database/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-08-08 11:22:35 +03:00
Code Activity

MDEV-29293 MariaDB stuck on starting commit state

Browse Source 
This is a backport from 10.5.

The problem seems to be a deadlock between KILL command execution
and BF abort issued by an applier, where:
* KILL has locked victim's LOCK_thd_kill and LOCK_thd_data.
* Applier has innodb side global lock mutex and victim trx mutex.
* KILL is calling innobase_kill_query, and is blocked by innodb
  global lock mutex.
* Applier is in wsrep_innobase_kill_one_trx and is blocked by
  victim's LOCK_thd_kill.

The fix in this commit removes the TOI replication of KILL command
and makes KILL execution less intrusive operation. Aborting the
victim happens now by using awake_no_mutex() and ha_abort_transaction().
If the KILL happens when the transaction is committing, the
KILL operation is postponed to happen after the statement
has completed in order to avoid KILL to interrupt commit
processing.

Notable changes in this commit:
* wsrep client connections's error state may remain sticky after
  client connection is closed. This error message will then pop
  up for the next client session issuing first SQL statement.
  This problem raised with test galera.galera_bf_kill.
  The fix is to reset wsrep client error state, before a THD is
  reused for next connetion.
* Release THD locks in wsrep_abort_transaction when locking
  innodb mutexes. This guarantees same locking order as with applier
  BF aborting.
* BF abort from MDL was changed to do BF abort on server/wsrep-lib
  side first, and only then do the BF abort on InnoDB side. This
  removes the need to call back from InnoDB for BF aborts which originate
  from MDL and simplifies the locking.
* Removed wsrep_thd_set_wsrep_aborter() from service_wsrep.h.
  The manipulation of the wsrep_aborter can be done solely on
  server side. Moreover, it is now debug only variable and
  could be excluded from optimized builds.
* Remove LOCK_thd_kill from wsrep_thd_LOCK/UNLOCK to allow more
  fine grained locking for SR BF abort which may require locking
  of victim LOCK_thd_kill. Added explicit call for
  wsrep_thd_kill_LOCK/UNLOCK where appropriate.
* Wsrep-lib was updated to version which allows external
  locking for BF abort calls.

Changes to MTR tests:
* Disable galera_bf_abort_group_commit. This test is going to
  be removed (MDEV-30855).
* Record galera_gcache_recover_manytrx as result file was incomplete.
  Trivial change.
* Make galera_create_table_as_select more deterministic:
  Wait until CTAS execution has reached MDL wait for multi-master
  conflict case. Expected error from multi-master conflict is
  ER_QUERY_INTERRUPTED. This is because CTAS does not yet have open
  wsrep transaction when it is waiting for MDL, query gets interrupted
  instead of BF aborted. This should be addressed in separate task.
* A new test galera_kill_group_commit to verify correct behavior
  when KILL is executed while the transaction is committing.

Co-authored-by: Seppo Jaakola <seppo.jaakola@iki.fi>
Co-authored-by: Jan Lindström <jan.lindstrom@galeracluster.com>
Signed-off-by: Julius Goryavsky <julius.goryavsky@mariadb.com>
This commit is contained in:
Teemu Ollakka
2023-04-17 16:04:01 +03:00
committed by Julius Goryavsky
parent 60f0765b58
commit 6966d7fe4b
25 changed files with 591 additions and 263 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
include/mysql/service_wsrep.h
View File

