Commit 23776f53 authored by unknown's avatar unknown
Browse files

Fix for the following bugs: 

  - BUG#22306: STOP INSTANCE can not be applied for instances in Crashed,
    Failed and Abandoned;
  - BUG#23476: DROP INSTANCE does not work
  - BUG#23215: STOP INSTANCE takes too much time

BUG#22306:
The problem was that STOP INSTANCE checked that mysqld is up and running.
If it was not so, STOP INSTANCE reported an error. Now, STOP INSTANCE
reports an error if the instance has been started (mysqld can be down).

BUG#23476:
The problem was that DROP INSTANCE tried to stop inactive instance. The fix is
trivial.

BUG#23215:
The problem was that locks were not acquired properly, so the
instance-monitoring thread could not acquire the mutex, holded by the
query-processing thread.

The fix is to simplify locking scheme by moving instance-related information to
Instance-class out of Guardian-class. This allows to get rid of storing a
separate list of Instance-information in Guardian and keeping it synchronized
with the original list in Instance_map.


server-tools/instance-manager/commands.cc:
  1. Introduce Instance_cmd class -- base class for the commands
     that deal with the one instance;
  2. Remove Instance_map argument from command constructors;
  3. Ensure, that Instance Map and Instance are locked in the proper order;
  4. Polishing.
server-tools/instance-manager/commands.h:
  1. Introduce Instance_cmd class -- base class for the commands
     that deal with the one instance;
  2. Remove Instance_map argument from command constructors;
  3. Polishing.
server-tools/instance-manager/guardian.cc:
  1. Move "extended" instance information to the Instance-class.
     That allows to get rid of storing instance-related container and data in
     Guardian class, that significantly simplifies locking schema.
  2. Polishing.
server-tools/instance-manager/guardian.h:
  1. Move "extended" instance information to the Instance-class.
     That allows to get rid of storing instance-related container and data in
     Guardian class, that significantly simplifies locking schema.
  2. Polishing.
server-tools/instance-manager/instance.cc:
  1. Move "extended" instance information to the Instance-class.
  2. Introduce new state STOPPED to mark that guarded instance
     is stopped and should not be restarted by Guardian.
  3. Polishing.
server-tools/instance-manager/instance.h:
  1. Move "extended" instance information to the Instance-class.
  2. Introduce new state STOPPED to mark that guarded instance
     is stopped and should not be restarted by Guardian.
  3. Polishing.
server-tools/instance-manager/instance_map.cc:
  1. Move flush_instances() from Instance_map to Manager.
  2. Polishing.
server-tools/instance-manager/instance_map.h:
  1. Move flush_instances() from Instance_map to Manager.
  2. Polishing.
server-tools/instance-manager/instance_options.h:
  Polishing.
server-tools/instance-manager/manager.cc:
  1. Move flush_instances() from Instance_map to Manager.
  2. Polishing.
server-tools/instance-manager/manager.h:
  1. Move flush_instances() from Instance_map to Manager.
  2. Polishing.
server-tools/instance-manager/user_map.cc:
  Polishing.
parent 6949b042

server-tools/instance-manager/commands.cc

+171 −119
Original line number Diff line number Diff line
@@ -29,6 +29,7 @@ 
#include "guardian.h"

#include "instance_map.h"

#include "log.h"

#include "manager.h"

#include "messages.h"

#include "mysqld_error.h"

#include "mysql_manager_error.h"
@@ -36,8 +37,11 @@ 
#include "priv.h"

#include "protocol.h"



/**************************************************************************

 {{{ Static functions.

**************************************************************************/



/*

/**

  modify_defaults_to_im_error -- a map of error codes of

  mysys::modify_defaults_file() into Instance Manager error codes.

*/
@@ -46,38 +50,25 @@ static const int modify_defaults_to_im_error[]= { 0, ER_OUT_OF_RESOURCES, 
                                                  ER_ACCESS_OPTION_FILE };





/*

  Add a string to a buffer.

