It is now possible to kill query by query id. KILL syntax was extended to:
KILL [HARD | SOFT] [CONNECTION | QUERY [ID query_id]] [thread_id | USER user_name]
Added QUERY_ID column to INFORMATION_SCHEMA.PROCESSLIST.
Fixed tests affected by this change:
- added PROCESSLIST.QUERY_ID column
- ID is now keyword and is quoted in SHOW CREATE TABLE output
- PFS statement digest is calculated basing on token id
(not token text). Token id has shifted for keywords residing
after ID in keywords array.
ORDER BY does not work
Use "dynamic" row format (instead of "block") for MARIA internal
temporary tables created for cursors.
With "block" row format MARIA may shuffle rows, with "dynamic" row
format records are inserted sequentially (there are no gaps in data
file while we fill temporary tables).
This is needed to preserve row order when scanning materialized cursors.
"SHOW PROCESSLIST"
Analysis:
----------
The problem here is, if one connection changes its
default db and at the same time another connection executes
"SHOW PROCESSLIST", when it wants to read db of the another
connection then there is a chance of accessing the invalid
memory.
The db name stored in THD is not guarded while changing user
DB and while reading the user DB in "SHOW PROCESSLIST".
So, if THD.db is freed by thd "owner" thread and if another
thread executing "SHOW PROCESSLIST" statement tries to read
and copy THD.db at the same time then we may endup in the issue
reported here.
Fix:
----------
Used mutex "LOCK_thd_data" to guard THD.db while freeing it
and while copying it to processlist.
"SHOW PROCESSLIST"
Analysis:
----------
The problem here is, if one connection changes its
default db and at the same time another connection executes
"SHOW PROCESSLIST", when it wants to read db of the another
connection then there is a chance of accessing the invalid
memory.
The db name stored in THD is not guarded while changing user
DB and while reading the user DB in "SHOW PROCESSLIST".
So, if THD.db is freed by thd "owner" thread and if another
thread executing "SHOW PROCESSLIST" statement tries to read
and copy THD.db at the same time then we may endup in the issue
reported here.
Fix:
----------
Used mutex "LOCK_thd_data" to guard THD.db while freeing it
and while copying it to processlist.
* use sql_mode_for_dates() where appropriate.
* always specify an argument for sql_mode_for_dates()
(future-proof. easier to notice and fix if the caller
will start using thd from a local variable or an argument)
Description:
Original fix Bug#11765744 changed mutex to read write lock
to avoid multiple recursive lock acquire operation on
LOCK_status mutex.
On Windows, locking read-write lock recursively is not safe.
Slim read-write locks, which MySQL uses if they are supported by
Windows version, do not support recursion according to their
documentation. For our own implementation of read-write lock,
which is used in cases when Windows version doesn't support SRW,
recursive locking of read-write lock can easily lead to deadlock
if there are concurrent lock requests.
Fix:
This patch reverts the previous fix for bug#11765744 that used
read-write locks. Instead problem of recursive locking for
LOCK_status mutex is solved by tracking recursion level using
counter in THD object and acquiring lock only once when we enter
fill_status() function first time.
Description:
Original fix Bug#11765744 changed mutex to read write lock
to avoid multiple recursive lock acquire operation on
LOCK_status mutex.
On Windows, locking read-write lock recursively is not safe.
Slim read-write locks, which MySQL uses if they are supported by
Windows version, do not support recursion according to their
documentation. For our own implementation of read-write lock,
which is used in cases when Windows version doesn't support SRW,
recursive locking of read-write lock can easily lead to deadlock
if there are concurrent lock requests.
Fix:
This patch reverts the previous fix for bug#11765744 that used
read-write locks. Instead problem of recursive locking for
LOCK_status mutex is solved by tracking recursion level using
counter in THD object and acquiring lock only once when we enter
fill_status() function first time.
Description:
Original fix Bug#11765744 changed mutex to read write lock
to avoid multiple recursive lock acquire operation on
LOCK_status mutex.
On Windows, locking read-write lock recursively is not safe.
Slim read-write locks, which MySQL uses if they are supported by
Windows version, do not support recursion according to their
documentation. For our own implementation of read-write lock,
which is used in cases when Windows version doesn't support SRW,
recursive locking of read-write lock can easily lead to deadlock
if there are concurrent lock requests.
Fix:
This patch reverts the previous fix for bug#11765744 that used
read-write locks. Instead problem of recursive locking for
LOCK_status mutex is solved by tracking recursion level using
counter in THD object and acquiring lock only once when we enter
fill_status() function first time.
Description:
Original fix Bug#11765744 changed mutex to read write lock
to avoid multiple recursive lock acquire operation on
LOCK_status mutex.
On Windows, locking read-write lock recursively is not safe.
Slim read-write locks, which MySQL uses if they are supported by
Windows version, do not support recursion according to their
documentation. For our own implementation of read-write lock,
which is used in cases when Windows version doesn't support SRW,
recursive locking of read-write lock can easily lead to deadlock
if there are concurrent lock requests.
