In the AFTER_SYNC case, semi-sync was taking the binlog file name from
the wrong place, so around binlog rotation it could be using the new
name with a position belonging to the previous binlog file name.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
.. file '/var/log/mysql/mariadb-bin.000001' not found in binlog
index, needed for recovery. Aborting.
In Galera cluster, while preparing for rsync/xtrabackup based
SST, the donor node takes an FTWRL followed by (REFRESH_ENGINE_LOG
in rsync based state transfer and) REFRESH_BINARY_LOG. The latter
rotates the binary log and logs Binlog_checkpoint_log_event
corresponding to the penultimate binary log file into the new file.
The checkpoint event for the current file is later logged
synchronously by binlog_background_thread.
Now, since in rsync/xtrabackup based snapshot state transfer methods,
only the last binary log file is transferred to the joiner node; the
file could get transferred even before the checkpoint event for the
same file gets written to it. As a result, the joiner node would fail
to start complaining about the missing binlog file needed for recovery.
In order to fix this, a mechanism has been put in place to make
REFRESH_BINARY_LOG operation wait for Binlog_checkpoint_log_event
to be logged for the current binary log file if the node is part of
a Galera cluster. As further safety, during rsync based state transfer
the donor node now acquires and owns LOCK_log for the duration of file
transfer during SST.
Revert following bug fix:
Bug#20685029: SLAVE IO THREAD SHOULD STOP WHEN DISK IS
FULL
Bug#21753696: MAKE SHOW SLAVE STATUS NON BLOCKING IF IO
THREAD WAITS FOR DISK SPACE
This fix results in a deadlock between slave IO thread
and SQL thread.
(cherry picked from commit e3fea6c6dbb36c6ab21c4ab777224560e9608b53)
FAILURES
Analysis:
=========
Test script is not ensuring that "assert_grep.inc" should be
called only after 'Disk is full' error is written to the
error log.
Test checks for "Queueing master event to the relay log"
state. But this state is set before invoking 'queue_event'.
Actual 'Disk is full' error happens at a very lower level.
It can happen that we might even reset the debug point
before even the actual disk full simulation occurs and the
"Disk is full" message will never appear in the error log.
In order to guarentee that we must have some mechanism where
in after we write "Disk is full" error messge into the error
log we must signal the test to execute SSS and then reset
the debug point. So that test is deterministic.
Fix:
===
Added debug sync point to make script deterministic.
FULL
Bug#21753696: MAKE SHOW SLAVE STATUS NON BLOCKING IF IO
THREAD WAITS FOR DISK SPACE
Problem:
========
Currently SHOW SLAVE STATUS blocks if IO thread waits for
disk space. This makes automation tools verifying
server health block on taking relevant action. Finally this
will create SHOW SLAVE STATUS piles.
Analysis:
=========
SHOW SLAVE STATUS hangs on mi->data_lock if relay log write
is waiting for free disk space while holding mi->data_lock.
mi->data_lock is needed to protect the format description
event (mi->format_description_event) which is accessed by
the clients running FLUSH LOGS and slave IO thread. Note
relay log writes don't need to be protected by
mi->data_lock, LOCK_log is used to protect relay log between
IO and SQL thread (see MYSQL_BIN_LOG::append_event). The
code takes mi->data_lock to protect
mi->format_description_event during relay log rotate which
might get triggered right after relay log write.
Fix:
====
Release the data_lock just for the duration of writing into
relay log.
Made change to ensure the following lock order is maintained
to avoid deadlocks.
data_lock, LOCK_log
data_lock is held during relay log rotations to protect
the description event.
Relax the number-of-XA-engines check on recovery. Allow *more*
engines to be present than absolutely necessary, extra engines
cannot affect ACID guarantees of the recovery process.
As a bonus, 10.0->crash->10.1 upgrade won't complain about
wsrep being a new XA storge engine.