@@ -57,6 +57,7 @@ extern struct wsrep_service_st {
my_bool (*wsrep_on_func)(const MYSQL_THD thd);
bool (*wsrep_prepare_key_for_innodb_func)(MYSQL_THD thd, const unsigned char*, size_t, const unsigned char*, size_t, struct wsrep_buf*, size_t*);
void (*wsrep_thd_LOCK_func)(const MYSQL_THD thd);
int (*wsrep_thd_TRYLOCK_func)(const MYSQL_THD thd);
void (*wsrep_thd_UNLOCK_func)(const MYSQL_THD thd);
const char * (*wsrep_thd_query_func)(const MYSQL_THD thd);
int (*wsrep_thd_retry_counter_func)(const MYSQL_THD thd);
@@ -83,7 +84,6 @@ extern struct wsrep_service_st {
my_bool (*wsrep_get_debug_func)();
void (*wsrep_commit_ordered_func)(MYSQL_THD thd);
my_bool (*wsrep_thd_is_applying_func)(const MYSQL_THD thd);
bool (*wsrep_thd_set_wsrep_aborter_func)(MYSQL_THD bf_thd, MYSQL_THD thd);
void (*wsrep_report_bf_lock_wait_func)(const MYSQL_THD thd,
unsigned long long trx_id);
void (*wsrep_thd_kill_LOCK_func)(const MYSQL_THD thd);
@@ -105,6 +105,7 @@ extern struct wsrep_service_st {
#define wsrep_on(thd) (thd) && WSREP_ON && wsrep_service->wsrep_on_func(thd)
#define wsrep_prepare_key_for_innodb(A,B,C,D,E,F,G) wsrep_service->wsrep_prepare_key_for_innodb_func(A,B,C,D,E,F,G)
#define wsrep_thd_LOCK(T) wsrep_service->wsrep_thd_LOCK_func(T)
#define wsrep_thd_TRYLOCK(T) wsrep_service->wsrep_thd_TRYLOCK_func(T)
#define wsrep_thd_UNLOCK(T) wsrep_service->wsrep_thd_UNLOCK_func(T)
#define wsrep_thd_kill_LOCK(T) wsrep_service->wsrep_thd_kill_LOCK_func(T)
#define wsrep_thd_kill_UNLOCK(T) wsrep_service->wsrep_thd_kill_UNLOCK_func(T)
@@ -130,7 +131,6 @@ extern struct wsrep_service_st {
#define wsrep_get_debug() wsrep_service->wsrep_get_debug_func()
#define wsrep_commit_ordered(T) wsrep_service->wsrep_commit_ordered_func(T)
#define wsrep_thd_is_applying(T) wsrep_service->wsrep_thd_is_applying_func(T)
#define wsrep_thd_set_wsrep_aborter(T) wsrep_service->wsrep_thd_set_wsrep_aborter_func(T1, T2)
#define wsrep_report_bf_lock_wait(T,I) wsrep_service->wsrep_report_bf_lock_wait(T,I)
#define wsrep_thd_set_PA_unsafe(T) wsrep_service->wsrep_thd_set_PA_unsafe_func(T)
#else
@@ -164,6 +164,8 @@ void wsrep_set_data_home_dir(const char *data_dir);
extern "C" my_bool wsrep_on(const MYSQL_THD thd);
/* Lock thd wsrep lock */
extern "C" void wsrep_thd_LOCK(const MYSQL_THD thd);
/* Try thd wsrep lock. Return non-zero if lock could not be taken. */
extern "C" int wsrep_thd_TRYLOCK(const MYSQL_THD thd);
/* Unlock thd wsrep lock */
extern "C" void wsrep_thd_UNLOCK(const MYSQL_THD thd);
@@ -186,8 +188,6 @@ extern "C" my_bool wsrep_thd_is_local(const MYSQL_THD thd);
/* Return true if thd is in high priority mode */
/* todo: rename to is_high_priority() */
extern "C" my_bool wsrep_thd_is_applying(const MYSQL_THD thd);
/* set wsrep_aborter for the target THD */
extern "C" bool wsrep_thd_set_wsrep_aborter(MYSQL_THD bf_thd, MYSQL_THD victim_thd);
/* Return true if thd is in TOI mode */
extern "C" my_bool wsrep_thd_is_toi(const MYSQL_THD thd);
/* Return true if thd is in replicating TOI mode */
@@ -228,7 +228,6 @@ extern "C" my_bool wsrep_get_debug();
extern "C" void wsrep_commit_ordered(MYSQL_THD thd);
extern "C" my_bool wsrep_thd_is_applying(const MYSQL_THD thd);
extern "C" bool wsrep_thd_set_wsrep_aborter(MYSQL_THD bf_thd, MYSQL_THD victim_thd);
extern "C" void wsrep_report_bf_lock_wait(const THD *thd,
unsigned long long trx_id);
/* declare parallel applying unsafety for the THD */