4437 Nuno Carvalho 2012-09-11
WL#6402: Non blocking show slave status
Introduced a new mutex, info_thd_lock, to increase the locks granularity
on slave workflow, this way there is no need to hold run_lock before
reading info_thd on SHOW SLAVE STATUS.
modified:
sql/mysqld.cc
sql/mysqld.h
sql/rpl_info.cc
sql/rpl_info.h
sql/rpl_info_factory.cc
sql/rpl_mi.cc
sql/rpl_mi.h
sql/rpl_rli.cc
sql/rpl_rli.h
sql/rpl_rli_pdb.cc
sql/rpl_rli_pdb.h
sql/rpl_slave.cc
sql/rpl_slave.h
sql/sql_parse.cc
4436 Nuno Carvalho 2012-09-06
WL#6402: Non blocking show slave status
Updated mysqld--help-win test case result file.
modified:
mysql-test/r/mysqld--help-win.result
=== modified file 'sql/mysqld.cc'
--- a/sql/mysqld.cc revid:nuno.carvalho@stripped
+++ b/sql/mysqld.cc revid:nuno.carvalho@stripped
@@ -9009,9 +9009,9 @@ PSI_mutex_key
key_LOCK_system_variables_hash, key_LOCK_table_share, key_LOCK_thd_data,
key_LOCK_user_conn, key_LOCK_uuid_generator, key_LOG_LOCK_log,
key_master_info_data_lock, key_master_info_run_lock,
- key_master_info_sleep_lock,
+ key_master_info_sleep_lock, key_master_info_thd_lock,
key_mutex_slave_reporting_capability_err_lock, key_relay_log_info_data_lock,
- key_relay_log_info_sleep_lock,
+ key_relay_log_info_sleep_lock, key_relay_log_info_thd_lock,
key_relay_log_info_log_space_lock, key_relay_log_info_run_lock,
key_mutex_slave_parallel_pend_jobs, key_mutex_mts_temp_tables_lock,
key_mutex_slave_parallel_worker,
@@ -9082,9 +9082,11 @@ static PSI_mutex_info all_server_mutexes
{ &key_master_info_data_lock, "Master_info::data_lock", 0},
{ &key_master_info_run_lock, "Master_info::run_lock", 0},
{ &key_master_info_sleep_lock, "Master_info::sleep_lock", 0},
+ { &key_master_info_thd_lock, "Master_info::info_thd_lock", 0},
{ &key_mutex_slave_reporting_capability_err_lock, "Slave_reporting_capability::err_lock", 0},
{ &key_relay_log_info_data_lock, "Relay_log_info::data_lock", 0},
{ &key_relay_log_info_sleep_lock, "Relay_log_info::sleep_lock", 0},
+ { &key_relay_log_info_thd_lock, "Relay_log_info::info_thd_lock", 0},
{ &key_relay_log_info_log_space_lock, "Relay_log_info::log_space_lock", 0},
{ &key_relay_log_info_run_lock, "Relay_log_info::run_lock", 0},
{ &key_mutex_slave_parallel_pend_jobs, "Relay_log_info::pending_jobs_lock", 0},
=== modified file 'sql/mysqld.h'
--- a/sql/mysqld.h revid:nuno.carvalho@stripped
+++ b/sql/mysqld.h revid:nuno.carvalho@stripped
@@ -316,9 +316,9 @@ extern PSI_mutex_key
key_LOCK_table_share, key_LOCK_thd_data,
key_LOCK_user_conn, key_LOCK_uuid_generator, key_LOG_LOCK_log,
key_master_info_data_lock, key_master_info_run_lock,
- key_master_info_sleep_lock,
+ key_master_info_sleep_lock, key_master_info_thd_lock,
key_mutex_slave_reporting_capability_err_lock, key_relay_log_info_data_lock,
