- rel 2; patches updated

[packages/mysql.git] / show_slave_status_nolock.patch

# name       : show_slave_status_nolock.patch
# introduced : 12
# maintainer : Oleg
#
#!!! notice !!!
# Any small change to this file in the main branch
# should be done or reviewed by the maintainer!
--- /dev/null
+++ b/patch_info/show_slave_status_nolock.patch
@@ -0,0 +1,6 @@
+File=show_slave_status_nolock.patch
+Name= SHOW SLAVE STATUS NOLOCK
+Version=1.0
+Author=Percona <info@percona.com>
+License=GPL
+Comment= Implement SHOW SLAVE STATUS without lock (STOP SLAVE lock the same mutex what lock SHOW SLAVE STATUS)
--- a/sql/lex.h
+++ b/sql/lex.h
@@ -378,6 +378,7 @@
   { "NONE",		SYM(NONE_SYM)},
   { "NOT",		SYM(NOT_SYM)},
   { "NO_WRITE_TO_BINLOG",  SYM(NO_WRITE_TO_BINLOG)},
+  { "NOLOCK",           SYM(NOLOCK_SYM)},
   { "NULL",		SYM(NULL_SYM)},
   { "NUMERIC",		SYM(NUMERIC_SYM)},
   { "NVARCHAR",		SYM(NVARCHAR_SYM)},
--- a/sql/mysqld.cc
+++ b/sql/mysqld.cc
@@ -2971,6 +2971,7 @@
   {"show_relaylog_events", (char*) offsetof(STATUS_VAR, com_stat[(uint) SQLCOM_SHOW_RELAYLOG_EVENTS]), SHOW_LONG_STATUS},
   {"show_slave_hosts",     (char*) offsetof(STATUS_VAR, com_stat[(uint) SQLCOM_SHOW_SLAVE_HOSTS]), SHOW_LONG_STATUS},
   {"show_slave_status",    (char*) offsetof(STATUS_VAR, com_stat[(uint) SQLCOM_SHOW_SLAVE_STAT]), SHOW_LONG_STATUS},
+  {"show_slave_status_nolock", (char*) offsetof(STATUS_VAR, com_stat[(uint) SQLCOM_SHOW_SLAVE_NOLOCK_STAT]), SHOW_LONG_STATUS},
   {"show_status",          (char*) offsetof(STATUS_VAR, com_stat[(uint) SQLCOM_SHOW_STATUS]), SHOW_LONG_STATUS},
   {"show_storage_engines", (char*) offsetof(STATUS_VAR, com_stat[(uint) SQLCOM_SHOW_STORAGE_ENGINES]), SHOW_LONG_STATUS},
   {"show_table_status",    (char*) offsetof(STATUS_VAR, com_stat[(uint) SQLCOM_SHOW_TABLE_STATUS]), SHOW_LONG_STATUS},
--- a/sql/sql_lex.h
+++ b/sql/sql_lex.h
@@ -190,6 +190,8 @@
   SQLCOM_SHOW_PROFILE, SQLCOM_SHOW_PROFILES,
   SQLCOM_SIGNAL, SQLCOM_RESIGNAL,
   SQLCOM_SHOW_RELAYLOG_EVENTS, 
+  /* SHOW SLAVE STATUS NOLOCK */
+  SQLCOM_SHOW_SLAVE_NOLOCK_STAT,
   /*
     When a command is added here, be sure it's also added in mysqld.cc
     in "struct show_var_st status_vars[]= {" ...
