A connection strategy which caches connections to peers (represented by SVC_HANDLER instances), thereby allowing subsequent re-use of unused, but available, connections. This strategy should be used when the cache is bounded by maximum size. More...
#include <Cached_Connect_Strategy_T.h>
Public Member Functions | |
| ACE_Bounded_Cached_Connect_Strategy (size_t max_size, CACHING_STRATEGY &caching_s, ACE_Creation_Strategy< SVC_HANDLER > *cre_s=0, ACE_Concurrency_Strategy< SVC_HANDLER > *con_s=0, ACE_Recycling_Strategy< SVC_HANDLER > *rec_s=0, MUTEX *lock=0, int delete_lock=0) | |
| Constructor. | |
| virtual | ~ACE_Bounded_Cached_Connect_Strategy (void) |
| Destructor. | |
Public Attributes | |
| ACE_ALLOC_HOOK_DECLARE | |
| Declare the dynamic allocation hooks. | |
Protected Member Functions | |
| virtual int | find_or_create_svc_handler_i (SVC_HANDLER *&sh, const ACE_PEER_CONNECTOR_ADDR &remote_addr, ACE_Time_Value *timeout, const ACE_PEER_CONNECTOR_ADDR &local_addr, bool reuse_addr, int flags, int perms, ACE_Hash_Map_Entry< ACE_Refcounted_Hash_Recyclable< ACE_PEER_CONNECTOR_ADDR >, ACE_Pair< SVC_HANDLER *, ATTRIBUTES > > *&entry, int &found) |
Protected Attributes | |
| size_t | max_size_ |
| Max items in the cache, used as a bound for the creation of svc_handlers. | |
Private Types | |
| typedef ACE_Cached_Connect_Strategy_Ex < SVC_HANDLER, ACE_PEER_CONNECTOR_2, CACHING_STRATEGY, ATTRIBUTES, MUTEX > | CCSEBASE |
| typedef ACE_Refcounted_Hash_Recyclable < ACE_PEER_CONNECTOR_ADDR > | REFCOUNTED_HASH_RECYCLABLE_ADDRESS |
A connection strategy which caches connections to peers (represented by SVC_HANDLER instances), thereby allowing subsequent re-use of unused, but available, connections. This strategy should be used when the cache is bounded by maximum size.
Bounded_Cached_Connect_Strategy is intended to be used as a plug-in connection strategy for ACE_Strategy_Connector. It's added value is re-use of established connections and tweaking the role of the cache as per the caching strategy. Thanks to Edan Ayal <edana@bandwiz.com> for contributing this class and Susan Liebeskind <shl@janis.gtri.gatech.edu> for brainstorming about it.
Definition at line 205 of file Cached_Connect_Strategy_T.h.
typedef ACE_Cached_Connect_Strategy_Ex<SVC_HANDLER, ACE_PEER_CONNECTOR_2, CACHING_STRATEGY, ATTRIBUTES, MUTEX> ACE_Bounded_Cached_Connect_Strategy< SVC_HANDLER, ACE_PEER_CONNECTOR_1, CACHING_STRATEGY, ATTRIBUTES, MUTEX >::CCSEBASE [private] |
Definition at line 210 of file Cached_Connect_Strategy_T.h.
typedef ACE_Refcounted_Hash_Recyclable<ACE_PEER_CONNECTOR_ADDR> ACE_Bounded_Cached_Connect_Strategy< SVC_HANDLER, ACE_PEER_CONNECTOR_1, CACHING_STRATEGY, ATTRIBUTES, MUTEX >::REFCOUNTED_HASH_RECYCLABLE_ADDRESS [private] |
Reimplemented from ACE_Cached_Connect_Strategy_Ex< SVC_HANDLER, ACE_PEER_CONNECTOR_2, CACHING_STRATEGY, ATTRIBUTES, MUTEX >.
Definition at line 214 of file Cached_Connect_Strategy_T.h.
| ACE_Bounded_Cached_Connect_Strategy< SVC_HANDLER, ACE_PEER_CONNECTOR_1, CACHING_STRATEGY, ATTRIBUTES, MUTEX >::ACE_Bounded_Cached_Connect_Strategy | ( | size_t | max_size, | |
| CACHING_STRATEGY & | caching_s, | |||
| ACE_Creation_Strategy< SVC_HANDLER > * | cre_s = 0, |
|||
| ACE_Concurrency_Strategy< SVC_HANDLER > * | con_s = 0, |
|||
| ACE_Recycling_Strategy< SVC_HANDLER > * | rec_s = 0, |
|||
| MUTEX * | lock = 0, |
|||
| int | delete_lock = 0 | |||
| ) |
Constructor.