/**

  Parse version number from the version string.



  SYNOPSIS

    put_to_buff()

    buff              buffer to add the string

    str               string to add

    position          offset in the buff to add a string

    parse_version_number()

    version_str

    version

    version_size



  DESCRIPTION

    TODO



  Function to add a string to the buffer. It is different from

  store_to_protocol_packet, which is used in the protocol.cc.

  The last one also stores the length of the string in a special way.

  This is required for MySQL client/server protocol support only.

  TODO: Move this function to Instance_options and parse version number

  only once.



  RETURN

    0 - ok

    1 - error occured

  NOTE: This function is used only in SHOW INSTANCE STATUS statement at the

  moment.

*/



static inline int put_to_buff(Buffer *buff, const char *str, uint *position)

{

  uint len= strlen(str);

  if (buff->append(*position, str, len))

    return 1;



  *position+= len;

  return 0;

}





static int parse_version_number(const char *version_str, char *version,

                                uint version_size)

{
@@ -102,6 +93,9 @@ static int parse_version_number(const char *version_str, char *version, 
  return 0;

}



/**************************************************************************

  }}}

**************************************************************************/



/**************************************************************************

 Implementation of Instance_name.
@@ -122,7 +116,7 @@ Instance_name::Instance_name(const LEX_STRING *name) 
 Implementation of Show_instances.

**************************************************************************/



/*

/**

  Implementation of SHOW INSTANCES statement.



  Possible error codes:
@@ -172,7 +166,6 @@ int Show_instances::write_data(st_net *net) 
  Instance *instance;

  Instance_map::Iterator iterator(instance_map);



  instance_map->guardian->lock();

  instance_map->lock();



  while ((instance= iterator.next()))
@@ -180,20 +173,25 @@ int Show_instances::write_data(st_net *net) 
    Buffer send_buf;  /* buffer for packets */

    uint pos= 0;



    instance->lock();



    const char *instance_name= instance->options.instance_name.str;

    const char *state_name= instance_map->get_instance_state_name(instance);

    const char *state_name= instance->get_state_name();



    if (store_to_protocol_packet(&send_buf, instance_name, &pos) ||

        store_to_protocol_packet(&send_buf, state_name, &pos) ||

        my_net_write(net, send_buf.buffer, pos))

    {

      err_status= TRUE;

      break;

    }



    instance->unlock();



    if (err_status)

      break;

  }



  instance_map->unlock();

  instance_map->guardian->unlock();



  return err_status ? ER_OUT_OF_RESOURCES : 0;

}
@@ -203,7 +201,7 @@ int Show_instances::write_data(st_net *net) 
 Implementation of Flush_instances.

**************************************************************************/



/*

/**

  Implementation of FLUSH INSTANCES statement.



  Possible error codes:
@@ -213,36 +211,19 @@ int Show_instances::write_data(st_net *net) 


int Flush_instances::execute(st_net *net, ulong connection_id)

{

  instance_map->guardian->lock();

  instance_map->lock();



  if (instance_map->is_there_active_instance())

  {

    instance_map->unlock();

    instance_map->guardian->unlock();

    return ER_THERE_IS_ACTIVE_INSTACE;

  }



  if (instance_map->flush_instances())

  {

    instance_map->unlock();

    instance_map->guardian->unlock();

  if (Manager::flush_instances())

    return ER_OUT_OF_RESOURCES;

  }



  instance_map->unlock();

  instance_map->guardian->unlock();



  return net_send_ok(net, connection_id, NULL) ? ER_OUT_OF_RESOURCES : 0;

}





/**************************************************************************

 Implementation of Abstract_instance_cmd.

 Implementation of Instance_cmd.

**************************************************************************/



Abstract_instance_cmd::Abstract_instance_cmd(const LEX_STRING *instance_name_arg)

  :instance_name(instance_name_arg)

Instance_cmd::Instance_cmd(const LEX_STRING *instance_name_arg):

   instance_name(instance_name_arg)

{

  /*

    MT-NOTE: we can not make a search for Instance object here,
@@ -251,14 +232,25 @@ Abstract_instance_cmd::Abstract_instance_cmd(const LEX_STRING *instance_name_arg 
}





/**************************************************************************

 Implementation of Abstract_instance_cmd.