Problem:
=======
rpl_binlog_index.test fails with following valgrind error.
line
Conditional jump or move depends on uninitialised value(s)
at 0x4C2F842: __memcmp_sse4_1 (in /usr/lib64/valgrind/
vgpreload_memcheck-amd64-linux.so)
0x739E39: find_uniq_filename(char*) (log.cc:2212)
0x73A11B: MYSQL_LOG::generate_new_name(char*, char const*)
(log.cc:2492)
0x73A1ED: MYSQL_LOG::init_and_set_log_file_name(char const*,
char const*, enum_log_type, cache_type) (log.cc:2289)
0x73B6F5: MYSQL_BIN_LOG::open(char const*, enum_log_type,
Analysis and fix:
=================
This issue was fixed as part of Bug#20459363 fix in 5.6 and
above. Hence backporting the fix to MySQL-5.5.
- Added --start option to mysqld which don't prints notes to log on startup
This helps to find errors in configure options easier
- Dont write [Note] entries to log after we have abort the server
This makes it easier to find what went wrong
- Don't by default write out Changed limits for max_open_files as this didn't really change from anything the user gave us
- Dont write warnings about not using --explicit_defaults_for_timestamp (we don't have plans do depricate the old behaviour)
--encrypt-binlog and --encrypt-tmp-files used to mean
"encrypt XXX if encryption is available, otherwise don't encrypt",
now they mean "encrypt or fail with an error".
Introduce Log_event_writer() that encapsulates
writing data to an IO_CACHE with automatic checksum calculation.
Now all events properly checksum themselves as needed.
Use Log_event_writer in MYSQL_BIN_LOG::write_cache() instead
of copy-pasting its logic all over.
Later Log_event_writer will also do encryption.
If a transaction T1 needs to wait for a transaction T2, T2's commit will
skip the normal binlog_commit_wait_usec delay, in order not to needlessly
stall throughput.
This works by checking if T2 is already ready to commit. If so, it is woken
up. If not, we set a flag in T2 so that when it gets ready to commit, it
will do so immediately.
But there was a potential race due to insufficient locking, if T2 gets ready
to commit just at the point where T1 does the check. If the race hits, the
wakeup (and early commit) of T2 might be lost.
The race is only theoretical (from code inspection, no known test case), but
seems best to fix it anyway, by properly locking LOCK_prepare_ordered around
the check.
While sql_bin_log=1(0) is meant to control binary logging for the
current session so that the updates to do(not) get logged into the
binary log to be replicated to the async MariaDB slave. The same
should not affect galera replication.
That is, the updates should always get replicated to other galera
nodes regardless of sql_bin_log's value.
Fixed by making sure that the updates are written to binlog cache
irrespective of sql_bin_log.
Added test cases.
Fix was to add a test in Query_log_event::Query_log_event() if we are using
CREATE ... SELECT and in this case use trans cache, like we do on the master.
This avoid using (with doesn't have checksum)
Other things:
- Removed dummy call my_checksum(0L, NULL, 0)
- More DBUG_PRINT
- Cleaned up Log_event::need_checksum() to make it more readable (similar as in MySQL 5.6)
- Renamed variable that was hiding another one in create_table_imp()
field.cc
- Fixed warning about overlapping memory copy (backport from 10.0)
Item_subselect.cc
- Fixed core dump in main.view
- Problem was that thd->lex->current_select->master_unit()->item was not set, which caused crash in maxr_as_dependent
sql/mysqld.cc
- Got error on shutdown as we where freeing mutex before all THD objects was freed
(~THD uses some mutex). Fixed by during shutdown freeing THD inside mutex.
sql/log.cc
- log_space_lock and LOCK_log where locked in inconsistenly. Fixed by not having a log_space_lock around purge_logs.
sql/slave.cc
- Remove unnecessary log_space_lock
- Move cond_broadcast inside lock to ensure we don't miss the signal
Other things:
- Avoid calling init_and_set_log_file_name() when opening binary log.
- Remove newlines early when reading from index file.
- Ensure that reset_logs() will work even if thd is 0 (Can happen on startup)
- Added thd to sart_slave_threads() for better error handling.
