Main Page Namespace List Class Hierarchy Alphabetical List Compound List File List Namespace Members Compound Members File Members Related Pages

# TAO_Transport_Cache_Manager Class Reference

The Transport Cache Manager for TAO. More...

`#include <Transport_Cache_Manager.h>`

Collaboration diagram for TAO_Transport_Cache_Manager:

[legend]
List of all members.

## Public Types
typedef ACE_Hash_Map_Manager_Ex< TAO_Cache_ExtId, TAO_Cache_IntId, ACE_Hash< TAO_Cache_ExtId >, ACE_Equal_To< TAO_Cache_ExtId >, ACE_Null_Mutex > | HASH_MAP
typedef HASH_MAP::iterator | HASH_MAP_ITER
typedef ACE_Hash_Map_Entry< TAO_Cache_ExtId, TAO_Cache_IntId > | HASH_MAP_ENTRY
typedef TAO_Condition< TAO_SYNCH_MUTEX > | CONDITION
## Public Methods
| TAO_Transport_Cache_Manager (TAO_ORB_Core &orb_core)
| Constructor.
virtual | ~TAO_Transport_Cache_Manager (void)
| Destructor.
int | cache_transport (TAO_Transport_Descriptor_Interface *prop, TAO_Transport *transport)
| Add the transport to the cache.
int | cache_idle_transport (TAO_Transport_Descriptor_Interface *prop, TAO_Transport *transport)
int | find_transport (TAO_Transport_Descriptor_Interface *prop, TAO_Transport *&transport)
int | purge (void)
| Remove entries from the cache depending upon the strategy.
int | purge_entry (HASH_MAP_ENTRY *&)
| Purge the entry from the Cache Map.
void | mark_invalid (HASH_MAP_ENTRY *&)
| Mark the entry as invalid for use but keep it in cache.
int | make_idle (HASH_MAP_ENTRY *&entry)
| Make the entry idle and ready for use.
int | update_entry (HASH_MAP_ENTRY *&entry)
int | close (TAO_Connection_Handler_Set &handlers)
size_t | current_size (void) const
| Return the current size of the cache.
size_t | total_size (void) const
| Return the total size of the cache.
HASH_MAP & | map (void)
| Return the underlying cache map.
## Private Types
typedef HASH_MAP_ENTRY ** | DESCRIPTOR_SET
## Private Methods
int | bind (TAO_Cache_ExtId &ext_id, TAO_Cache_IntId &int_id)
int | find (const TAO_Cache_ExtId &key, TAO_Cache_IntId &value)
int | bind_i (TAO_Cache_ExtId &ext_id, TAO_Cache_IntId &int_id)
int | find_i (const TAO_Cache_ExtId &key, TAO_Cache_IntId &value)
int | make_idle_i (HASH_MAP_ENTRY *&entry)
| Non-locking version and actual implementation of make_idle ().
int | close_i (TAO_Connection_Handler_Set &handlers)
| Non-locking version and actual implementation of close ().
int | purge_entry_i (HASH_MAP_ENTRY *&entry)
| Purge the entry from the Cache Map.
void | mark_invalid_i (HASH_MAP_ENTRY *&)
| Mark the entry as invalid for use but keep it in cache.
int | get_last_index_bind (TAO_Cache_ExtId &key, TAO_Cache_IntId &val, HASH_MAP_ENTRY *&entry)
int | is_entry_idle (HASH_MAP_ENTRY *&entry)
void | sort_set (DESCRIPTOR_SET &entries, int size)
| Sort the list of entries.
int | fill_set_i (DESCRIPTOR_SET &sorted_set)
int | wait_for_connection (TAO_Cache_ExtId &extid)
int | is_wakeup_useful (TAO_Cache_ExtId &extid)
| Is the wakeup useful todo some work?
## Static Private Methods
int | cpscmp (const void *a, const void *b)
| Used by qsort.
## Private Attributes
int | percent_
| The percentage of the cache to purge at one time.
TAO_Connection_Purging_Strategy * | purging_strategy_
| The underlying connection purging strategy.
HASH_MAP | cache_map_
| The hash map that has the connections.
CONDITION * | condition_
| The condition variable.
ACE_Lock * | cache_lock_
| The lock that is used by the cache map.
CORBA::ULong | muxed_number_
| Number of allowed muxed connections.
int | no_waiting_threads_
| Number of threads waiting for connections.
TAO_Cache_ExtId * | last_entry_returned_

## Detailed Description

The Transport Cache Manager for TAO.