**************************************************************************/



Abstract_instance_cmd::Abstract_instance_cmd(

  const LEX_STRING *instance_name_arg)

  :Instance_cmd(instance_name_arg)

{

}





int Abstract_instance_cmd::execute(st_net *net, ulong connection_id)

{

  int err_code;

  Instance *instance;



  instance_map->lock();



  {

    Instance *instance= instance_map->find(get_instance_name());

  instance= instance_map->find(get_instance_name());



  if (!instance)

  {
@@ -266,10 +258,12 @@ int Abstract_instance_cmd::execute(st_net *net, ulong connection_id) 
    return ER_BAD_INSTANCE_NAME;

  }



  instance->lock();

  instance_map->unlock();



  err_code= execute_impl(net, instance);

  }



  instance_map->unlock();

  instance->unlock();



  if (!err_code)

    err_code= send_ok_response(net, connection_id);
@@ -288,7 +282,7 @@ Show_instance_status::Show_instance_status(const LEX_STRING *instance_name_arg) 
}





/*

/**

  Implementation of SHOW INSTANCE STATUS statement.



  Possible error codes:
@@ -363,19 +357,14 @@ int Show_instance_status::write_data(st_net *net, Instance *instance) 
  char version_num_buf[MAX_VERSION_LENGTH];

  uint pos= 0;



  const char *state_name;

  const char *state_name= instance->get_state_name();

  const char *version_tag= "unknown";

  const char *version_num= "unknown";

  const char *mysqld_compatible_status;



  instance_map->guardian->lock();

  state_name= instance_map->get_instance_state_name(instance);

  mysqld_compatible_status= instance->is_mysqld_compatible() ? "yes" : "no";

  instance_map->guardian->unlock();

  const char *mysqld_compatible_status=

    instance->is_mysqld_compatible() ? "yes" : "no";



  if (instance->options.mysqld_version)

  {



    if (parse_version_number(instance->options.mysqld_version, version_num_buf,

                             sizeof(version_num_buf)))

      return ER_OUT_OF_RESOURCES;
@@ -409,7 +398,7 @@ Show_instance_options::Show_instance_options( 
}





/*

/**

  Implementation of SHOW INSTANCE OPTIONS statement.



  Possible error codes:
@@ -505,23 +494,33 @@ Start_instance::Start_instance(const LEX_STRING *instance_name_arg) 
}





/*

/**

  Implementation of START INSTANCE statement.



  Possible error codes:

    ER_BAD_INSTANCE_NAME        The instance with the given name does not exist

    ER_OUT_OF_RESOURCES         Not enough resources to complete the operation

    ER_INSTANCE_MISCONFIGURED   The instance configuration is invalid

    ER_INSTANCE_ALREADY_STARTED The instance is already started

    ER_CANNOT_START_INSTANCE    The instance could not have been started



  TODO: as soon as this method operates only with Instance, we probably

  should introduce a new method (execute_stop_instance()) in Instance and

  just call it from here.

*/



int Start_instance::execute_impl(st_net * /* net */, Instance *instance)

{

  int err_code;

  if (!instance->is_configured())

    return ER_INSTANCE_MISCONFIGURED;



  if ((err_code= instance->start()))

    return err_code;

  if (instance->is_active())

    return ER_INSTANCE_ALREADY_STARTED;



  if (instance->start_mysqld())

    return ER_CANNOT_START_INSTANCE;



  if (!(instance->options.nonguarded))

    instance_map->guardian->guard(instance);

  instance->reset_stat();

  instance->set_state(Instance::NOT_STARTED);



  return 0;

}
@@ -546,25 +545,26 @@ Stop_instance::Stop_instance(const LEX_STRING *instance_name_arg) 
}





/*

/**

  Implementation of STOP INSTANCE statement.



