From: Jonas Oreland
Date: February 9 2011 7:57am
Subject: Re: bzr commit into mysql-5.5-telco-7.0 branch (magnus.blaudd:3195)
List-Archive: http://lists.mysql.com/commits/130801
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super...


On 02/09/11 08:58, Magnus Blćudd wrote:
> #At file:///home/msvensson/mysql/5.5-telco-7.0-run-query/ based on revid:magnus.blaudd@stripped
> 
>  3195 Magnus BlÄudd	2011-02-09
>       ndb
>        - Straigthen up the interface of ndb_binlog allowing to hide its internals
>        -- Rename ndbcluster_setup_binlog_table_shares to ndb_binlog_setup and
>           make it return true or false for sucess/fail
>        -- Make "ndb_binlog_tables_inited" variable local to ha_ndbcluster_binlog
>        -- Add function ndb_binlog_is_read_only() which return false as long as the
>           binlog is not ready and we only allow to open tables in read only mode.
>        -- Make "ndb_binlog_is_ready" variable local to ha_ndbcluster_binlog
>        -- Remove the first call to ndb_binlog_setup, calling it once
>           every second until it succeeds and regularly thereafter should be enough.
> 
>     modified:
>       sql/ha_ndbcluster.cc
>       sql/ha_ndbcluster_binlog.cc
>       sql/ha_ndbcluster_binlog.h
> === modified file 'sql/ha_ndbcluster.cc'
> --- a/sql/ha_ndbcluster.cc	2011-02-09 07:28:54 +0000
> +++ b/sql/ha_ndbcluster.cc	2011-02-09 07:58:07 +0000
> @@ -9696,8 +9696,7 @@ int ha_ndbcluster::open(const char *name
>      local_close(thd, TRUE);
>      DBUG_RETURN(res);
>    }
> -  if (!ndb_binlog_tables_inited ||
> -      (ndb_binlog_running && !ndb_binlog_is_ready))
> +  if (ndb_binlog_is_read_only())
>    {
>      table->db_stat|= HA_READ_ONLY;
>      sql_print_information("table '%s' opened read only", name);
> @@ -13125,8 +13124,6 @@ pthread_handler_t ndb_util_thread_func(v
>  
>    if (opt_ndb_extra_logging && ndb_binlog_running)
>      sql_print_information("NDB Binlog: Ndb tables initially read only.");
> -  /* create tables needed by the replication */
> -  ndbcluster_setup_binlog_table_shares(thd);
>  
>    set_timespec(abstime, 0);
>    for (;;)
> @@ -13145,23 +13142,28 @@ pthread_handler_t ndb_util_thread_func(v
>  #endif
>  
>      /*
> -      Check that the ndb_apply_status_share and ndb_schema_share 
> -      have been created.
> -      If not try to create it
> +      Check if the Ndb object in thd_ndb is still valid(it will be
> +      invalid if connection to cluster has been lost) and recycle
> +      it if necessary.
>      */
>      if (!check_ndb_in_thd(thd, false))
>      {
>        set_timespec(abstime, 1);
>        continue;
>      }
> -    if (!ndb_binlog_tables_inited)
> +
> +    /*
> +      Regularly give the ndb_binlog component chance to set it self up
> +      i.e at first start it needs to create the ndb_* system tables
> +      and setup event operations on those. In case of lost connection
> +      to cluster, the ndb_* system tables are hopefully still there
> +      but the event operations need to be recreated.