- key_relay_log_info_sleep_lock,
+ key_relay_log_info_sleep_lock, key_relay_log_info_thd_lock,
key_relay_log_info_log_space_lock, key_relay_log_info_run_lock,
key_mutex_slave_parallel_pend_jobs, key_mutex_mts_temp_tables_lock,
key_mutex_slave_parallel_worker,
=== modified file 'sql/rpl_info.cc'
--- a/sql/rpl_info.cc revid:nuno.carvalho@stripped
+++ b/sql/rpl_info.cc revid:nuno.carvalho@stripped
@@ -22,6 +22,7 @@ Rpl_info::Rpl_info(const char* type
,PSI_mutex_key *param_key_info_run_lock,
PSI_mutex_key *param_key_info_data_lock,
PSI_mutex_key *param_key_info_sleep_lock,
+ PSI_mutex_key *param_key_info_thd_lock,
PSI_mutex_key *param_key_info_data_cond,
PSI_mutex_key *param_key_info_start_cond,
PSI_mutex_key *param_key_info_stop_cond,
@@ -34,6 +35,7 @@ Rpl_info::Rpl_info(const char* type
key_info_run_lock(param_key_info_run_lock),
key_info_data_lock(param_key_info_data_lock),
key_info_sleep_lock(param_key_info_sleep_lock),
+ key_info_thd_lock(param_key_info_thd_lock),
key_info_data_cond(param_key_info_data_cond),
key_info_start_cond(param_key_info_start_cond),
key_info_stop_cond(param_key_info_stop_cond),
@@ -50,6 +52,8 @@ Rpl_info::Rpl_info(const char* type
&data_lock, MY_MUTEX_INIT_FAST);
mysql_mutex_init(*key_info_sleep_lock,
&sleep_lock, MY_MUTEX_INIT_FAST);
+ mysql_mutex_init(*key_info_thd_lock,
+ &info_thd_lock, MY_MUTEX_INIT_FAST);
mysql_cond_init(*key_info_data_cond, &data_cond, NULL);
mysql_cond_init(*key_info_start_cond, &start_cond, NULL);
mysql_cond_init(*key_info_stop_cond, &stop_cond, NULL);
@@ -58,6 +62,7 @@ Rpl_info::Rpl_info(const char* type
mysql_mutex_init(NULL, &run_lock, MY_MUTEX_INIT_FAST);
mysql_mutex_init(NULL, &data_lock, MY_MUTEX_INIT_FAST);
mysql_mutex_init(NULL, &sleep_lock, MY_MUTEX_INIT_FAST);
+ mysql_mutex_init(NULL, &info_thd_lock, MY_MUTEX_INIT_FAST);
mysql_cond_init(NULL, &data_cond, NULL);
mysql_cond_init(NULL, &start_cond, NULL);
mysql_cond_init(NULL, &stop_cond, NULL);
@@ -72,6 +77,7 @@ Rpl_info::~Rpl_info()
mysql_mutex_destroy(&run_lock);
mysql_mutex_destroy(&data_lock);
mysql_mutex_destroy(&sleep_lock);
+ mysql_mutex_destroy(&info_thd_lock);
mysql_cond_destroy(&data_cond);
mysql_cond_destroy(&start_cond);
mysql_cond_destroy(&stop_cond);
=== modified file 'sql/rpl_info.h'
--- a/sql/rpl_info.h revid:nuno.carvalho@stripped
+++ b/sql/rpl_info.h revid:nuno.carvalho@stripped
@@ -30,8 +30,13 @@ public:
standard lock acquisition order to avoid deadlocks:
run_lock, data_lock, relay_log.LOCK_log, relay_log.LOCK_index
run_lock, sleep_lock
+
+ info_thd_lock is to protect operations on info_thd:
+ - before *reading* info_thd we must hold *either* info_thd_lock or
+ run_lock;
+ - before *writing* we must hold *both* info_thd_lock and run_lock.