  Possible error codes:

    ER_BAD_INSTANCE_NAME        The instance with the given name does not exist

    ER_OUT_OF_RESOURCES         Not enough resources to complete the operation



  TODO: as soon as this method operates only with Instance, we probably

  should introduce a new method (execute_stop_instance()) in Instance and

  just call it from here.

*/



int Stop_instance::execute_impl(st_net * /* net */, Instance *instance)

{

  int err_code;

  if (!instance->is_active())

    return ER_INSTANCE_IS_NOT_STARTED;



  if (!(instance->options.nonguarded))

    instance_map->guardian->stop_guard(instance);

  instance->set_state(Instance::STOPPED);



  if ((err_code= instance->stop()))

    return err_code;



  return 0;

  return instance->stop_mysqld() ? ER_STOP_INSTANCE : 0;

}
@@ -582,12 +582,12 @@ int Stop_instance::send_ok_response(st_net *net, ulong connection_id) 
**************************************************************************/



Create_instance::Create_instance(const LEX_STRING *instance_name_arg)

  :instance_name(instance_name_arg)

  :Instance_cmd(instance_name_arg)

{

}





/*

/**

  This operation initializes Create_instance object.



  SYNOPSIS
@@ -604,7 +604,7 @@ bool Create_instance::init(const char **text) 
}





/*

/**

  This operation parses CREATE INSTANCE options.



  SYNOPSIS
@@ -724,7 +724,7 @@ bool Create_instance::parse_args(const char **text) 
}





/*

/**

  Implementation of CREATE INSTANCE statement.



  Possible error codes:
@@ -736,6 +736,7 @@ bool Create_instance::parse_args(const char **text) 
int Create_instance::execute(st_net *net, ulong connection_id)

{

  int err_code;

  Instance *instance;



  /* Check that the name is valid and there is no instance with such name. */
@@ -761,17 +762,26 @@ int Create_instance::execute(st_net *net, ulong connection_id) 
    return err_code;

  }



  instance= instance_map->find(get_instance_name());

  DBUG_ASSERT(instance);



  if ((err_code= create_instance_in_file(get_instance_name(), &options)))

  {

    Instance *instance= instance_map->find(get_instance_name());



    if (instance)

    instance_map->remove_instance(instance); /* instance is deleted here. */



    instance_map->unlock();

    return err_code;

  }



  /*

    CREATE INSTANCE must not lead to start instance, even if it guarded.



    TODO: The problem however is that if Instance Manager restarts after

    creating instance, the instance will be restarted (see also BUG#19718).

  */



  instance->set_state(Instance::STOPPED);



  /* That's all. */



  instance_map->unlock();
@@ -790,12 +800,12 @@ int Create_instance::execute(st_net *net, ulong connection_id) 
**************************************************************************/



Drop_instance::Drop_instance(const LEX_STRING *instance_name_arg)

  :Abstract_instance_cmd(instance_name_arg)

  :Instance_cmd(instance_name_arg)

{

}





/*

/**

  Implementation of DROP INSTANCE statement.



  Possible error codes:
@@ -804,14 +814,38 @@ Drop_instance::Drop_instance(const LEX_STRING *instance_name_arg) 
    ER_OUT_OF_RESOURCES         Not enough resources to complete the operation

*/



int Drop_instance::execute_impl(st_net * /* net */, Instance *instance)

int Drop_instance::execute(st_net *net, ulong connection_id)

{

  int err_code;

  Instance *instance;



  /* Lock Guardian, then Instance_map. */



  instance_map->lock();



  /* Find an instance. */



  instance= instance_map->find(get_instance_name());



  if (!instance)

  {

    instance_map->unlock();

    return ER_BAD_INSTANCE_NAME;

  }



  instance->lock();



  /* Check that the instance is offline. */



  if (instance_map->guardian->is_active(instance))

  if (instance->is_active())