--- a/sql/sql_parse.cc
+++ b/sql/sql_parse.cc
@@ -336,6 +336,7 @@
   sql_command_flags[SQLCOM_SHOW_CREATE]=  CF_STATUS_COMMAND;
   sql_command_flags[SQLCOM_SHOW_MASTER_STAT]= CF_STATUS_COMMAND;
   sql_command_flags[SQLCOM_SHOW_SLAVE_STAT]=  CF_STATUS_COMMAND;
+  sql_command_flags[SQLCOM_SHOW_SLAVE_NOLOCK_STAT]=  CF_STATUS_COMMAND;
   sql_command_flags[SQLCOM_SHOW_CREATE_PROC]= CF_STATUS_COMMAND;
   sql_command_flags[SQLCOM_SHOW_CREATE_FUNC]= CF_STATUS_COMMAND;
   sql_command_flags[SQLCOM_SHOW_CREATE_TRIGGER]=  CF_STATUS_COMMAND;
@@ -2393,12 +2394,17 @@
     mysql_mutex_unlock(&LOCK_active_mi);
     break;
   }
+  case SQLCOM_SHOW_SLAVE_NOLOCK_STAT:
   case SQLCOM_SHOW_SLAVE_STAT:
   {
     /* Accept one of two privileges */
     if (check_global_access(thd, SUPER_ACL | REPL_CLIENT_ACL))
       goto error;
-    mysql_mutex_lock(&LOCK_active_mi);
+    bool do_lock=SQLCOM_SHOW_SLAVE_NOLOCK_STAT != lex->sql_command;
+    if(do_lock)
+    {
+      mysql_mutex_lock(&LOCK_active_mi);
+    }
     if (active_mi != NULL)
     {
       res = show_master_info(thd, active_mi);
@@ -2409,7 +2415,19 @@
                    WARN_NO_MASTER_INFO, ER(WARN_NO_MASTER_INFO));
       my_ok(thd);
     }
-    mysql_mutex_unlock(&LOCK_active_mi);
+    if(do_lock)
+    {
+      mysql_mutex_unlock(&LOCK_active_mi);
+    }
+    DBUG_EXECUTE_IF("after_show_slave_status",
+                    {
+                      const char act[]=
+                        "now "
+                        "signal signal.after_show_slave_status";
+                      DBUG_ASSERT(opt_debug_sync_timeout > 0);
+                      DBUG_ASSERT(!debug_sync_set_action(current_thd,
+                                                         STRING_WITH_LEN(act)));
+                    };);
     break;
   }
   case SQLCOM_SHOW_MASTER_STAT:
--- a/sql/sql_yacc.yy
+++ b/sql/sql_yacc.yy
@@ -1293,6 +1293,7 @@
 %token  STARTS_SYM
 %token  START_SYM                     /* SQL-2003-R */
 %token  STATUS_SYM
+%token  NOLOCK_SYM                    /* SHOW SLAVE STATUS NOLOCK */
 %token  STDDEV_SAMP_SYM               /* SQL-2003-N */
 %token  STD_SYM
 %token  STOP_SYM
@@ -11111,6 +11112,11 @@
           {
             Lex->sql_command = SQLCOM_SHOW_SLAVE_STAT;
           }
+	/* SHOW SLAVE STATUS NOLOCK */
+        | SLAVE STATUS_SYM NOLOCK_SYM
+          {
+	    Lex->sql_command = SQLCOM_SHOW_SLAVE_NOLOCK_STAT; //SQLCOM_SHOW_SLAVE_NOLOCK_STAT;
+          }
         | QUERY_RESPONSE_TIME_SYM wild_and_where
          {
 #ifdef HAVE_RESPONSE_TIME_DISTRIBUTION
--- /dev/null
+++ b/mysql-test/t/percona_show_slave_status_nolock.test
@@ -0,0 +1,90 @@
+--source include/master-slave.inc
+--source include/have_debug_sync.inc
+--source include/have_binlog_format_statement.inc
+
+call mtr.add_suppression("Slave SQL: Request to stop slave SQL Thread received while applying a group that has non-transactional changes");
+
+--let $rpl_connection_name=slave_lock
+--let $rpl_server_number=2
+--source include/rpl_connect.inc
+
+--let $rpl_connection_name=slave_nolock
+--let $rpl_server_number=2
+--source include/rpl_connect.inc
+
+--let $show_statement= SHOW PROCESSLIST
+--let $field= Info
+
