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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:

Collaboration graph
[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_MAPmap (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_Strategypurging_strategy_
 The underlying connection purging strategy.

HASH_MAP cache_map_
 The hash map that has the connections.

CONDITIONcondition_
 The condition variable.

ACE_Lockcache_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_ExtIdlast_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:
Generated on Fri Apr 2 17:37:25 2004 for TAO by doxygen1.2.18