Definition at line 566 of file Cached_Connect_Strategy_T.cpp.
| ACE_Bounded_Cached_Connect_Strategy< SVC_HANDLER, ACE_PEER_CONNECTOR_1, CACHING_STRATEGY, ATTRIBUTES, MUTEX >::~ACE_Bounded_Cached_Connect_Strategy | ( | void | ) | [virtual] |
| int ACE_Bounded_Cached_Connect_Strategy< SVC_HANDLER, ACE_PEER_CONNECTOR_1, CACHING_STRATEGY, ATTRIBUTES, MUTEX >::find_or_create_svc_handler_i | ( | SVC_HANDLER *& | sh, | |
| const ACE_PEER_CONNECTOR_ADDR & | remote_addr, | |||
| ACE_Time_Value * | timeout, | |||
| const ACE_PEER_CONNECTOR_ADDR & | local_addr, | |||
| bool | reuse_addr, | |||
| int | flags, | |||
| int | perms, | |||
| ACE_Hash_Map_Entry< ACE_Refcounted_Hash_Recyclable< ACE_PEER_CONNECTOR_ADDR >, ACE_Pair< SVC_HANDLER *, ATTRIBUTES > > *& | entry, | |||
| int & | found | |||
| ) | [protected, virtual] |
Reimplemented from ACE_Cached_Connect_Strategy_Ex< SVC_HANDLER, ACE_PEER_CONNECTOR_2, CACHING_STRATEGY, ATTRIBUTES, MUTEX >.
Definition at line 586 of file Cached_Connect_Strategy_T.cpp.
{
REFCOUNTED_HASH_RECYCLABLE_ADDRESS search_addr (remote_addr);
// Try to find the address in the cache. Only if we don't find it
// do we create a new <SVC_HANDLER> and connect it with the server.
while (this->find (search_addr, entry) != -1)
{
// We found a cached svc_handler.
// Get the cached <svc_handler>
sh = entry->int_id_.first ();
// Is the connection clean?
int state_result= ACE::handle_ready (sh->peer ().get_handle (),
&ACE_Time_Value::zero,
1, // read ready
0, // write ready
1);// exception ready
if (state_result == 1)
{
// The connection was disconnected during idle.
// close the svc_handler down.
if (sh->close () == -1)
{
ACE_ASSERT (0);
return -1;
}
sh = 0;
// and rotate once more...
}
else if ((state_result == -1) && (errno == ETIME))
{
// Found!!!
// Set the flag
found = 1;
// Tell the <svc_handler> that it should prepare itself for
// being recycled.
if (this->prepare_for_recycling (sh) == -1)
{
ACE_ASSERT (0);
return -1;
}
return 0;
}
else // some other return value or error...
{
ACE_ASSERT (0); // just to see it coming
ACE_ERROR ((LM_ERROR,
ACE_TEXT ("(%t)ACE_Bounded_Cached_Connect_Strategy<>::")
ACE_TEXT ("find_or_create_svc_handler_i - ")
ACE_TEXT ("error polling server socket state.\n")));
return -1;
}
}
// Not found...
// Set the flag
found = 0;
// Check the limit of handlers...
if ((this->max_size_ > 0) &&
(this->connection_cache_.current_size () >= this->max_size_))
{
// Try to purge idle connections
if (this->purge_connections () == -1)
return -1;
// Check limit again.
if (this->connection_cache_.current_size () >= this->max_size_)
// still too much!
return -1;
// OK, we have room now...
}
// We need to use a temporary variable here since we are not
// allowed to change <sh> because other threads may use this
// when we let go of the lock during the OS level connect.
//
// Note that making a new svc_handler, connecting remotely,
// binding to the map, and assigning of the hint and recycler
// should be atomic to the outside world.
SVC_HANDLER *potential_handler = 0;
// Create a new svc_handler
if (this->make_svc_handler (potential_handler) == -1)
return -1;
// Connect using the svc_handler.
if (this->cached_connect (potential_handler,
remote_addr,
timeout,
local_addr,
reuse_addr,
flags,
perms) == -1)
{
// Close the svc handler.
potential_handler->close (0);
return -1;
}
else
{
// Insert the new SVC_HANDLER instance into the cache.
if (this->connection_cache_.bind (search_addr,
potential_handler,
entry) == -1)
{
// Close the svc handler and reset <sh>.
potential_handler->close (0);
return -1;
}
// Everything succeeded as planned. Assign <sh> to
// <potential_handler>.
sh = potential_handler;
// Set the recycler and the recycling act
this->assign_recycler (sh, this, entry);
}
return 0;
}
| ACE_Bounded_Cached_Connect_Strategy< SVC_HANDLER, ACE_PEER_CONNECTOR_1, CACHING_STRATEGY, ATTRIBUTES, MUTEX >::ACE_ALLOC_HOOK_DECLARE |
Declare the dynamic allocation hooks.
Reimplemented from ACE_Connect_Strategy< SVC_HANDLER, ACE_PEER_CONNECTOR_2 >.
Definition at line 231 of file Cached_Connect_Strategy_T.h.
size_t ACE_Bounded_Cached_Connect_Strategy< SVC_HANDLER, ACE_PEER_CONNECTOR_1, CACHING_STRATEGY, ATTRIBUTES, MUTEX >::max_size_ [protected] |
Max items in the cache, used as a bound for the creation of svc_handlers.
Definition at line 249 of file Cached_Connect_Strategy_T.h.
1.7.0