because the name was misleading, it counts not threads, but THDs,
and as THD_count is the only way to increment/decrement it, it
could as well be declared inside THD_count.
This is useful for thing like Item_true and Item_false that we
allocated and initalize once and want to ensure that nothing can
change them
Main changes:
- Memory protection is achived by allocating memory with mmap() and
protect it from write with mprotect()
- init_alloc_root(...,MY_ROOT_USE_MPROTECT) will create a
memroot that one can later use with protect_root() to turn it
read only or turn it back to read-write. All allocations to this
memroot is done with mmap() to ensure page alligned allocations.
- alloc_root() code was rearranged to combine normal and valgrind code.
- init_alloc_root() now changes block size to be power of 2's, to get less
memory fragmentation.
- Changed MEM_ROOT structure to make it smaller. Also renamed
MEM_ROOT m_psi_key to psi_key.
- Moved MY_THREAD_SPECIFIC marker in MEM_ROOT from block size (old hack)
to flags.
- Added global variable my_system_page_size. This is initialized at
startup.
The issue was that we sent two different signals to different threads
after each other. The DEBUG_SYNC functionality cannot handle this (as
the signal is stored in a global variable) and the first one can get
lost.
Fixed by using the same signal for both threads.
This fixed the MySQL bug# 20338 about misuse of double underscore
prefix __WIN__, which was old MySQL's idea of identifying Windows
Replace it by _WIN32 standard symbol for targeting Windows OS
(both 32 and 64 bit)
Not that connect storage engine is not fixed in this patch (must be
fixed in "upstream" branch)
On shutdown, to kill remaining connections, do the same thing that
server does during KILL CONNECTION, i.e thd->awake().
The stripped-down KILL version, that was used prior to this patch
for shutdown, missed the engine specific part (ha_kill_query)
before change test:
strace -fe trace=file -o /tmp/f.strace sql/mysqld --datadir=/tmp/d --log-bin=foo-bin --help --verbose && ls -la /tmp/
...
'mysqladmin variables' instead of 'mysqld --verbose --help'.
total 0
drwxrwxr-x. 2 dan dan 60 May 19 18:05 .
drwxrwxrwt. 27 root root 640 May 19 18:03 ..
-rw-rw----. 1 dan dan 0 May 19 18:05 foo-bin.index
MDEV-25604 Atomic DDL: Binlog event written upon recovery does not
have default database
The purpose of this task is to ensure that ALTER TABLE is atomic even if
the MariaDB server would be killed at any point of the alter table.
This means that either the ALTER TABLE succeeds (including that triggers,
the status tables and the binary log are updated) or things should be
reverted to their original state.
If the server crashes before the new version is fully up to date and
commited, it will revert to the original table and remove all
temporary files and tables.
If the new version is commited, crash recovery will use the new version,
and update triggers, the status tables and the binary log.
The one execption is ALTER TABLE .. RENAME .. where no changes are done
to table definition. This one will work as RENAME and roll back unless
the whole statement completed, including updating the binary log (if
enabled).
Other changes:
- Added handlerton->check_version() function to allow the ddl recovery
code to check, in case of inplace alter table, if the table in the
storage engine is of the new or old version.
- Added handler->table_version() so that an engine can report the current
version of the table. This should be changed each time the table
definition changes.
- Added ha_signal_ddl_recovery_done() and
handlerton::signal_ddl_recovery_done() to inform all handlers when
ddl recovery has been done. (Needed by InnoDB).
- Added handlerton call inplace_alter_table_committed, to signal engine
that ddl_log has been closed for the alter table query.
- Added new handerton flag
HTON_REQUIRES_NOTIFY_TABLEDEF_CHANGED_AFTER_COMMIT to signal when we
should call hton->notify_tabledef_changed() during
mysql_inplace_alter_table. This was required as MyRocks and InnoDB
needed the call at different times.
- Added function server_uuid_value() to be able to generate a temporary
xid when ddl recovery writes the query to the binary log. This is
needed to be able to handle crashes during ddl log recovery.
- Moved freeing of the frm definition to end of mysql_alter_table() to
remove duplicate code and have a common exit strategy.
-------
InnoDB part of atomic ALTER TABLE
(Implemented by Marko Mäkelä)
innodb_check_version(): Compare the saved dict_table_t::def_trx_id
to determine whether an ALTER TABLE operation was committed.
We must correctly recover dict_table_t::def_trx_id for this to work.
Before purge removes any trace of DB_TRX_ID from system tables, it
will make an effort to load the user table into the cache, so that
the dict_table_t::def_trx_id can be recovered.
ha_innobase::table_version(): return garbage, or the trx_id that would
be used for committing an ALTER TABLE operation.