*/
- mysql_mutex_t data_lock, run_lock, sleep_lock;
+ mysql_mutex_t data_lock, run_lock, sleep_lock, info_thd_lock;
/*
start_cond is broadcast when SQL thread is started
stop_cond - when stopped
@@ -41,7 +46,8 @@ public:
mysql_cond_t data_cond, start_cond, stop_cond, sleep_cond;
#ifdef HAVE_PSI_INTERFACE
- PSI_mutex_key *key_info_run_lock, *key_info_data_lock, *key_info_sleep_lock;
+ PSI_mutex_key *key_info_run_lock, *key_info_data_lock, *key_info_sleep_lock,
+ *key_info_thd_lock;
PSI_mutex_key *key_info_data_cond, *key_info_start_cond, *key_info_stop_cond,
*key_info_sleep_cond;
@@ -140,6 +146,7 @@ protected:
,PSI_mutex_key *param_key_info_run_lock,
PSI_mutex_key *param_key_info_data_lock,
PSI_mutex_key *param_key_info_sleep_lock,
+ PSI_mutex_key *param_key_info_thd_lock,
PSI_mutex_key *param_key_info_data_cond,
PSI_mutex_key *param_key_info_start_cond,
PSI_mutex_key *param_key_info_stop_cond,
=== modified file 'sql/rpl_info_factory.cc'
--- a/sql/rpl_info_factory.cc revid:nuno.carvalho@stripped
+++ b/sql/rpl_info_factory.cc revid:nuno.carvalho@stripped
@@ -99,6 +99,7 @@ Master_info *Rpl_info_factory::create_mi
&key_master_info_run_lock,
&key_master_info_data_lock,
&key_master_info_sleep_lock,
+ &key_master_info_thd_lock,
&key_master_info_data_cond,
&key_master_info_start_cond,
&key_master_info_stop_cond,
@@ -217,6 +218,7 @@ Relay_log_info *Rpl_info_factory::create
,&key_relay_log_info_run_lock,
&key_relay_log_info_data_lock,
&key_relay_log_info_sleep_lock,
+ &key_relay_log_info_thd_lock,
&key_relay_log_info_data_cond,
&key_relay_log_info_start_cond,
&key_relay_log_info_stop_cond,
@@ -382,6 +384,7 @@ Slave_worker *Rpl_info_factory::create_w
,&key_relay_log_info_run_lock,
&key_relay_log_info_data_lock,
&key_relay_log_info_sleep_lock,
+ &key_relay_log_info_thd_lock,
&key_relay_log_info_data_cond,
&key_relay_log_info_start_cond,
&key_relay_log_info_stop_cond,
=== modified file 'sql/rpl_mi.cc'
--- a/sql/rpl_mi.cc revid:nuno.carvalho@stripped
+++ b/sql/rpl_mi.cc revid:nuno.carvalho@stripped
@@ -96,6 +96,7 @@ Master_info::Master_info(
PSI_mutex_key *param_key_info_run_lock,
PSI_mutex_key *param_key_info_data_lock,
PSI_mutex_key *param_key_info_sleep_lock,
+ PSI_mutex_key *param_key_info_thd_lock,
PSI_mutex_key *param_key_info_data_cond,
PSI_mutex_key *param_key_info_start_cond,
PSI_mutex_key *param_key_info_stop_cond,
@@ -106,7 +107,7 @@ Master_info::Master_info(
:Rpl_info("I/O"
#ifdef HAVE_PSI_INTERFACE
,param_key_info_run_lock, param_key_info_data_lock,
- param_key_info_sleep_lock,
+ param_key_info_sleep_lock, param_key_info_thd_lock,
param_key_info_data_cond, param_key_info_start_cond,
param_key_info_stop_cond, param_key_info_sleep_cond
#endif
=== modified file 'sql/rpl_mi.h'
--- a/sql/rpl_mi.h revid:nuno.carvalho@stripped
+++ b/sql/rpl_mi.h revid:nuno.carvalho@stripped
@@ -370,6 +370,7 @@ private:
PSI_mutex_key *param_key_info_run_lock,
PSI_mutex_key *param_key_info_data_lock,
PSI_mutex_key *param_key_info_sleep_lock,
+ PSI_mutex_key *param_key_info_thd_lock,
PSI_mutex_key *param_key_info_data_cond,
PSI_mutex_key *param_key_info_start_cond,
PSI_mutex_key *param_key_info_stop_cond,
=== modified file 'sql/rpl_rli.cc'
--- a/sql/rpl_rli.cc revid:nuno.carvalho@stripped
+++ b/sql/rpl_rli.cc revid:nuno.carvalho@stripped
@@ -56,6 +56,7 @@ Relay_log_info::Relay_log_info(bool is_s
,PSI_mutex_key *param_key_info_run_lock,
PSI_mutex_key *param_key_info_data_lock,
PSI_mutex_key *param_key_info_sleep_lock,
+ PSI_mutex_key *param_key_info_thd_lock,
PSI_mutex_key *param_key_info_data_cond,
PSI_mutex_key *param_key_info_start_cond,
PSI_mutex_key *param_key_info_stop_cond,