This class provides interfaces associating a TAO_Cache_ExtId & TAO_Cache_IntId. This class is wrapper around the ACE_Hash_Map_Manager class which is used as a container to Cache the connections. This class protects the entries with a lock. The map is updated only by holding the lock. The more compelling reason to have the lock in this class and not in the Hash_Map is that, we do quite a bit of work in this class for which we need a lock.

## Member Typedef Documentation

typedef TAO_Condition<TAO_SYNCH_MUTEX> TAO_Transport_Cache_Manager::CONDITION

typedef HASH_MAP_ENTRY** TAO_Transport_Cache_Manager::DESCRIPTOR_SET`[private]`

typedef ACE_Hash_Map_Manager_Ex<TAO_Cache_ExtId, TAO_Cache_IntId, ACE_Hash<TAO_Cache_ExtId>, ACE_Equal_To<TAO_Cache_ExtId>, ACE_Null_Mutex> TAO_Transport_Cache_Manager::HASH_MAP

typedef ACE_Hash_Map_Entry<TAO_Cache_ExtId, TAO_Cache_IntId> TAO_Transport_Cache_Manager::HASH_MAP_ENTRY

typedef HASH_MAP::iterator TAO_Transport_Cache_Manager::HASH_MAP_ITER

## Constructor & Destructor Documentation

TAO_Transport_Cache_Manager::TAO_Transport_Cache_Manager | ( | TAO_ORB_Core & | orb_core | ) |

| Constructor.

TAO_Transport_Cache_Manager::~TAO_Transport_Cache_Manager | ( | void |  | ) | `[virtual]`

| Destructor. If the cache is not going to be locked then dont create a condition variable. Make the <muxed_number_> to 0, else a single thread could get into waiting mode

## Member Function Documentation

ACE_INLINE int TAO_Transport_Cache_Manager::bind | ( | TAO_Cache_ExtId & | ext_id,
|  | TAO_Cache_IntId & | int_id
| ) | `[private]`

| Associate <ext_id> with <int_id>. Grabs the lock and calls the implementation function bind_i.

int TAO_Transport_Cache_Manager::bind_i | ( | TAO_Cache_ExtId & | ext_id,
|  | TAO_Cache_IntId & | int_id
| ) | `[private]`

| Non-Locking version and actual implementation of bind () call. Calls bind on the Hash_Map_Manager that it holds. If the bind succeeds, it adds the Hash_Map_Entry in to the Transport for its reference. If the bind fails because of an exiting entry, this method calls the get_last_index_bind ().

ACE_INLINE int TAO_Transport_Cache_Manager::cache_idle_transport | ( | TAO_Transport_Descriptor_Interface * | prop,
|  | TAO_Transport * | transport
| ) |

| Similar to the one above, but the transport is left in `ACE_RECYCLABLE_IDLE_AND_PURGABLE` state.

ACE_INLINE int TAO_Transport_Cache_Manager::cache_transport | ( | TAO_Transport_Descriptor_Interface * | prop,
|  | TAO_Transport * | transport
| ) |

| Add the transport to the cache. The transport has the property definition based on which caching can be done. This method marks the transport `ACE_RECYCLABLE_BUSY` which helps the threads opening up connections to use the transport immediately.

ACE_INLINE int TAO_Transport_Cache_Manager::close | ( | TAO_Connection_Handler_Set & | handlers | ) |

| Close the underlying hash map manager and return any handlers still registered

int TAO_Transport_Cache_Manager::close_i | ( | TAO_Connection_Handler_Set & | handlers | ) | `[private]`

| Non-locking version and actual implementation of close ().

int TAO_Transport_Cache_Manager::cpscmp | ( | const void * | a,
|  | const void * | b
| ) | `[static, private]`

| Used by qsort.

ACE_INLINE size_t TAO_Transport_Cache_Manager::current_size | ( | void |  | ) | const

| Return the current size of the cache.

int TAO_Transport_Cache_Manager::fill_set_i | ( | DESCRIPTOR_SET & | sorted_set | ) | `[private]`

| Fill sorted_set in with the TAO_Transport_Descriptor_Interface's in a sorted order.

int TAO_Transport_Cache_Manager::find | ( | const TAO_Cache_ExtId & | key,
|  | TAO_Cache_IntId & | value
| ) | `[private]`

| Lookup entry<key,value> in the cache. Grabs the lock and calls the implementation function find_i.

int TAO_Transport_Cache_Manager::find_i | ( | const TAO_Cache_ExtId & | key,
|  | TAO_Cache_IntId & | value
| ) | `[private]`

| Non-locking version and actual implementation of find () call. This calls the find () on the underlying Hash_Map_Manager. If the find succeeds, it calls the get_idle_transport ().