In InnoDB, table names starting with #sql-ib will remain special:
they will be dropped on startup. This may be revisited later in
MDEV-18518 when we implement proper undo logging and rollback
for creating or dropping multiple tables in a transaction.
Table names starting with #sql will retain some special meaning:
dict_table_t::parse_name() will not consider such names for
MDL acquisition, and dict_table_rename_in_cache() will treat such
names specially when handling FOREIGN KEY constraints.
Simplify InnoDB DROP INDEX.
Prevent purge wakeup
To ensure that dict_table_t::def_trx_id will be recovered correctly
in case the server is killed before ddl_log_complete(), we will block
the purge of any history in SYS_TABLES, SYS_INDEXES, SYS_COLUMNS
between ha_innobase::commit_inplace_alter_table(commit=true)
(purge_sys.stop_SYS()) and purge_sys.resume_SYS().
The completion callback purge_sys.resume_SYS() must be between
ddl_log_complete() and MDL release.
--------
MyRocks support for atomic ALTER TABLE
(Implemented by Sergui Petrunia)
Implement these SE API functions:
- ha_rocksdb::table_version()
- hton->check_version = rocksdb_check_versionMyRocks data dictionary
now stores table version for each table.
(Absence of table version record is interpreted as table_version=0,
that is, which means no upgrade changes are needed)
- For inplace alter table of a partitioned table, call the underlying
handlerton when checking if the table is ok. This assumes that the
partition engine commits all changes at once.
- Major rewrite of ddl_log.cc and ddl_log.h
- ddl_log.cc described in the beginning how the recovery works.
- ddl_log.log has unique signature and is dynamic. It's easy to
add more information to the header and other ddl blocks while still
being able to execute old ddl entries.
- IO_SIZE for ddl blocks is now dynamic. Can be changed without affecting
recovery of old logs.
- Code is more modular and is now usable outside of partition handling.
- Renamed log file to dll_recovery.log and added option --log-ddl-recovery
to allow one to specify the path & filename.
- Added ddl_log_entry_phase[], number of phases for each DDL action,
which allowed me to greatly simply set_global_from_ddl_log_entry()
- Changed how strings are stored in log entries, which allows us to
store much more information in a log entry.
- ddl log is now always created at start and deleted on normal shutdown.
This simplices things notable.
- Added probes debug_crash_here() and debug_simulate_error() to simply
crash testing and allow crash after a given number of times a probe
is executed. See comments in debug_sync.cc and rename_table.test for
how this can be used.
- Reverting failed table and view renames is done trough the ddl log.
This ensures that the ddl log is tested also outside of recovery.
- Added helper function 'handler::needs_lower_case_filenames()'
- Extend binary log with Q_XID events. ddl log handling is using this
to check if a ddl log entry was logged to the binary log (if yes,
it will be deleted from the log during ddl_log_close_binlogged_events()
- If a DDL entry fails 3 time, disable it. This is to ensure that if
we have a crash in ddl recovery code the server will not get stuck
in a forever crash-restart-crash loop.
mysqltest.cc changes:
- --die will now replace $variables with their values
- $error will contain the error of the last failed statement
storage engine changes:
- maria_rename() was changed to be more robust against crashes during
rename.
This change removed 68 explict strlen() calls from the code.
The following renames was done to ensure we don't use the old names
when merging code from earlier releases, as using the new variables
for print function could result in crashes:
- charset->csname renamed to charset->cs_name
- charset->name renamed to charset->coll_name
Almost everything where mechanical changes except:
- Changed to use the new Protocol::store(LEX_CSTRING..) when possible
- Changed to use field->store(LEX_CSTRING*, CHARSET_INFO*) when possible
- Changed to use String->append(LEX_CSTRING&) when possible
Other things:
- There where compiler issues with ensuring that all character set names
points to the same string: gcc doesn't allow one to use integer constants
when defining global structures (constant char * pointers works fine).
To get around this, I declared defines for each character set name
length.
- Remove 'dummy_for_valgrind' overrun marker as this doesn't help much.
The element also distorts the sizes of objects a bit, which makes it
harder to calculate gain in object sizes when doing size optimizations.
- Replace usage of thd_get_current_thd() with _current_thd()
- Avoid one extra call indirection when using thd_get_current_thd(), which
is used by Sql_alloc, by replacing it with _current_thd()
This patch changes the main name of 3 byte character set from utf8 to
utf8mb3. New old_mode UTF8_IS_UTF8MB3 is added and set TRUE by default,
so that utf8 would mean utf8mb3. If not set, utf8 would mean utf8mb4.
Part1: Functional changes
Backporting upstream changes.
commit a7e1ef858ee82493dd8ad9a76bc9c22fe3b8c05b
Author: Neha Kumari <neha.n.kumari@oracle.com>
Note:
From the upstream patch only the new option binlog_expire_logs_seconds
specific changes are taken.
