OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK > Class Template Reference

A size-based allocator that caches blocks for quicker access, but if the pool is exhausted it will use the heap. More...

#include <Dynamic_Cached_Allocator_With_Overflow_T.h>

List of all members.

Public Member Functions
	Dynamic_Cached_Allocator_With_Overflow (size_t n_chunks, size_t chunk_size)
	~Dynamic_Cached_Allocator_With_Overflow (void)
	Clear things up.
void *	malloc (size_t nbytes=0)
virtual void *	calloc (size_t, char= '\0')
virtual void *	calloc (size_t, size_t, char= '\0')
void	free (void *ptr)
	Return a chunk of memory back to free list cache.
size_t	pool_depth (void)
	Return the number of chunks available in the cache.
size_t	available ()
Public Attributes
u_long	allocs_from_heap_
	number of allocations from the heap.
u_long	allocs_from_pool_
	number of allocations from the pool.
u_long	frees_to_heap_
	number of frees returned to the heap
u_long	frees_to_pool_
	number of frees returned to the pool
Private Attributes
char *	pool_
char *	last_
	The end of the pool.
ACE_Locked_Free_List< ACE_Cached_Mem_Pool_Node< char >, ACE_LOCK >	free_list_
size_t	chunk_size_
	Remember the size of our chunks.

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Detailed Description

template<class ACE_LOCK>
class OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK >

A size-based allocator that caches blocks for quicker access, but if the pool is exhausted it will use the heap.

This class enables caching of dynamically allocated, fixed-size chunks. Notice that the chunk_size must be greater than or equal to sizeof (void*) for this to work properly.

This class can be configured flexibly with different types of ACE_LOCK strategies that support the ACE_Thread_Mutex and ACE_Process_Mutex constructor API.

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Constructor & Destructor Documentation

template<class ACE_LOCK>

OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK >::Dynamic_Cached_Allocator_With_Overflow	(	size_t	n_chunks,
		size_t	chunk_size
	)			[inline]

Create a cached memory pool with n_chunks chunks each with chunk_size size.

template<class ACE_LOCK>

OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK >::~Dynamic_Cached_Allocator_With_Overflow

(

void

)

[inline]

Clear things up.

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Member Function Documentation

template<class ACE_LOCK>

size_t OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK >::available

(

)

[inline]

How many chunks are available at this time.

template<class ACE_LOCK>

virtual void* OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK >::calloc	(	size_t	,
		size_t	,
		char	= '\0'
	)			[inline, virtual]

This method is a no-op and just returns 0 since the free list only works with fixed sized entities.

template<class ACE_LOCK>

virtual void* OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK >::calloc	(	size_t	,
		char	= '\0'
	)			[inline, virtual]

Get a chunk of memory from free list cache, giving them initial_value. Note that nbytes is only checked to make sure that it's less or equal to chunk_size, and is otherwise ignored since calloc() always returns a pointer to an item of chunk_size.

template<class ACE_LOCK>

void OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK >::free

(

void *

ptr

)

[inline]

Return a chunk of memory back to free list cache.

template<class ACE_LOCK>

void* OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK >::malloc

(

size_t

nbytes = 0

)

[inline]

Get a chunk of memory from free list cache. Note that nbytes is only checked to make sure that it's less or equal to chunk_size, and is otherwise ignored since malloc() always returns a pointer to an item of chunk_size size.

template<class ACE_LOCK>

size_t OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK >::pool_depth

(

void

)

[inline]

Return the number of chunks available in the cache.

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Member Data Documentation

template<class ACE_LOCK>

u_long OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK >::allocs_from_heap_

number of allocations from the heap.

template<class ACE_LOCK>

u_long OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK >::allocs_from_pool_

number of allocations from the pool.

template<class ACE_LOCK>

size_t OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK >::chunk_size_ [private]

Remember the size of our chunks.

template<class ACE_LOCK>

ACE_Locked_Free_List<ACE_Cached_Mem_Pool_Node<char>, ACE_LOCK> OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK >::free_list_ [private]

Maintain a cached memory free list. We use char as template parameter, although sizeof(char) is usually less than sizeof(void*). Really important is that chunk_size must be greater or equal to sizeof(void*).

template<class ACE_LOCK>

u_long OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK >::frees_to_heap_

number of frees returned to the heap

template<class ACE_LOCK>

u_long OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK >::frees_to_pool_

number of frees returned to the pool

template<class ACE_LOCK>

char* OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK >::last_ [private]

The end of the pool.

template<class ACE_LOCK>

char* OpenDDS::DCPS::Dynamic_Cached_Allocator_With_Overflow< ACE_LOCK >::pool_ [private]

Remember how we allocate the memory in the first place so we can clear things up later.

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

• Dynamic_Cached_Allocator_With_Overflow_T.h

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