must be able to discover both table existence (when no frm is
found) and table non-existance (when frm was found).
Clean up and improve the parallel implementation code, mainly related to
scheduling of work to threads and handling of stop and errors.
Fix a lot of bugs in various corner cases that could lead to crashes or
corruption.
Fix that a single replication domain could easily grab all worker threads and
stall all other domains; now a configuration variable
--slave-domain-parallel-threads allows to limit the number of
workers.
Allow next event group to start as soon as previous group begins the commit
phase (as opposed to when it ends it); this allows multiple event groups on
the slave to participate in group commit, even when no other opportunities for
parallelism are available.
Various fixes:
- Fix some races in the rpl.rpl_parallel test case.
- Fix an old incorrect assertion in Log_event iocache read.
- Fix repeated malloc/free of wait_for_commit and rpl_group_info objects.
- Simplify wait_for_commit wakeup logic.
- Fix one case in queue_for_group_commit() where killing one thread would
fail to correctly signal the error to the next, causing loss of the
transaction after slave restart.
- Fix leaking of pthreads (and their allocated stack) due to missing
PTHREAD_CREATE_DETACHED attribute.
- Fix how one batch of group-committed transactions wait for the previous
batch before starting to execute themselves. The old code had a very
complex scheduling where the first transaction was handled differently,
with subtle bugs in corner cases. Now each event group is always scheduled
for a new worker (in a round-robin fashion amongst available workers).
Keep a count of how many transactions have started to commit, and wait for
that counter to reach the appropriate value.
- Fix slave stop to wait for all workers to actually complete processing;
before, the wait was for update of last_committed_sub_id, which happens a
bit earlier, and could leave worker threads potentially accessing bits of
the replication state that is no longer valid after slave stop.
- Fix a couple of places where the test suite would kill a thread waiting
inside enter_cond() in connection with debug_sync; debug_sync + kill can
crash in rare cases due to a race with mysys_var_current_mutex in this
case.
- Fix some corner cases where we had enter_cond() but no exit_cond().
- Fix that we could get failure in wait_for_prior_commit() but forget to flag
the error with my_error().
- Fix slave stop (both for normal stop and stop due to error). Now, at stop
we pick a specific safe point (in terms of event groups executed) and make
sure that all event groups before that point are executed to completion,
and that no event group after start executing; this ensures a safe place to
restart replication, even for non-transactional stuff/DDL. In error stop,
make sure that all prior event groups are allowed to execute to completion,
and that any later event groups that have started are rolled back, if
possible. The old code could leave eg. T1 and T3 committed but T2 not, or
it could even leave half a transaction not rolled back in some random
worker, which would cause big problems when that worker was later reused
after slave restart.
- Fix the accounting of amount of events queued for one worker. Before, the
amount was reduced immediately as soon as the events were dequeued (which
happens all at once); this allowed twice the amount of events to be queued
in memory for each single worker, which is not what users would expect.
- Fix that an error set during execution of one event was sometimes not
cleared before executing the next, causing problems with the error
reporting.
- Fix incorrect handling of thd->killed in worker threads.
- Change the default flag value to ON.
- Update the testcases to be run extended_keys=ON:
= trivial test result updates
= If extended_keys setting makes a difference for a testcase, run the testcase
with extended_keys=off. There were only a few such cases
- Update to vcol_select_innodb looks like a worse plan but it will be gone in 10.0.
As part of the fix we don't anymore generate a create table statement when doing a
CREATE TABLE IF NOT EXISTS table_that_exist LiKE temporary_table
if the 'table_that_exist' existed.
This is because it's not self evident if we should generate a create statement
matching the existing table or the temporary_table.
The old code generated a table like the existing table in row based replication and like the temporary table
in statement based replication.
It's better to ensure that both cases works the same way.
mysql-test/suite/rpl/r/rpl_row_create_table.result:
Updated results
(Now we don't anymore CREATE TABLE IF NOT EXISTS LIKE if the table existed)
sql/sql_base.cc:
More DBUG_PRINT
sql/sql_error.cc:
More DBUG_PRINT
sql/sql_table.cc:
Don't generate a create table statement when doing a
CREATE TABLE IF NOT EXISTS table_that_exist like temporary_table if the table existed.
revision-id: monty@askmonty.org-20140211120313-z158i1sdlxxeotgl
committer: Michael Widenius <monty@askmonty.org>
message:
Enable rpl_row_create_table (no reason to keep this disabled anymore)
Still fails (in --ps), no reason to enable it if it is not fixed.
Increase default pointer length for Aria tables to be able to handle big files without having to specify MAX_ROWS
mysql-test/suite/maria/icp.result:
Updated result
mysql-test/suite/maria/maria-preload.result:
More pages are needed with longer pointer length
mysql-test/suite/maria/maria.result:
Added more tests
mysql-test/suite/maria/maria.test:
Added more tests
storage/maria/ma_create.c:
Increase default pointer length for Aria tables to be able to handle big files without having to specify MAX_ROWS
storage/maria/ma_range.c:
Optimize records_in_range() to be more exact
storage/maria/ma_static.c:
Increase default pointer size
storage/maria/ma_test2.c:
Allow a bit larger errors in records_in_range
As a side-effect of purge_relay_logs(), sql_slave_skip_counter
was silently ignored in GTID mode.
But sql_slave_skip_counter in fact is not a good match with GTID.
And it is not really needed either, as users can explicitly set
@@gtid_slave_pos to skip specific GTIDs, in a way that matches
well how GTID replication works.
So with this patch, we give an error on attempts to set
sql_slave_skip_counter when using GTID, with a suggestion to use
gtid_slave_pos instead, if needed.
mysql-test/suite/innodb/r/row_lock.result:
Test case for MDEV-5629
mysql-test/suite/innodb/t/row_lock.test:
Test case for MDEV-5629
sql/filesort.cc:
Don't call unlock_row() in case of errors
MDEV-4984: Implement MASTER_GTID_WAIT() and @@LAST_GTID.
MDEV-4726: Race in mysql-test/suite/rpl/t/rpl_gtid_stop_start.test
MDEV-5636: Deadlock in RESET MASTER
Rewrite the gtid_waiting::wait_for_gtid() function.
The code was rubbish (and buggy). Now the logic is
much clearer.
Also fix a missing slave sync that could cause test failure.
Some GTID test cases were using include/wait_condition.inc with a
condition like SELECT COUNT(*)=4 FROM t1 to wait for the slave to
catch up with the master. This causes races and test failures, as the
changes to the tables become visible at the COMMIT of the SQL thread
(or even before in case of MyISAM), but the changes to
@@gtid_slave_pos only become visible a little bit after the COMMIT.
Now that we have MASTER_GTID_WAIT(), just use that to sync up in a
GTID-friendly way, wrapped in nice include/save_master_gtid.inc and
include/sync_with_master_gtid.inc scripts.
MASTER_GTID_WAIT() is similar to MASTER_POS_WAIT(), but works with a
GTID position rather than an old-style filename/offset.
@@LAST_GTID gives the GTID assigned to the last transaction written
into the binlog.
Together, the two can be used by applications to obtain the GTID of
an update on the master, and then do a MASTER_GTID_WAIT() for that
position on any read slave where it is important to get results that
are caught up with the master at least to the point of the update.
The implementation of MASTER_GTID_WAIT() is implemented in a way
that tries to minimise the performance impact on the SQL threads,
even in the presense of many waiters on single GTID positions (as
from @@LAST_GTID).
