Instead of returning only one chunk at a time, make
ha_innodb_binlog_reader::read_data() try to read all chunks on the page.
This reduces the number of times each reader has to latch pages in the page
fifo, which contends for a global mutex also shared with the writer.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
This is actually an existing problem in the old binlog implementation, and
this patch is applicable to old binlog also. The problem is that RESET
MASTER can run concurrently with binlog dump threads / connected slaves.
This will remove the binlog from under the feet of the reader, which can
cause all sorts of strange behaviour.
This patch fixes the problem by disallowing to run RESET MASTER when dump
threads (or other RESET MASTER or SHOW BINARY LOGS) are running. An error is
thrown in this case, user must stop slaves and/or kill dump threads to make
the RESET MASTER go through. A slave that connects in the middle of RESET
MASTER will wait for it to complete.
Fix a lot of test cases to kill any lingering dump threads before doing
RESET MASTER, mostly just by sourcing include/kill_binlog_dump_threads.inc.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
This patch makes replication crash-safe with the new binlog implementation,
even when --innodb-flush-log-at-trx-commit=0|2. The point is to not send any
binlog events to the slave until they have become durable on master, thus
avoiding that a slave may replicate a transaction that is lost during master
recovery, diverging the slave from the master.
Keep track of which point in the binlog has been durably synced to disk
(meaning the corresponding LSN has been durably synced to disk in the InnoDB
redo log). Each write to the binlog inserts an entry with offset and
corresponding LSN in a FIFO. Dump threads will first read only up to the
durable point in the binlog. A dump thread will then check the LSN fifo, and
do an InnoDB redo log sync if anything is pending. Then the FIFO is emptied
of any LSNs that have now become durable, and the durable point in the
binlog is updated and reading the binlog can continue.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
Keep track of, for each binlog file, how many open transactions have
out-of-band data starting in that file. Then at the start of each new binlog
file, in the header page, record the file_no of the earliest file that this
file might contain commit records with references back to OOB records in
that earlier file.
Use this in PURGE BINARY LOGS, so that when a dump thread (slave connection)
is active in file number N, and that file (or a later one) may require
looking back in an earlier file number M for out-of-band records, purge will
stop already at file number M. This way, we avoid that purge accidentally
deletes some binlog file that a dump thread would later get an error on
because it needs to read out-of-band data.
This patch also includes placeholder data for a similar facility for XA
references. The actual implementation of support for XA is for later though.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
Mostly various fixes to avoid initializing or creating any data or files for
the legacy binlog.
A possible later refinement could be to sub-class the binlog class
differently for legacy and in-engine binlogs, writing separate virtual
functions for behaviour that differ, extracting common functionality into
sub-methods. This could remove some if (opt_binlog_engine_hton)
conditionals.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
Still ToDo: is to restrict auto-purge so that it does not purge any binlog
file with out-of-band data that might still be needed by a connected slave.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
Enable binlog_in_engine as a default suite.
Fix embedded and Windows build failures.
Use sql_print_(error|warning) over ib::error() and ib::warn().
Use small_vector<> for the innodb_binlog_oob_reader instead of a custom
implementation.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
To find the target position, we first loop backwards over binlog files,
reading the initial GTID state written at the start to find the file to
start in. We then binary search on the differential GTID states written
every --innodb-binlog-state-interval bytes.
This patch does only minimal changes to the dump thread code in sql_repl.cc
to be able to send out binlog data to the client. Some re-factoring/cleanup
should be done in a follow-up patch to more cleanly separate the two code
paths, avoid a lot of if-statements and make the binlog-in-engine code path
free of much of the cruft from the legacy binlog implementation.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
In Log_event::read_log_event(), don't use IO_CACHE::error of the relay log's
IO_CACHE to signal an error back to the caller. When reading the active
relay log, this flag is also being used by the IO thread, and setting it can
randomly cause the IO thread to wrongly detect IO error on writing and
permanently disable the relay log.
This was seen sporadically in test case rpl.rpl_from_mysql80. The read
error set by the SQL thread in the IO_CACHE would be interpreted as a
write error by the IO thread, which would cause it to throw a fatal
error and close the relay log. And this would later cause CHANGE
MASTER to try to purge a closed relay log, resulting in nullptr crash.
SQL thread is not able to parse an event read from the relay log. This
can happen like here when replicating unknown events from a MySQL master,
potentially also for other reasons.
Also fix a mistake in my_b_flush_io_cache() introduced back in 2001
(fa09f2cd7e) where my_b_flush_io_cache() could wrongly return an error set
in IO_CACHE::error, even if the flush operation itself succeeded.