+connection master;
+--echo [master]
+--disable_warnings
+DROP TABLE IF EXISTS t;
+--enable_warnings
+CREATE TABLE t(id INT);
+sync_slave_with_master;
+
+connection slave;
+--echo [slave]
+SET DEBUG_SYNC='RESET';
+SET GLOBAL DEBUG="+d,after_mysql_insert,after_show_slave_status";
+
+connection master;
+--echo [master]
+INSERT INTO t VALUES(0);
+
+connection slave;
+--echo [slave]
+--let $condition= 'INSERT INTO t VALUES(0)'
+--source include/wait_show_condition.inc
+
+--echo check 'SHOW SLAVE STATUS' and 'SHOW SLAVE STATUS NOLOCK' - both should work fine
+--source include/percona_show_slave_status_nolock.inc
+
+connection master;
+--echo [master]
+INSERT INTO t VALUES(1);
+
+connection slave;
+--echo [slave]
+--let $condition= 'INSERT INTO t VALUES(1)'
+--source include/wait_show_condition.inc
+
+--let $rpl_connection_name=slave_stop
+--let $rpl_server_number=2
+--source include/rpl_connect.inc
+
+connection slave_stop;
+--echo [slave_stop]
+send STOP SLAVE;
+
+connection slave;
+--echo [slave]
+--let $condition= 'STOP SLAVE'
+--source include/wait_show_condition.inc
+
+--echo check 'SHOW SLAVE STATUS' and 'SHOW SLAVE STATUS NOLOCK' - just NOLOCK version should works fine
+--source include/percona_show_slave_status_nolock.inc
+
+
+connection slave_stop;
+--echo [slave_stop]
+reap;
+--source include/wait_for_slave_to_stop.inc
+START SLAVE;
+--source include/wait_for_slave_to_start.inc
+
+connection master;
+--echo [master]
+SET DEBUG_SYNC='RESET';
+
+connection slave;
+--echo [slave]
+SET GLOBAL DEBUG='';
+SET DEBUG_SYNC='RESET';
+
+connection master;
+--echo [master]
+DROP TABLE t;
+sync_slave_with_master;
+
+--source include/rpl_end.inc
--- /dev/null
+++ b/mysql-test/r/percona_show_slave_status_nolock.result
@@ -0,0 +1,69 @@
+include/master-slave.inc
+[connection master]
+call mtr.add_suppression("Slave SQL: Request to stop slave SQL Thread received while applying a group that has non-transactional changes");
+include/rpl_connect.inc [creating slave_lock]
+include/rpl_connect.inc [creating slave_nolock]
+[master]
+DROP TABLE IF EXISTS t;
+CREATE TABLE t(id INT);
+[slave]
+SET DEBUG_SYNC='RESET';
+SET GLOBAL DEBUG="+d,after_mysql_insert,after_show_slave_status";
+[master]
+INSERT INTO t VALUES(0);
+[slave]
+check 'SHOW SLAVE STATUS' and 'SHOW SLAVE STATUS NOLOCK' - both should work fine
+
+[slave_lock]
+SHOW SLAVE STATUS;
+SET DEBUG_SYNC='now WAIT_FOR signal.after_show_slave_status TIMEOUT 1';
+SIGNAL after SHOW SLAVE STATUS is 'signal.after_show_slave_status'
+[slave]
+SET DEBUG_SYNC='now SIGNAL signal.empty';
+[slave_nolock]
+SHOW SLAVE STATUS NOLOCK;
+SET DEBUG_SYNC='now WAIT_FOR signal.after_show_slave_status TIMEOUT 1';
+# should be 'signal.after_show_slave_status'
+SIGNAL after SHOW SLAVE STATUS NOLOCK is 'signal.after_show_slave_status'
+[slave]
+SET DEBUG_SYNC='now SIGNAL signal.continue';
+[slave]
+SET DEBUG_SYNC='now SIGNAL signal.empty';
+
+[master]
+INSERT INTO t VALUES(1);
+[slave]
+include/rpl_connect.inc [creating slave_stop]
+[slave_stop]
+STOP SLAVE;
+[slave]
+check 'SHOW SLAVE STATUS' and 'SHOW SLAVE STATUS NOLOCK' - just NOLOCK version should works fine
+
+[slave_lock]
+SHOW SLAVE STATUS;