  {

    instance->unlock();

    instance_map->unlock();



    return ER_DROP_ACTIVE_INSTANCE;

  }



  /* Try to remove instance from the file. */



  err_code= modify_defaults_file(Options::Main::config_file, NULL, NULL,

                                 get_instance_name()->str, MY_REMOVE_SECTION);
@@ -824,27 +858,30 @@ int Drop_instance::execute_impl(st_net * /* net */, Instance *instance) 
              (const char *) get_instance_name()->str,

              (const char *) Options::Main::config_file,

              (int) err_code);

  }



  if (err_code)

    instance->unlock();

    instance_map->unlock();



    return modify_defaults_to_im_error[err_code];

  }



  /* Remove instance from the instance map hash and Guardian's list. */

  /* Unlock the instance before destroy. */



  if (!instance->options.nonguarded)

    instance_map->guardian->stop_guard(instance);

  instance->unlock();



  if ((err_code= instance->stop()))

    return err_code;

  /*

    Remove instance from the instance map

    (the instance will be also destroyed here).

  */



  instance_map->remove_instance(instance);



  return 0;

}

  /* Unlock the instance map. */



  instance_map->unlock();



  /* That's all: send ok. */



int Drop_instance::send_ok_response(st_net *net, ulong connection_id)

{

  if (net_send_ok(net, connection_id, "Instance dropped"))

    return ER_OUT_OF_RESOURCES;
@@ -867,7 +904,7 @@ Show_instance_log::Show_instance_log(const LEX_STRING *instance_name_arg, 
}





/*

/**

  Implementation of SHOW INSTANCE LOG statement.



  Possible error codes:
@@ -1012,7 +1049,7 @@ Show_instance_log_files::Show_instance_log_files 
}





/*

/**

  Implementation of SHOW INSTANCE LOG FILES statement.



  Possible error codes:
@@ -1133,7 +1170,7 @@ int Show_instance_log_files::write_data(st_net *net, Instance *instance) 
 Implementation of Abstract_option_cmd.

**************************************************************************/



/*

/**

  Instance_options_list -- a data class representing a list of options for

  some instance.

*/
@@ -1251,7 +1288,7 @@ bool Abstract_option_cmd::init(const char **text) 
}





/*

/**

  Correct the option file. The "skip" option is used to remove the found

  option.
@@ -1290,8 +1327,8 @@ int Abstract_option_cmd::correct_file(Instance *instance, Named_value *option, 
}





/*

  Implementation of SET statement.

/**

  Lock Instance Map and call execute_impl().



  Possible error codes:

    ER_BAD_INSTANCE_NAME        The instance with the given name does not exist
@@ -1341,6 +1378,11 @@ Abstract_option_cmd::get_instance_options_list(const LEX_STRING *instance_name) 
}





/**

  Skeleton implementation of option-management command.



  MT-NOTE: Instance Map is locked before calling this operation.

*/

int Abstract_option_cmd::execute_impl(st_net *net, ulong connection_id)

{

  int err_code= 0;
@@ -1352,12 +1394,18 @@ int Abstract_option_cmd::execute_impl(st_net *net, ulong connection_id) 
    Instance_options_list *lst=

      (Instance_options_list *) hash_element(&instance_options_map, i);



    bool instance_is_active;



    lst->instance= instance_map->find(lst->get_instance_name());



    if (!lst->instance)

      return ER_BAD_INSTANCE_NAME;



    if (instance_map->guardian->is_active(lst->instance))

    lst->instance->lock();

    instance_is_active= lst->instance->is_active();

    lst->instance->unlock();



    if (instance_is_active)

      return ER_INSTANCE_IS_ACTIVE;

  }
@@ -1368,6 +1416,8 @@ int Abstract_option_cmd::execute_impl(st_net *net, ulong connection_id) 
    Instance_options_list *lst=

      (Instance_options_list *) hash_element(&instance_options_map, i);



    lst->instance->lock();



    for (int j= 0; j < lst->options.get_size(); ++j)

    {

      Named_value option= lst->options.get_element(j);
@@ -1377,6 +1427,8 @@ int Abstract_option_cmd::execute_impl(st_net *net, ulong connection_id) 
        break;

    }



    lst->instance->unlock();



    if (err_code)

      break;

  }
@@ -1392,7 +1444,7 @@ int Abstract_option_cmd::execute_impl(st_net *net, ulong connection_id) 
 Implementation of Set_option.