Fix:
This patch reverts the previous fix for bug#11765744 that used
read-write locks. Instead problem of recursive locking for
LOCK_status mutex is solved by tracking recursion level using
counter in THD object and acquiring lock only once when we enter
fill_status() function first time.
includes:
* remove some remnants of "Bug#14521864: MYSQL 5.1 TO 5.5 BUGS PARTITIONING"
* introduce LOCK_share, now LOCK_ha_data is strictly for engines
* rea_create_table() always creates .par file (even in "frm-only" mode)
* fix a 5.6 bug, temp file leak on dummy ALTER TABLE
revno: 4559
committer: Marc Alff <marc.alff@oracle.com>
branch nick: mysql-5.6-bug14741537-v4
timestamp: Thu 2012-11-08 22:40:31 +0100
message:
Bug#14741537 - MYSQL 5.6, GTID AND PERFORMANCE_SCHEMA
Before this fix, statements using performance_schema tables:
- were marked as unsafe for replication,
- did cause warnings during execution,
- were written to the binlog, either in STATEMENT or ROW format.
When using replication with the new GTID feature,
unsafe warnings are elevated to errors,
which prevents to use both the performance_schema and GTID together.
The root cause of the problem is not related to raising warnings/errors
in some special cases, but deeper: statements involving the performance
schema should not even be written to the binary log in the first place,
because the content of the performance schema tables is 'local' to a server
instance, and may differ greatly between nodes in a replication
topology.
In particular, the DBA should be able to configure (INSERT, UPDATE, DELETE)
or flush (TRUNCATE) performance schema tables on one node,
without affecting other nodes.
This fix introduces the concept of a 'non-replicated' or 'local' table,
and adjusts the replication logic to ignore tables that are not replicated
when deciding if or how to log a statement to the binlog.
Note that while this issue was detected using the performance_schema,
other tables are also affected by the same problem.
This fix define as 'local' the following tables, which are then never
replicated:
- performance_schema.*
- mysql.general_log
- mysql.slow_log
- mysql.slave_relay_log_info
- mysql.slave_master_info
- mysql.slave_worker_info
Existing behavior for information_schema.* is unchanged by this fix,
to limit the scope of changes.
Coding wise, this fix implements the following changes:
1)
Performance schema tables are not using any replication flags,
since performance schema tables are not replicated.
2)
In open_table_from_share(),
tables with no replication capabilities (performance_schema.*),
tables with TABLE_CATEGORY_LOG (logs)
and tables with TABLE_CATEGORY_RPL_INFO (replication)
are marked as non replicated, with TABLE::no_replicate
3)
A new THD member, THD::m_binlog_filter_state,
indicate if the current statement is written to the binlog
(normal cases for most statements), or is to be discarded
(because the statements affects non replicated tables).
4)
In THD::decide_logging_format(), the replication logic
is changed to take into account non replicated tables.
Statements that affect only non replicated tables are
executed normally (no warning or errors), but not written
to the binlog.
Statements that affect (i.e., write to) a replicated table
while also using (i.e., reading from or writing to) a non replicated table
are executed normally in MIXED and ROW binlog format,
and cause a new error in STATEMENT binlog format.
THD::decide_logging_format() uses THD::m_binlog_filter_state
to indicate if a statement is to be ignored, when writing to
the binlog.
5)
In THD::binlog_query(), statements marked as ignored
are not written to the binary log.
6)
For row based replication, the existing test for 'table->no_replicate',
has been moved from binlog_log_row() to check_table_binlog_row_based().
Hook in the wait-for-prior-commit logic (not really tested yet).
Clean up some resource maintenance around rpl_group_info (may still be some
smaller issues there though).
Add a ToDo list at the top of rpl_parallel.cc
Implement facility for the commit in one thread to wait for the commit of
another to complete first. The wait is done in a way that does not hinder
that a waiter and a waitee can group commit together with a single fsync()
in both binlog and InnoDB. The wait is done efficiently with respect to
locking.
The patch was originally made to support TaoBao parallel replication with
in-order commit; now it will be adapted to also be used for parallel
replication of group-committed transactions.
A waiter THD registers itself with a prior waitee THD. The waiter will then
complete its commit at the earliest in the same group commit of the waitee
(when using binlog). The wait can also be done explicitly by the waitee.
Users can set different repplication filter rules for each replication connection, in my.cnf or command line.
But the rules set online will not record in master.info, it means if users restart MySQL, these rules will lose.
So if users wantn't their replication filter rules lose, they should write the rules in my.cnf.
Users can set rules by 2 ways:
1. Online SET command, "SET connection_name.replication_filter_settings = rules;".
2. In my.cnf, "connection_name.replication_filter_settings = rules".
If no connection_name in my.cnf, this rule will apply for ALL replication connection.
If no connetion_name in SET statement, this rull will apply for default_connection_name.
