show_slave_status_nolock.patch

   1 # name       : show_slave_status_nolock.patch
   2 # introduced : 12
   3 # maintainer : Oleg
   4 #
   5 #!!! notice !!!
   6 # Any small change to this file in the main branch
   7 # should be done or reviewed by the maintainer!
   8 diff -ruN /dev/null b/patch_info/show_slave_status_nolock.patch
   9 --- /dev/null   1970-01-01 00:00:00.000000000 +0000
  10 +++ b/patch_info/show_slave_status_nolock.patch 2011-04-10 11:29:06.000000000 +0400
  11 @@ -0,0 +1,6 @@
  12 +File=show_slave_status_nolock.patch
  13 +Name= SHOW SLAVE STATUS NOLOCK
  14 +Version=1.0
  15 +Author=Percona <info@percona.com>
  16 +License=GPL
  17 +Comment= Implement SHOW SLAVE STATUS without lock (STOP SLAVE lock the same mutex what lock SHOW SLAVE STATUS)
  18 diff -ruN a/sql/lex.h b/sql/lex.h
  19 --- a/sql/lex.h 2011-04-10 11:29:05.000000000 +0400
  20 +++ b/sql/lex.h 2011-04-10 11:29:06.000000000 +0400
  21 @@ -378,6 +378,7 @@
  22    { "NONE",            SYM(NONE_SYM)},
  23    { "NOT",             SYM(NOT_SYM)},
  24    { "NO_WRITE_TO_BINLOG",  SYM(NO_WRITE_TO_BINLOG)},
  25 +  { "NOLOCK",           SYM(NOLOCK_SYM)},
  26    { "NULL",            SYM(NULL_SYM)},
  27    { "NUMERIC",         SYM(NUMERIC_SYM)},
  28    { "NVARCHAR",                SYM(NVARCHAR_SYM)},
  29 diff -ruN a/sql/mysqld.cc b/sql/mysqld.cc
  30 --- a/sql/mysqld.cc     2011-04-10 11:29:05.000000000 +0400
  31 +++ b/sql/mysqld.cc     2011-04-10 11:29:06.000000000 +0400
  32 @@ -3071,6 +3071,7 @@
  33    {"show_relaylog_events", (char*) offsetof(STATUS_VAR, com_stat[(uint) SQLCOM_SHOW_RELAYLOG_EVENTS]), SHOW_LONG_STATUS},
  34    {"show_slave_hosts",     (char*) offsetof(STATUS_VAR, com_stat[(uint) SQLCOM_SHOW_SLAVE_HOSTS]), SHOW_LONG_STATUS},
  35    {"show_slave_status",    (char*) offsetof(STATUS_VAR, com_stat[(uint) SQLCOM_SHOW_SLAVE_STAT]), SHOW_LONG_STATUS},
  36 +  {"show_slave_status_nolock", (char*) offsetof(STATUS_VAR, com_stat[(uint) SQLCOM_SHOW_SLAVE_NOLOCK_STAT]), SHOW_LONG_STATUS},
  37    {"show_status",          (char*) offsetof(STATUS_VAR, com_stat[(uint) SQLCOM_SHOW_STATUS]), SHOW_LONG_STATUS},
  38    {"show_storage_engines", (char*) offsetof(STATUS_VAR, com_stat[(uint) SQLCOM_SHOW_STORAGE_ENGINES]), SHOW_LONG_STATUS},
  39    {"show_table_status",    (char*) offsetof(STATUS_VAR, com_stat[(uint) SQLCOM_SHOW_TABLE_STATUS]), SHOW_LONG_STATUS},
  40 diff -ruN a/sql/sql_lex.h b/sql/sql_lex.h
  41 --- a/sql/sql_lex.h     2011-04-10 11:29:05.000000000 +0400
  42 +++ b/sql/sql_lex.h     2011-04-10 11:29:06.000000000 +0400
  43 @@ -190,6 +190,8 @@
  44    SQLCOM_SHOW_PROFILE, SQLCOM_SHOW_PROFILES,
  45    SQLCOM_SIGNAL, SQLCOM_RESIGNAL,
  46    SQLCOM_SHOW_RELAYLOG_EVENTS,
  47 +  /* SHOW SLAVE STATUS NOLOCK */
  48 +  SQLCOM_SHOW_SLAVE_NOLOCK_STAT,
  49    /*
  50      When a command is added here, be sure it's also added in mysqld.cc
  51      in "struct show_var_st status_vars[]= {" ...