**************************************************************************/



/*

/**

  This operation parses SET options.



  SYNOPSIS
@@ -1566,7 +1618,7 @@ int Set_option::process_option(Instance *instance, Named_value *option) 
 Implementation of Unset_option.

**************************************************************************/



/*

/**

  This operation parses UNSET options.



  SYNOPSIS
@@ -1662,7 +1714,7 @@ bool Unset_option::parse_args(const char **text) 
}





/*

/**

  Implementation of UNSET statement.



  Possible error codes:

server-tools/instance-manager/commands.h

+65 −39
Original line number Diff line number Diff line
@@ -30,7 +30,7 @@ 
#endif





/*

/**

  Print all instances of this instance manager.

  Grammar: SHOW INSTANCES

*/
@@ -50,7 +50,7 @@ class Show_instances: public Command 
};





/*

/**

  Reread configuration file and refresh internal cache.

  Grammar: FLUSH INSTANCES

*/
@@ -66,11 +66,50 @@ class Flush_instances: public Command 
};





/*

/**

  Base class for Instance-specific commands

  (commands that operate on one instance).



  Instance_cmd extends Command class by:

    - an attribute for storing instance name;

    - code to initialize instance name in constructor;

    - an accessor to get instance name.

*/



class Instance_cmd : public Command

{

public:

  Instance_cmd(const LEX_STRING *instance_name_arg);



protected:

  inline const LEX_STRING *get_instance_name() const

  {

    return instance_name.get_str();

  }



private:

  Instance_name instance_name;

};





/**

  Abstract class for Instance-specific commands.



  Abstract_instance_cmd extends Instance_cmd by providing a common

  framework for writing command-implementations. Basically, the class

  implements Command::execute() pure virtual function in the following

  way:

    - Lock Instance_map;

    - Get an instance by name. Return an error, if there is no such

      instance;

    - Lock the instance;

    - Unlock Instance_map;

    - Call execute_impl(), which should be implemented in derived class;

    - Unlock the instance;

    - Send response to the client and return error status.

*/



class Abstract_instance_cmd: public Command

class Abstract_instance_cmd: public Instance_cmd

{

public:

  Abstract_instance_cmd(const LEX_STRING *instance_name_arg);
@@ -79,29 +118,24 @@ class Abstract_instance_cmd: public Command 
  virtual int execute(st_net *net, ulong connection_id);



protected:

  /* MT-NOTE: this operation is called under acquired Instance_map's lock. */

  /**

    This operation is intended to contain command-specific implementation.



    MT-NOTE: this operation is called under acquired Instance's lock.

  */

  virtual int execute_impl(st_net *net, Instance *instance) = 0;



  /*

  /**

    This operation is invoked on successful return of execute_impl() and is

    intended to send closing data.



    MT-NOTE: this operation is called under released Instance_map's lock.

    MT-NOTE: this operation is called under released Instance's lock.

  */

  virtual int send_ok_response(st_net *net, ulong connection_id) = 0;



protected:

  inline const LEX_STRING *get_instance_name() const

  {

    return instance_name.get_str();

  }



private:

  Instance_name instance_name;

};





/*

/**

  Print status of an instance.

  Grammar: SHOW INSTANCE STATUS <instance_name>

*/
@@ -121,7 +155,7 @@ class Show_instance_status: public Abstract_instance_cmd 
};





/*

/**

  Print options of chosen instance.