int TAO_Transport_Cache_Manager::find_transport | ( | TAO_Transport_Descriptor_Interface * | prop,
|  | TAO_Transport *& | transport
| ) |

| Check the Transport Cache to check whether the connection exists in the Cache and return the connection

int TAO_Transport_Cache_Manager::get_last_index_bind | ( | TAO_Cache_ExtId & | key,
|  | TAO_Cache_IntId & | val,
|  | HASH_MAP_ENTRY *& | entry
| ) | `[private]`

| This is called by the bind () call when a bind fails with a available entry. When a new connection is created in TAO with an already existing endpoint, in addition to an exisitng one, we mark the connections with an index. This method, finds out the last highest index and binds the entry with an index = (last highest index + 1).

int TAO_Transport_Cache_Manager::is_entry_idle | ( | HASH_MAP_ENTRY *& | entry | ) | `[private]`

| Tries to find if the <int_id_> in entry is idle for use. If it is idle it is immediately markes as busy and returns a value of 1, else it returns a value of 0

int TAO_Transport_Cache_Manager::is_wakeup_useful | ( | TAO_Cache_ExtId & | extid | ) | `[private]`

| Is the wakeup useful todo some work?

ACE_INLINE int TAO_Transport_Cache_Manager::make_idle | ( | HASH_MAP_ENTRY *& | entry | ) |

| Make the entry idle and ready for use.

int TAO_Transport_Cache_Manager::make_idle_i | ( | HASH_MAP_ENTRY *& | entry | ) | `[private]`

| Non-locking version and actual implementation of make_idle ().

ACE_INLINE TAO_Transport_Cache_Manager::HASH_MAP & TAO_Transport_Cache_Manager::map | ( | void |  | ) |

| Return the underlying cache map.

ACE_INLINE void TAO_Transport_Cache_Manager::mark_invalid | ( | HASH_MAP_ENTRY *& |  | ) |

| Mark the entry as invalid for use but keep it in cache.

void TAO_Transport_Cache_Manager::mark_invalid_i | ( | HASH_MAP_ENTRY *& |  | ) | `[private]`

| Mark the entry as invalid for use but keep it in cache.

int TAO_Transport_Cache_Manager::purge | ( | void |  | ) |

| Remove entries from the cache depending upon the strategy.

ACE_INLINE int TAO_Transport_Cache_Manager::purge_entry | ( | HASH_MAP_ENTRY *& |  | ) |

| Purge the entry from the Cache Map.

int TAO_Transport_Cache_Manager::purge_entry_i | ( | HASH_MAP_ENTRY *& | entry | ) | `[private]`

| Purge the entry from the Cache Map.

void TAO_Transport_Cache_Manager::sort_set | ( | DESCRIPTOR_SET & | entries,
|  | int | size
| ) | `[private]`

| Sort the list of entries.

ACE_INLINE size_t TAO_Transport_Cache_Manager::total_size | ( | void |  | ) | const

| Return the total size of the cache.

int TAO_Transport_Cache_Manager::update_entry | ( | HASH_MAP_ENTRY *& | entry | ) |

| Mark the entry as touched. This call updates the purging strategy policy information.

int TAO_Transport_Cache_Manager::wait_for_connection | ( | TAO_Cache_ExtId & | extid | ) | `[private]`

| Wait for connections if we have reached the limit on the number of muxed connections. If not (ie. if we dont use a muxed connection or if we have not reached the limit) this just behaves as a no-op. <extid> has all the information about the connection that is being searched.

## Member Data Documentation

ACE_Lock* TAO_Transport_Cache_Manager::cache_lock_`[private]`

| The lock that is used by the cache map.

HASH_MAP TAO_Transport_Cache_Manager::cache_map_`[private]`

| The hash map that has the connections.

CONDITION* TAO_Transport_Cache_Manager::condition_`[private]`

| The condition variable.

TAO_Cache_ExtId* TAO_Transport_Cache_Manager::last_entry_returned_`[private]`

| This is for optimization purposes. In a situation where number of threads are waiting for connections, the last connection that is put back is cached here. This should prevent all th threads trying to search for their required entry.

CORBA::ULong TAO_Transport_Cache_Manager::muxed_number_`[private]`

| Number of allowed muxed connections.

int TAO_Transport_Cache_Manager::no_waiting_threads_`[private]`

| Number of threads waiting for connections.

int TAO_Transport_Cache_Manager::percent_`[private]`

| The percentage of the cache to purge at one time.

TAO_Connection_Purging_Strategy* TAO_Transport_Cache_Manager::purging_strategy_`[private]`

| The underlying connection purging strategy.

The documentation for this class was generated from the following files:

- Transport_Cache_Manager.h
- Transport_Cache_Manager.cpp
- Transport_Cache_Manager.inl