> +    */
> +    if (!ndb_binlog_setup(thd))
>      {
> -      ndbcluster_setup_binlog_table_shares(thd);
> -      if (!ndb_binlog_tables_inited)
> -      {
> -        set_timespec(abstime, 1);
> -        continue;
> -      }
> +      /* Failed to setup binlog, try again in 1 second */
> +      set_timespec(abstime, 1);
> +      continue;
>      }
>  
>      if (opt_ndb_cache_check_time == 0)
> 
> === modified file 'sql/ha_ndbcluster_binlog.cc'
> --- a/sql/ha_ndbcluster_binlog.cc	2011-02-08 10:11:09 +0000
> +++ b/sql/ha_ndbcluster_binlog.cc	2011-02-09 07:58:07 +0000
> @@ -74,8 +74,29 @@ static int ndb_binlog_thread_running= 0;
>    FALSE if not
>  */
>  my_bool ndb_binlog_running= FALSE;
> -my_bool ndb_binlog_tables_inited= FALSE;
> -my_bool ndb_binlog_is_ready= FALSE;
> +static my_bool ndb_binlog_tables_inited= FALSE;
> +static my_bool ndb_binlog_is_ready= FALSE;
> +
> +bool
> +ndb_binlog_is_read_only(void)
> +{
> +  if(!ndb_binlog_tables_inited)
> +  {
> +    /* the ndb_* system tables not setup yet */
> +    return true;
> +  }
> +
> +  if (ndb_binlog_running && !ndb_binlog_is_ready)
> +  {
> +    /*
> +      The binlog thread is supposed to write to binlog
> +      but not ready (still initializing or has lost connection)
> +    */
> +    return true;
> +  }
> +  return false;
> +}
> +
>  /*
>    Global reference to the ndb injector thread THD oject
>  
> @@ -1553,11 +1574,15 @@ static int ndbcluster_find_all_databases
>    }
>  }
>  
> -int ndbcluster_setup_binlog_table_shares(THD *thd)
> +bool
> +ndb_binlog_setup(THD *thd)
>  {
> +  if (ndb_binlog_tables_inited)
> +    return true; // Already setup -> OK
> +
>    Ndbcluster_global_schema_lock_guard global_schema_lock_guard(thd);
>    if (global_schema_lock_guard.lock())
> -    return 1;
> +    return false;
>    if (!ndb_schema_share &&
>        ndbcluster_check_ndb_schema_share() == 0)
>    {
> @@ -1567,7 +1592,7 @@ int ndbcluster_setup_binlog_table_shares
>        ndbcluster_create_schema_table(thd);
>        // always make sure we create the 'schema' first
>        if (!ndb_schema_share)
> -        return 1;
> +        return false;
>      }
>    }
>    if (!ndb_apply_status_share &&
> @@ -1578,13 +1603,13 @@ int ndbcluster_setup_binlog_table_shares
>      {
>        ndbcluster_create_ndb_apply_status_table(thd);
>        if (!ndb_apply_status_share)
> -        return 1;
> +        return false;
>      }
>    }
>  
>    if (ndbcluster_find_all_databases(thd))
>    {
> -    return 1;
> +    return false;
>    }
>  
>    if (!ndbcluster_find_all_files(thd))
> @@ -1605,8 +1630,10 @@ int ndbcluster_setup_binlog_table_shares
>      }
>      /* Signal injector thread that all is setup */
>      pthread_cond_signal(&injector_cond);
> +
> +    return true; // Setup completed -> OK
>    }
> -  return 0;
> +  return false;
>  }
>  
>  /*
> 
> === modified file 'sql/ha_ndbcluster_binlog.h'
> --- a/sql/ha_ndbcluster_binlog.h	2011-02-08 10:11:09 +0000
> +++ b/sql/ha_ndbcluster_binlog.h	2011-02-09 07:58:07 +0000
> @@ -249,13 +249,27 @@ int ndb_create_table_from_engine(THD *th
>                                   const char *table_name);
>  int ndbcluster_binlog_start();
>  
> -int ndbcluster_setup_binlog_table_shares(THD *thd);
> +
> +/*
> +  Setup function for the ndb binlog component. The function should be
> +  called on startup until it succeeds(to allow initial setup) and with
> +  regular intervals afterwards to reconnect after a lost cluster
> +  connection
> +*/
> +bool ndb_binlog_setup(THD *thd);
> +
> +/*
> +  Will return true when the ndb binlog component is properly setup
> +  and ready to receive events from the cluster. As long as function
> +  returns false, all tables in this MySQL Server are opened in read only
> +  mode to avoid writes before the binlog is ready to record them.
> + */
> +bool ndb_binlog_is_read_only(void);
> +
>  extern NDB_SHARE *ndb_apply_status_share;
>  extern NDB_SHARE *ndb_schema_share;
>  
>  extern my_bool ndb_binlog_running;
> -extern my_bool ndb_binlog_tables_inited;
> -extern my_bool ndb_binlog_is_ready;
>  
>  bool
>  ndbcluster_show_status_binlog(THD* thd, stat_print_fn *stat_print,
> 
> 
> 
> 
>