  Grammar: SHOW INSTANCE OPTIONS <instance_name>

*/
@@ -141,7 +175,7 @@ class Show_instance_options: public Abstract_instance_cmd 
};





/*

/**

  Start an instance.

  Grammar: START INSTANCE <instance_name>

*/
@@ -157,7 +191,7 @@ class Start_instance: public Abstract_instance_cmd 
};





/*

/**

  Stop an instance.

  Grammar: STOP INSTANCE <instance_name>

*/
@@ -173,12 +207,12 @@ class Stop_instance: public Abstract_instance_cmd 
};





/*

/**

  Create an instance.

  Grammar: CREATE INSTANCE <instance_name> [<options>]

*/



class Create_instance: public Command

class Create_instance: public Instance_cmd

{

public:

  Create_instance(const LEX_STRING *instance_name_arg);
@@ -189,22 +223,15 @@ class Create_instance: public Command 
protected:

  virtual int execute(st_net *net, ulong connection_id);



  inline const LEX_STRING *get_instance_name() const

  {

    return instance_name.get_str();

  }



private:

  bool parse_args(const char **text);



private:

  Instance_name instance_name;



  Named_value_arr options;

};





/*

/**

  Drop an instance.

  Grammar: DROP INSTANCE <instance_name>
@@ -213,18 +240,17 @@ class Create_instance: public Command 
  is removed from the instance map.

*/



class Drop_instance: public Abstract_instance_cmd

class Drop_instance: public Instance_cmd

{

public:

  Drop_instance(const LEX_STRING *instance_name_arg);



protected:

  virtual int execute_impl(st_net *net, Instance *instance);

  virtual int send_ok_response(st_net *net, ulong connection_id);

  virtual int execute(st_net *net, ulong connection_id);

};





/*

/**

  Print requested part of the log.

  Grammar:

    SHOW <instance_name> LOG {ERROR | SLOW | GENERAL} size[, offset_from_end]
@@ -252,7 +278,7 @@ class Show_instance_log: public Abstract_instance_cmd 
};





/*

/**

  Shows the list of the log files, used by an instance.

  Grammar: SHOW <instance_name> LOG FILES

*/
@@ -272,7 +298,7 @@ class Show_instance_log_files: public Abstract_instance_cmd 
};





/*

/**

  Abstract class for option-management commands.

*/
@@ -312,7 +338,7 @@ class Abstract_option_cmd: public Command 
};





/*

/**

  Set an option for the instance.

  Grammar: SET instance_name.option[=option_value][, ...]

*/
@@ -329,7 +355,7 @@ class Set_option: public Abstract_option_cmd 
};





/*

/**

  Remove option of the instance.

  Grammar: UNSET instance_name.option[, ...]

*/
@@ -346,7 +372,7 @@ class Unset_option: public Abstract_option_cmd 
};





/*

/**

  Syntax error command.



  This command is issued if parser reported a syntax error. We need it to

server-tools/instance-manager/guardian.cc

+259 −284

File changed.

Preview size limit exceeded, changes collapsed.

server-tools/instance-manager/guardian.h

+51 −74
Original line number Diff line number Diff line
@@ -17,10 +17,12 @@ 
   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */





#include "thread_registry.h"

#include <my_global.h>

#include <my_sys.h>

#include <my_list.h>



#include "thread_registry.h"



#if defined(__GNUC__) && defined(USE_PRAGMA_INTERFACE)

#pragma interface

#endif
@@ -28,7 +30,6 @@ 
class Instance;

class Instance_map;

class Thread_registry;

struct GUARD_NODE;



/**

  The guardian thread is responsible for monitoring and restarting of guarded
@@ -38,97 +39,73 @@ struct GUARD_NODE; 
class Guardian: public Thread

{

public:

  /* states of an instance */

  enum enum_instance_state { NOT_STARTED= 1, STARTING, STARTED, JUST_CRASHED,

                             CRASHED, CRASHED_AND_ABANDONED, STOPPING };

  Guardian(Thread_registry *thread_registry_arg,

           Instance_map *instance_map_arg);

  ~Guardian();



  /*

    The Guardian list node structure. Guardian utilizes it to store

    guarded instances plus some additional info.