Also fix another sporadic failure in rpl.rpl_from_mysql80 where the outout
of MASTER_POS_WAIT() depended on timing of SQL and IO thread.
Reviewed-by: Monty <monty@mariadb.org>
Reviewed-by: Andrei Elkin <andrei.elkin@mariadb.com>
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
cannot have an assert in Warning_info::push_warning()
because SQL command SIGNAL can set an absolutely arbitrary
message, even an empty one or ending with '\n'
move the assert into push_warning() and my_message_sql().
followup for 9508a44c37
MDEV-29533 Crash when MariaDB is replica of MySQL 8.0
MySQL 8.0 has added the following new events in the MySQL binary log
PARTIAL_UPDATE_ROWS_EVENT
TRANSACTION_PAYLOAD_EVENT
HEARTBEAT_LOG_EVENT_V2
- PARTIAL_UPDATE_ROWS_EVENT is used by MySQL to generate update
statements using JSON_SET, JSON_REPLACE and JSON_REMOVE to make
update of JSON columns more efficient. These events can be
disabled by setting 'binlog-row-value-options=""'
- TRANSACTION_PAYLOAD_EVENT is used by MySQL to signal that a
row event is compressed. It an be disably by setting
'binlog_transaction_compression=0'.
- HEARTBEAT_LOG_EVENT_V2 is written to the binary log many times
per seconds. It can be ignored by the server.
What this patch does:
- If PARTIAL_UPDATE_ROWS_EVENT or TRANSACTION_PAYLOAD_EVENT is found,
the server will stop with an error message of how to disable the
MySQL server to generate such events.
- HEARTBEAT_LOG_EVENT_V2 events are ignored.
- mariadb-binlog will write the name of the new events.
- mariadb-binlog will stop if PARTIAL_UPDATE_ROWS_EVENT or
TRANSACTION_PAYLOAD_EVENT is found, unless --force is given.
- Fixes a crash in mariadb-binlog if a character set unknown to
MariaDB is found. (MDEV-29533)
From Kristian Nielsen:
- Add test case for MySQL 8.0 to MariaDB replication and fixed a
a small typo in post_header_len initialization.
Reviewer: knielsen@mariadb.org
PURGE BINARY LOGS did not always purge binary logs. This commit fixes
some of the issues and adds notifications if a binary log cannot be
purged.
User visible changes:
- 'PURGE BINARY LOG TO log_name' and 'PURGE BINARY LOGS BEFORE date'
worked differently. 'TO' ignored 'slave_connections_needed_for_purge'
while 'BEFORE' did not. Now both versions ignores the
'slave_connections_needed_for_purge variable'.
- 'PURGE BINARY LOG..' commands now returns 'note' if a binary log cannot
be deleted like
Note 1375 Binary log 'master-bin.000004' is not purged because it is
the current active binlog
- Automatic binary log purges, based on date or size, will write a
note to the error log if a binary log matching the size or date
cannot yet be deleted.
- If 'slave_connections_needed_for_purge' is set from a config or
command line, it is set to 0 if Galera is enabled and 1 otherwise
(old default). This ensures that automatic binary log purge works
with Galera as before the addition of
'slave_connections_needed_for_purge'.
If the variable is changed to 0, a warning will be printed to the error
log.
Code changes:
- Added THD argument to several purge_logs related functions that needed
THD.
- Added 'interactive' options to purge_logs functions. This allowed
me to remove testing of sql_command == SQLCOM_PURGE.
- Changed purge_logs_before_date() to first check if log is applicable
before calling can_purge_logs(). This ensures we do not get a
notification for logs that does not match the remove criteria.
- MYSQL_BIN_LOG::can_purge_log() will write notifications to the user
or error log if a log cannot yet be removed.
- log_in_use() will return reason why a binary log cannot be removed.
Changes to keep code consistent:
- Moved checking of binlog_format for Galera to be after Galera is
initialized (The old check never worked). If Galera is enabled
we now change the binlog_format to ROW, with a warning, instead of
aborting the server. If this change happens a warning will be printed to
the error log.
- Print a warning if Galera or FLASHBACK changes the binlog_format
to ROW. Before it was done silently.
Reviewed by: Sergei Golubchik <serg@mariadb.com>,
Kristian Nielsen <knielsen@knielsen-hq.org>
Similar to #2480.
567b681 introduced safe_strcpy() to minimize the use of C with
potentially unsafe memory overflow with strcpy() whose use is
discouraged.
Replace instances of strcpy() with safe_strcpy() where possible, limited
here to files in the `sql/` directory.