@@ -66,7 +67,7 @@ Relay_log_info::Relay_log_info(bool is_s
:Rpl_info("SQL"
#ifdef HAVE_PSI_INTERFACE
,param_key_info_run_lock, param_key_info_data_lock,
- param_key_info_sleep_lock,
+ param_key_info_sleep_lock, param_key_info_thd_lock,
param_key_info_data_cond, param_key_info_start_cond,
param_key_info_stop_cond, param_key_info_sleep_cond
#endif
=== modified file 'sql/rpl_rli.h'
--- a/sql/rpl_rli.h revid:nuno.carvalho@stripped
+++ b/sql/rpl_rli.h revid:nuno.carvalho@stripped
@@ -834,6 +834,7 @@ public:
,PSI_mutex_key *param_key_info_run_lock,
PSI_mutex_key *param_key_info_data_lock,
PSI_mutex_key *param_key_info_sleep_lock,
+ PSI_mutex_key *param_key_info_thd_lock,
PSI_mutex_key *param_key_info_data_cond,
PSI_mutex_key *param_key_info_start_cond,
PSI_mutex_key *param_key_info_stop_cond,
=== modified file 'sql/rpl_rli_pdb.cc'
--- a/sql/rpl_rli_pdb.cc revid:nuno.carvalho@stripped
+++ b/sql/rpl_rli_pdb.cc revid:nuno.carvalho@stripped
@@ -69,6 +69,7 @@ Slave_worker::Slave_worker(Relay_log_inf
,PSI_mutex_key *param_key_info_run_lock,
PSI_mutex_key *param_key_info_data_lock,
PSI_mutex_key *param_key_info_sleep_lock,
+ PSI_mutex_key *param_key_info_thd_lock,
PSI_mutex_key *param_key_info_data_cond,
PSI_mutex_key *param_key_info_start_cond,
PSI_mutex_key *param_key_info_stop_cond,
@@ -79,7 +80,7 @@ Slave_worker::Slave_worker(Relay_log_inf
: Relay_log_info(FALSE
#ifdef HAVE_PSI_INTERFACE
,param_key_info_run_lock, param_key_info_data_lock,
- param_key_info_sleep_lock,
+ param_key_info_sleep_lock, param_key_info_thd_lock,
param_key_info_data_cond, param_key_info_start_cond,
param_key_info_stop_cond, param_key_info_sleep_cond
#endif
@@ -113,7 +114,9 @@ Slave_worker::~Slave_worker()
delete_dynamic(&curr_group_exec_parts);
mysql_mutex_destroy(&jobs_lock);
mysql_cond_destroy(&jobs_cond);
+ mysql_mutex_lock(&info_thd_lock);
info_thd= NULL;
+ mysql_mutex_unlock(&info_thd_lock);
set_rli_description_event(NULL);
}
=== modified file 'sql/rpl_rli_pdb.h'
--- a/sql/rpl_rli_pdb.h revid:nuno.carvalho@stripped
+++ b/sql/rpl_rli_pdb.h revid:nuno.carvalho@stripped
@@ -287,6 +287,7 @@ public:
,PSI_mutex_key *param_key_info_run_lock,
PSI_mutex_key *param_key_info_data_lock,
PSI_mutex_key *param_key_info_sleep_lock,
+ PSI_mutex_key *param_key_info_thd_lock,
PSI_mutex_key *param_key_info_data_cond,
PSI_mutex_key *param_key_info_start_cond,
PSI_mutex_key *param_key_info_stop_cond,
=== modified file 'sql/rpl_slave.cc'
--- a/sql/rpl_slave.cc revid:nuno.carvalho@stripped
+++ b/sql/rpl_slave.cc revid:nuno.carvalho@stripped
@@ -2412,12 +2412,10 @@ int register_slave_on_master(MYSQL* mysq
@param mi Pointer to Master_info object for the IO thread.
- @param hold_run_locks Indicates if command must hold run_lock mutexes.
-
@retval FALSE success
@retval TRUE failure
*/
-bool show_slave_status(THD* thd, Master_info* mi, bool hold_run_locks)
+bool show_slave_status(THD* thd, Master_info* mi)
{
// TODO: fix this for multi-master
List<Item> field_list;
@@ -2545,27 +2543,16 @@ bool show_slave_status(THD* thd, Master_
/*
slave_running can be accessed without run_lock but not other
- non-volotile members like mi->info_thd, which is guarded by the mutex.
-
- "SHOW SLAVE STATUS NONBLOCKING" do not holds LOCK_active_mi,
- mi->run_lock and mi->rli->run_lock mutexes, slave status will be
- returned even when slave is being stopped what may cause
- inconsistent results.
- This nonblocking command is intended to be executed by monitoring
- tools on which is more important to do not block requests then have
- the last updated status.
+ non-volotile members like mi->info_thd or rli->info_thd, for
+ them either info_thd_lock or run_lock hold is required.