+SET DEBUG_SYNC='now WAIT_FOR signal.after_show_slave_status TIMEOUT 1';
+SIGNAL after SHOW SLAVE STATUS is 'signal.empty'
+[slave]
+SET DEBUG_SYNC='now SIGNAL signal.empty';
+[slave_nolock]
+SHOW SLAVE STATUS NOLOCK;
+SET DEBUG_SYNC='now WAIT_FOR signal.after_show_slave_status TIMEOUT 1';
+# should be 'signal.after_show_slave_status'
+SIGNAL after SHOW SLAVE STATUS NOLOCK is 'signal.after_show_slave_status'
+[slave]
+SET DEBUG_SYNC='now SIGNAL signal.continue';
+[slave]
+SET DEBUG_SYNC='now SIGNAL signal.empty';
+
+[slave_stop]
+include/wait_for_slave_to_stop.inc
+START SLAVE;
+include/wait_for_slave_to_start.inc
+[master]
+SET DEBUG_SYNC='RESET';
+[slave]
+SET GLOBAL DEBUG='';
+SET DEBUG_SYNC='RESET';
+[master]
+DROP TABLE t;
+include/rpl_end.inc
--- /dev/null
+++ b/mysql-test/include/percona_show_slave_status_nolock.inc
@@ -0,0 +1,56 @@
+--echo
+--disable_result_log
+connection slave_lock;
+--echo [slave_lock]
+send SHOW SLAVE STATUS;
+
+connection slave;
+--let $condition= 'SHOW SLAVE STATUS'
+--source include/wait_show_condition.inc
+
+--disable_warnings
+SET DEBUG_SYNC='now WAIT_FOR signal.after_show_slave_status TIMEOUT 1';
+--enable_warnings
+
+--let current=`SELECT SUBSTR(Variable_value FROM 22) FROM INFORMATION_SCHEMA.SESSION_VARIABLES WHERE Variable_name = 'DEBUG_SYNC'`
+--echo SIGNAL after SHOW SLAVE STATUS is $current
+
+connection slave;
+--echo [slave]
+SET DEBUG_SYNC='now SIGNAL signal.empty';
+
+connection slave_nolock;
+--echo [slave_nolock]
+send SHOW SLAVE STATUS NOLOCK;
+
+connection slave;
+--let $condition= 'SHOW SLAVE STATUS NOLOCK'
+--source include/wait_show_condition.inc
+
+--disable_warnings
+SET DEBUG_SYNC='now WAIT_FOR signal.after_show_slave_status TIMEOUT 1';
+--enable_warnings
+
+--echo # should be 'signal.after_show_slave_status'
+--let current=`SELECT SUBSTR(Variable_value FROM 22) FROM INFORMATION_SCHEMA.SESSION_VARIABLES WHERE Variable_name = 'DEBUG_SYNC'`
+--echo SIGNAL after SHOW SLAVE STATUS NOLOCK is $current
+
+connection slave;
+--echo [slave]
+SET DEBUG_SYNC='now SIGNAL signal.continue';
+
+connection slave_lock;
+--disable_result_log
+reap;
+--enable_result_log
+
+connection slave_nolock;
+--disable_result_log
+reap;
+--enable_result_log
+
+connection slave;
+--echo [slave]
+SET DEBUG_SYNC='now SIGNAL signal.empty';
+--enable_result_log
+--echo
--- a/sql/slave.cc
+++ b/sql/slave.cc
@@ -1816,6 +1816,7 @@
 
   if (mi->host[0])
   {
+    bool do_lock=SQLCOM_SHOW_SLAVE_NOLOCK_STAT != thd->lex->sql_command;
     DBUG_PRINT("info",("host is set: '%s'", mi->host));
     String *packet= &thd->packet;
     protocol->prepare_for_resend();
@@ -1824,9 +1825,15 @@
       slave_running can be accessed without run_lock but not other
       non-volotile members like mi->io_thd, which is guarded by the mutex.
     */
-    mysql_mutex_lock(&mi->run_lock);
+    if (do_lock)
+    {
+      mysql_mutex_lock(&mi->run_lock);
+    }
     protocol->store(mi->io_thd ? mi->io_thd->proc_info : "", &my_charset_bin);
-    mysql_mutex_unlock(&mi->run_lock);
+    if (do_lock)
+    {
+      mysql_mutex_unlock(&mi->run_lock);
+    }
 
     mysql_mutex_lock(&mi->data_lock);
     mysql_mutex_lock(&mi->rli.data_lock);