All new code of the whole pull request, including one or several files
that are either new files or modified ones, are contributed under the
BSD-new license. I am contributing on behalf of my employer
Amazon Web Services, Inc.
in the $case=2 - it's wrong to kill after the first binlog EOF,
because that might happen between INSERT(4) and INSERT(5).
So, wait for the slave to acknowledge INSERT(5) before killing
the master, that is, both connection threads must pass
repl_semisync_master.wait_after_sync()
binlog_space_limit is a variable in Percona server used to limit the total
size of all binary logs.
This implementation is based on code from Percona server 5.7.
In MariaDB we decided to call the variable max-binlog-total-size to be
similar to max-binlog-size. This makes it easier to find in the output
from 'mariadbd --help --verbose'). MariaDB will also support
binlog_space_limit for compatibility with Percona.
Some internal notes to explain implementation notes:
- When running MariaDB does not delete binary logs that are either
used by slaves or have active xid that are not yet committed.
Some implementation notes:
- max-binlog-total-size is by default 0 (no limit).
- max-binlog-total-size can be changed without server restart.
- Binlog file sizes are checked on startup, or if
max-binlog-total-size is set to a value > 0, not for every log write.
The total size of all binary logs is cached and dynamically updated
when updating the binary log on binary log rotation.
- max-binlog-total-size is checked against existing log files during
serverstart, binlog rotation, FLUSH LOGS, when writing to binary log
or when max-binlog-total-size changes value.
- Option --slave-connections-needed-for-purge with 1 as default added.
This allows one to ensure that we do not delete binary logs if there
is less than 'slave-connections-needed-for-purge' connected.
Without this option max-binlog-total-size would potentially delete
binlogs needed by slaves on server startup or when a slave disconnects
as there are then no connected slaves to protect active binlogs.
- PURGE BINARY LOGS TO ... will be executed as if
slave-connectitons-needed-for-purge would be zero. In other words
it will do the purge even if there is no slaves connected. If there
are connected slaves working on the logs, these will be protected.
- If binary log is on and max-binlog-total_size <> 0 then the status
variable 'Binlog_disk_use' shows the current size of all old binary
logs + the state of the current one.
- Removed test of strcmp(log_file_name, log_info.log_file_name) in
purge_logs_before_date() as this is tested in can_purge_logs()
- To avoid expensive calls of log_in_use() we cache the result for the
last log that is in use by a slave. Future calls to can_purge_logs()
for this binary log will be quickly detected and false will be returned
until a slave starts working on a new log.
- Note that after a binary log rotation caused by max_binlog_size,
the last log will not be purged directly as it is still in use
internally. The next binary log write will purge binlogs if needed.
Reviewer:Kristian Nielsen <knielsen@knielsen-hq.org>
Improve the performance of slave connect using B+-Tree indexes on each binlog
file. The index allows fast lookup of a GTID position to the corresponding
offset in the binlog file, as well as lookup of a position to find the
corresponding GTID position.
This eliminates a costly sequential scan of the starting binlog file
to find the GTID starting position when a slave connects. This is
especially costly if the binlog file is not cached in memory (IO
cost), or if it is encrypted or a lot of slaves connect simultaneously
(CPU cost).
The size of the index files is generally less than 1% of the binlog data, so
not expected to be an issue.
Most of the work writing the index is done as a background task, in
the binlog background thread. This minimises the performance impact on
transaction commit. A simple global mutex is used to protect index
reads and (background) index writes; this is fine as slave connect is
a relatively infrequent operation.
Here are the user-visible options and status variables. The feature is on by
default and is expected to need no tuning or configuration for most users.
binlog_gtid_index
On by default. Can be used to disable the indexes for testing purposes.
binlog_gtid_index_page_size (default 4096)
Page size to use for the binlog GTID index. This is the size of the nodes
in the B+-tree used internally in the index. A very small page-size (64 is
the minimum) will be less efficient, but can be used to stress the
BTree-code during testing.
binlog_gtid_index_span_min (default 65536)
Control sparseness of the binlog GTID index. If set to N, at most one
index record will be added for every N bytes of binlog file written.
This can be used to reduce the number of records in the index, at
the cost only of having to scan a few more events in the binlog file
before finding the target position
Two status variables are available to monitor the use of the GTID indexes:
Binlog_gtid_index_hit
Binlog_gtid_index_miss
The "hit" status increments for each successful lookup in a GTID index.
The "miss" increments when a lookup is not possible. This indicates that the
index file is missing (eg. binlog written by old server version
without GTID index support), or corrupt.
Signed-off-by: Kristian Nielsen <knielsen@knielsen-hq.org>