*/
- if (hold_run_locks)
- mysql_mutex_lock(&mi->run_lock);
+ mysql_mutex_lock(&mi->info_thd_lock);
protocol->store(mi->info_thd ? mi->info_thd->get_proc_info() : "", &my_charset_bin);
- if (hold_run_locks)
- mysql_mutex_unlock(&mi->run_lock);
+ mysql_mutex_unlock(&mi->info_thd_lock);
- if (hold_run_locks)
- mysql_mutex_lock(&mi->rli->run_lock);
+ mysql_mutex_lock(&mi->rli->info_thd_lock);
slave_sql_running_state= const_cast<char *>(mi->rli->info_thd ? mi->rli->info_thd->get_proc_info() : "");
- if (hold_run_locks)
- mysql_mutex_unlock(&mi->rli->run_lock);
+ mysql_mutex_unlock(&mi->rli->info_thd_lock);
mysql_mutex_lock(&mi->data_lock);
mysql_mutex_lock(&mi->rli->data_lock);
@@ -4321,7 +4308,9 @@ err:
mi->abort_slave= 0;
mi->slave_running= 0;
+ mysql_mutex_lock(&mi->info_thd_lock);
mi->info_thd= 0;
+ mysql_mutex_unlock(&mi->info_thd_lock);
/*
Note: the order of the two following calls (first broadcast, then unlock)
is important. Otherwise a killer_thread can execute between the calls and
@@ -4407,7 +4396,9 @@ pthread_handler_t handle_slave_worker(vo
sql_print_error("Failed during slave worker initialization");
goto err;
}
+ mysql_mutex_lock(&w->info_thd_lock);
w->info_thd= thd;
+ mysql_mutex_unlock(&w->info_thd_lock);
thd->thread_stack = (char*)&thd;
pthread_detach_this_thread();
@@ -5305,7 +5296,9 @@ pthread_handler_t handle_slave_sql(void
thd = new THD; // note that contructor of THD uses DBUG_ !
thd->thread_stack = (char*)&thd; // remember where our stack is
+ mysql_mutex_lock(&rli->info_thd_lock);
rli->info_thd= thd;
+ mysql_mutex_unlock(&rli->info_thd_lock);
/* Inform waiting threads that slave has started */
rli->slave_run_id++;
@@ -5644,7 +5637,9 @@ llstr(rli->get_group_master_log_pos(), l
net_end(&thd->net); // destructor will not free it, because we are weird
DBUG_ASSERT(rli->info_thd == thd);
THD_CHECK_SENTRY(thd);
+ mysql_mutex_lock(&rli->info_thd_lock);
rli->info_thd= 0;
+ mysql_mutex_unlock(&rli->info_thd_lock);
set_thd_in_use_temporary_tables(rli); // (re)set info_thd in use for saved temp tables
thd->release_resources();
=== modified file 'sql/rpl_slave.h'
--- a/sql/rpl_slave.h revid:nuno.carvalho@stripped
+++ b/sql/rpl_slave.h revid:nuno.carvalho@stripped
@@ -308,7 +308,7 @@ int start_slave_thread(
int fetch_master_table(THD* thd, const char* db_name, const char* table_name,
Master_info* mi, MYSQL* mysql, bool overwrite);
-bool show_slave_status(THD* thd, Master_info* mi, bool hold_run_locks= true);
+bool show_slave_status(THD* thd, Master_info* mi);
bool rpl_master_has_bug(const Relay_log_info *rli, uint bug_id, bool report,
bool (*pred)(const void *), const void *param);
bool rpl_master_erroneous_autoinc(THD* thd);
=== modified file 'sql/sql_parse.cc'
--- a/sql/sql_parse.cc revid:nuno.carvalho@stripped
+++ b/sql/sql_parse.cc revid:nuno.carvalho@stripped
@@ -2733,7 +2733,7 @@ case SQLCOM_PREPARE:
/* Accept one of two privileges */
if (check_global_access(thd, SUPER_ACL | REPL_CLIENT_ACL))
goto error;
- res= show_slave_status(thd, active_mi, false);
+ res= show_slave_status(thd, active_mi);
break;
}
case SQLCOM_SHOW_MASTER_STAT:
No bundle (reason: useless for push emails).
| Thread |
|---|
| • bzr push into mysql-trunk-wl6402 branch (nuno.carvalho:4436 to 4437) WL#6402 | Nuno Carvalho | 11 Sep |
