When mysqldump is run to dump the `mysql` system database, it generates
INSERT statements into the table `mysql.gtid_slave_pos`.
After running the backup script
those inserts did not produce the expected gtid state on slave. In
particular the maximum of mysql.gtid_slave_pos.sub_id did not make
into
rpl_global_gtid_slave_state.last_sub_id
an in-memory object that is supposed to match the current state of the
table. And that was regardless of whether --gtid option was specified
or not. Later when the backup recipient server starts as slave
in *non-gtid* mode this desychronization may lead to a duplicate key
error.
This effect is corrected for --gtid mode mysqldump/mariadb-dump only
as the following. The fixes ensure the insert block of the dump
script is followed with a "summing-up" SET @global.gtid_slave_pos
assignment.
For the implemenation part, note a deferred print-out of
SET-gtid_slave_pos and associated comments is prefered over relocating
of the entire blocks if (opt_master,slave_data &&
do_show_master,slave_status) ... because of compatiblity
concern. Namely an error inside do_show_*() is handled in the new code
the same way, as early as, as before.
A regression test can be run in how-to-reproduce mode as well.
One affected mtr test observed.
rpl_mysqldump_slave.result "mismatch" shows now the new deferring print
of SET-gtid_slave_pos policy in action.
There are two problems.
First, replication fails when XA transactions are used where the
slave has replicate_do_db set and the client has touched a different
database when running DML such as inserts. This is because XA
commands are not treated as keywords, and are thereby not exempt
from the replication filter. The effect of this is that during an XA
transaction, if its logged “use db” from the master is filtered out
by the replication filter, then XA END will be ignored, yet its
corresponding XA PREPARE will be executed in an invalid state,
thereby breaking replication.
Second, if the slave replicates an XA transaction which results in
an empty transaction, the XA START through XA PREPARE first phase of
the transaction won’t be binlogged, yet the XA COMMIT will be
binlogged. This will break replication in chain configurations.
The first problem is fixed by treating XA commands in
Query_log_event as keywords, thus allowing them to bypass the
replication filter. Note that Query_log_event::is_trans_keyword() is
changed to accept a new parameter to define its mode, to either
check for XA commands or regular transaction commands, but not both.
In addition, mysqlbinlog is adapted to use this mode so its
--database filter does not remove XA commands from its output.
The second problem fixed by overwriting the XA state in the XID
cache to be XA_ROLLBACK_ONLY, so at commit time, the server knows to
rollback the transaction and skip its binlogging. If the xid cache
is cleared before an XA transaction receives its completion command
(e.g. on server shutdown), then before reporting ER_XAER_NOTA when
the completion command is executed, the filter is first checked if
the database is ignored, and if so, the error is ignored.
Reviewed By:
============
Kristian Nielsen <knielsen@knielsen-hq.org>
Andrei Elkin <andrei.elkin@mariadb.com>
To make this possible, it was also necessary to enhance the mariadb
client with the option --print-query-on-error.
This option can also be very useful when running a batch of queries
through the mariadb client and one wants to find out where things goes
wrong.
TODO: It would be good to enhance mariadb_upgrade to not call the mariadb
client for executing queries but instead do this internally. This
would have made this patch much easier!
Reviewed by: Sergei Golubchik <serg@mariadb.com>
The bug can happens on macOS, if server closes the socket without sending
error packet to client. Closing the socket on server side is legitimate,
and happen e.g when write timeout occurs, perhaps also other situations.
However mysqltest is not prepared to handle mysql_errno 0, and erroneously
thinks connection was successfully established.
The fix/workaround in mysqltest is to treat client failure with
mysql_errno 0 the same as CR_SERVER_LOST (generic client-side
communication error)
The real fix in client library would ensure that mysql_errno is set
on errors.
The strncpy() wrapper that was introduced in
commit 567b681299
is checking whether the output was truncated even in cases
where the caller does not care about it.
Let us introduce a separate function safe_strcpy_truncated() that
indidates whether the output was truncated.
Fix various typos, in comments and DEBUG statements, and code changes
are non-functional.
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.
safety first - tell mariadb client not to execute dangerous
cli commands, they cannot be present in the dump anyway.
wrapping the command in /*!999999 ..... */ guarantees that
if a non-mariadb-cli client loads the dump and sends it to the
server - the server will ignore the command it doesn't understand
mysql --sandbox
disables system (\!), tee (\T), pager with an argument(\P foo), source (\.)
does *not* disable edit (\e). Use EDITOR=/bin/false to disable
or, for example, EDITOR=rnano for something more useful
does *not* disable pager (\P) without an argument. Use
PAGER=cat or, for example PAGER=less LESSSECURE=1 for something
more useful
using a disabled command is an error, which can be ignored with --force
Also, a "sandbox" command (\-) - enables the sandbox mode until EOF
(current file or the session, if interactive)
- ZLIB_LIBRARIES, not ZLIB_LIBRARY
- ZLIB_INCLUDE_DIRS, not ZLIB_INCLUDE_DIR
For building libmariadb, ZLIB_LIBRARY/ZLIB_INCLUDE_DIR are still defined
This workaround will be removed later.
Previously, when running mysqlbinlog without providing a binlog file, it
would print the entire help text, which was very verbose and made it
difficult to identify the actual issue.
Now change the behavior to print a more concise error message instead:
"ERROR: Please provide the log file(s). Run with '--help' for usage instructions."
This makes the error output more user-friendly and easier to understand,
especially when running the tool in scripts or automated processes.
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.
I checked all stack overflow potential problems found with
gcc -Wstack-usage=16384
and
clang -Wframe-larger-than=16384 -no-inline
Fixes:
Added '#pragma clang diagnostic ignored "-Wframe-larger-than="'
to a lot of function to where stack usage large but resonable.
- Added stack check warnings to BUILD scrips when using clang and debug.
Function changed to use malloc instead allocating things on stack:
- read_bootstrap_query() now allocates line_buffer (20000 bytes) with
malloc() instead of using stack. This has a small performance impact
but this is not releant for bootstrap.
- mroonga grn_select() used 65856 bytes on stack. Changed it to use
malloc().
- Wsrep_schema::replay_transaction() and
Wsrep_schema::recover_sr_transactions().
- Connect zipOpen3()
Not fixed:
- mroonga/vendor/groonga/lib/expr.c grn_proc_call() uses
43712 byte on stack. However this is not easy to fix as the stack
used is caused by a lot of code generated by defines.
- Most changes in mroonga/groonga where only adding of pragmas to disable
stack warnings.
- rocksdb/options/options_helper.cc uses 20288 of stack space.
(no reason to fix except to get rid of the compiler warning)
- Causes using alloca() where the allocation size is resonable.
- An issue in libmariadb (reported to connectors).