* Unlike in the upstream patch 'binlog_expire_logs_seconds' does not
replace the "old" 'expire_logs_days', to preserve backward-compatibility.
* Datatype of 'expire_logs_days' variable is changed to double.
* Default value of 'binlog_expire_logs_seconds=0' similar to
'expire_logs_days'.
* The purge_time can be specified in days with the micro-day precision.
Eg:
expire_logs_days=1 is the same as expire_logs_days=1.000000 to make
binlog_expire_logs_seconds=86400.
binlog_expire_logs_seconds=1 is the same as expire_logs_days=0.000012.
* If binary log is disabled and option 'expire_logs_days' or
'binlog_expire_logs_seconds' used with purge_time > 0 a warning will be
issued.
Merge 'replication_connection_configuration' table.
Replaced following column:
- AUTO_POSITION with USING_GTID
Added new columns for:
- IGNORE_SERVER_IDS
- DO_DOMAIN_IDS
- IGNORE_SERVER_IDS
Removed following columns as they are not part of mariadb replication
connection configuration:
- NETWORK_INTERFACE
- TLS_VERSION
@sql/mysqld.cc
Changed "master-retry-count" default value to 100000.
SI_USER is, however in FreeBSD there are a couple of non-kernel
user signal infomations above SI_KERNEL.
Put a fallback just in case there is nothing available.
This patch makes the following changes around variable wsrep_on:
1) Variable wsrep_on can no longer be updated from a session that has
an active transaction running. The original behavior allowed cases
like this:
BEGIN;
INSERT INTO t1 VALUES (1);
SET SESSION wsrep_on = OFF;
INSERT INTO t1 VALUES (2);
COMMIT;
With regular transactions this would result in no replication
events (not even value 1). With streaming replication it would be
unnecessarily complex to achieve the same behavior. In the above
example, it would be possible for value 1 to be already replicated if
it happened to fill a separate fragment, while value 2 wouldn't.
2) Global variable wsrep_on no longer affects current sessions, only
subsequent ones. This is to avoid a similar case to the above, just
using just by using global wsrep_on instead session wsrep_on:
--connection conn_1
BEGIN;
INSERT INTO t1 VALUES(1);
--connection conn_2
SET GLOBAL wsrep_on = OFF;
--connection conn_1
INSERT INTO t1 VALUES(2);
COMMIT;
The above example results in the transaction to be replicated, as
global wsrep_on will only affect the session wsrep_on of new
connections.
Reviewed-by: Jan Lindström <jan.lindstrom@mariadb.com>
Systemd has a socket activation feature where a mariadb.socket
definition defines the sockets to listen to, and passes those
file descriptors directly to mariadbd to use when a connection
occurs.
The new functionality is utilized when starting as follows:
systemctl start mariadb.socket
The mariadb.socket definition only needs to contain the network
information, ListenStream= directives, the mariadb.service
definition is still used for service instigation.
When mariadbd is started in this way, the socket, port, bind-address
backlog are all assumed to be self contained in the mariadb.socket
definition and as such the mariadb settings and command line
arguments of these network settings are ignored.
See man systemd.socket for how to limit this to specific ports.
Extra ports, those specified with extra_port in socket activation
mode, are those with a FileDescriptorName=extra. These need
to be in a separate service name like mariadb-extra.socket and
these require a Service={mariadb.service} directive to map to the
original service. Extra ports need systemd v227 or greater
(not RHEL/Centos7 - v219) when FileDescriptorName= was added,
otherwise the extra ports are treated like ordinary ports.
The number of sockets isn't limited when using systemd socket activation
(except by operating system limits on file descriptors and a minimal
amount of memory used per file descriptor). The systemd sockets passed
can include any ownership or permissions, including those the
mariadbd process wouldn't normally have the permission to create.
This implementation is compatible with mariadb.service definitions.
Those services started with:
systemctl start mariadb.service
does actually start the mariadb.service and used all the my.cnf
settings of sockets and ports like it previously did.
When we are testing under valgrind, we should be
testing the actual code path used in production code.
This optimization of using shutdown did, in pre-2009,
help purify shutdown quickly. In
b125770aaa this magicly
equated to valgrind, in 2009.
Reviewer: Monty
Problem was that listen_sockets where not properly protected.
Fixed by adding LOCK_start_thread around closing socket loop.
Other things:
- Removed not necessary test in close_socket(). With the current code
'sock' can never be INVALID_SOCKET.
Main reason for this was there was a crash in shutdown of the server
in binlog_encryption.encryption_combo-mix and some other tests because
something in listen_sockets where not initialized. Changing to
Dynamic_array caused things to work.
Other reason for removing std::vector was that it is harder to debug,
and not integrated with DBUG, safemalloc, valgrind or memory
calculation and cause code explosions (extra code generated for each
std::vector type used).