  52 diff -ruN a/sql/sql_parse.cc b/sql/sql_parse.cc
  53 --- a/sql/sql_parse.cc  2011-04-10 11:28:51.000000000 +0400
  54 +++ b/sql/sql_parse.cc  2011-04-10 11:29:06.000000000 +0400
  55 @@ -335,6 +335,7 @@
  56    sql_command_flags[SQLCOM_SHOW_CREATE]=  CF_STATUS_COMMAND;
  57    sql_command_flags[SQLCOM_SHOW_MASTER_STAT]= CF_STATUS_COMMAND;
  58    sql_command_flags[SQLCOM_SHOW_SLAVE_STAT]=  CF_STATUS_COMMAND;
  59 +  sql_command_flags[SQLCOM_SHOW_SLAVE_NOLOCK_STAT]=  CF_STATUS_COMMAND;
  60    sql_command_flags[SQLCOM_SHOW_CREATE_PROC]= CF_STATUS_COMMAND;
  61    sql_command_flags[SQLCOM_SHOW_CREATE_FUNC]= CF_STATUS_COMMAND;
  62    sql_command_flags[SQLCOM_SHOW_CREATE_TRIGGER]=  CF_STATUS_COMMAND;
  63 @@ -2293,12 +2294,16 @@
  64      mysql_mutex_unlock(&LOCK_active_mi);
  65      break;
  66    }
  67 +  case SQLCOM_SHOW_SLAVE_NOLOCK_STAT:
  68    case SQLCOM_SHOW_SLAVE_STAT:
  69    {
  70      /* Accept one of two privileges */
  71      if (check_global_access(thd, SUPER_ACL | REPL_CLIENT_ACL))
  72        goto error;
  73 -    mysql_mutex_lock(&LOCK_active_mi);
  74 +    if(SQLCOM_SHOW_SLAVE_NOLOCK_STAT != lex->sql_command)
  75 +    {
  76 +      mysql_mutex_lock(&LOCK_active_mi);
  77 +    }
  78      if (active_mi != NULL)
  79      {
  80        res = show_master_info(thd, active_mi);
  81 @@ -2309,7 +2314,10 @@
  82                     WARN_NO_MASTER_INFO, ER(WARN_NO_MASTER_INFO));
  83        my_ok(thd);
  84      }
  85 -    mysql_mutex_unlock(&LOCK_active_mi);
  86 +    if(SQLCOM_SHOW_SLAVE_NOLOCK_STAT != lex->sql_command)
  87 +    {
  88 +      mysql_mutex_unlock(&LOCK_active_mi);
  89 +    }
  90      break;
  91    }
  92    case SQLCOM_SHOW_MASTER_STAT:
  93 diff -ruN a/sql/sql_yacc.yy b/sql/sql_yacc.yy
  94 --- a/sql/sql_yacc.yy   2011-04-10 11:29:05.000000000 +0400
  95 +++ b/sql/sql_yacc.yy   2011-04-10 11:29:06.000000000 +0400
  96 @@ -1292,6 +1292,7 @@
  97  %token  STARTS_SYM
  98  %token  START_SYM                     /* SQL-2003-R */
  99  %token  STATUS_SYM
 100 +%token  NOLOCK_SYM                    /* SHOW SLAVE STATUS NOLOCK */
 101  %token  STDDEV_SAMP_SYM               /* SQL-2003-N */
 102  %token  STD_SYM
 103  %token  STOP_SYM
 104 @@ -11082,6 +11083,10 @@
 105            {
 106              Lex->sql_command = SQLCOM_SHOW_SLAVE_STAT;
 107            }
 108 +        | SLAVE STATUS_SYM NOLOCK_SYM
 109 +          {
 110 +           Lex->sql_command = SQLCOM_SHOW_SLAVE_NOLOCK_STAT; //SQLCOM_SHOW_SLAVE_NOLOCK_STAT;
 111 +          }
 112          | QUERY_RESPONSE_TIME_SYM wild_and_where
 113           {
 114  #ifdef HAVE_RESPONSE_TIME_DISTRIBUTION