  */

  void init();



  struct GUARD_NODE

  {

    Instance *instance;

    /* state of an instance (i.e. STARTED, CRASHED, etc.) */

    enum_instance_state state;

    /* the amount of attemts to restart instance (cleaned up at success) */

    int restart_counter;

    /* triggered at a crash */

    time_t crash_moment;

    /* General time field. Used to provide timeouts (at shutdown and restart) */

    time_t last_checked;

  };

public:

  void request_shutdown();



  /* Return client state name. */

  static const char *get_instance_state_name(enum_instance_state state);

  bool is_stopped();



  Guardian(Thread_registry *thread_registry_arg,

           Instance_map *instance_map_arg,

           uint monitoring_interval_arg);

  virtual ~Guardian();

  /* Initialize or refresh the list of guarded instances */

  int init();

  /* Request guardian shutdown. Stop instances if needed */

  void request_shutdown();

  /* Start instance protection */

  int guard(Instance *instance, bool nolock= FALSE);

  /* Stop instance protection */

  int stop_guard(Instance *instance);

  /* Returns TRUE if guardian thread is stopped */

  int is_stopped();

  void lock();

  void unlock();



  /*

    Return an internal list node for the given instance if the instance is

    managed by Guardian. Otherwise, return NULL.

  void ping();



    MT-NOTE: must be called under acquired lock.

  */

  LIST *find_instance_node(Instance *instance);

protected:

  virtual void run();



  /* The operation is used to check if the instance is active or not. */

  bool is_active(Instance *instance);

private:

  void stop_instances();



  void process_instance(Instance *instance);



private:

  /*

    Return state of the given instance list node. The pointer must specify

    a valid list node.

    LOCK_guardian protectes the members in this section:

      - shutdown_requested;

      - stopped;



    Also, it is used for COND_guardian.

  */

  inline enum_instance_state get_instance_state(LIST *instance_node);

protected:

  /* Main funtion of the thread */

  virtual void run();

  pthread_mutex_t LOCK_guardian;



public:

  /*

    Guardian's main loop waits on this condition. So, it should be signalled

    each time, when instance state has been changed and we want Guardian to

    wake up.



    TODO: Change this to having data-scoped conditions, i.e. conditions,

    which indicate that some data has been changed.

  */

  pthread_cond_t COND_guardian;



private:

  /* Prepares Guardian shutdown. Stops instances is needed */

  int stop_instances();

  /* check instance state and act accordingly */

  void process_instance(Instance *instance, GUARD_NODE *current_node,

                        LIST **guarded_instances, LIST *elem);

  /*

    This variable is set to TRUE, when Manager thread is shutting down.

    The flag is used by Guardian thread to understand that it's time to

    finish.

  */

  bool shutdown_requested;



  int stopped;

  /*

    This flag is set to TRUE on shutdown by Guardian thread, when all guarded

    mysqlds are stopped.



    The flag is used in the Manager thread to wait for Guardian to stop all

    mysqlds.

  */

  bool stopped;



private:

  pthread_mutex_t LOCK_guardian;

  Thread_info thread_info;

  int monitoring_interval;

  Thread_registry *thread_registry;

  Instance_map *instance_map;

  LIST *guarded_instances;

  MEM_ROOT alloc;

  /* this variable is set to TRUE when we want to stop Guardian thread */

  bool shutdown_requested;

};





inline Guardian::enum_instance_state

Guardian::get_instance_state(LIST *instance_node)

{

  return ((GUARD_NODE *) instance_node->data)->state;

}

private:

  Guardian(const Guardian &);

  Guardian&operator =(const Guardian &);

};



#endif /* INCLUDES_MYSQL_INSTANCE_MANAGER_GUARDIAN_H */

server-tools/instance-manager/instance.cc

+417 −213

File changed.

Preview size limit exceeded, changes collapsed.