a typed memory pool that saves time spent allocation small object. This is typically used by container such as DataVector and DataList More...

#include <DataPool.h>

Collaboration diagram for DataPool< VALUE, clear >:

Classes
class	const_iterator

class	iterator

Public Types
typedef handle_t::pointer	pointer

typedef size_t	size_type

Public Member Functions
	DataPool (size_type n=0)
	Constructors: More...

	DataPool (const EventContext &ctx, size_type n=0)

	DataPool (SG::Arena *arena, size_type n=0)

void	reset ()
	release all elements in the pool. More...

void	erase ()
	free all memory in the pool. More...

void	reserve (unsigned int size)
	Set the desired capacity. More...

void	prepareToAdd (unsigned int size)
	Prepare to add cached elements. More...

unsigned int	capacity ()
	return capacity of pool OK More...

unsigned int	allocated ()
	return size already allocated OK More...

iterator	begin ()
	begin iterators over pool More...

const_iterator	begin () const

iterator	end ()
	the end() method will allow looping over only valid elements and not over ALL elements of the pool More...

const_iterator	end () const

pointer	nextElementPtr ()
	obtain the next available element in pool by pointer pool is resized if its limit has been reached One must be sure to completely reset each object since it has values set in the previous event. More...

Static Public Member Functions
static const std::string &	typeName ()
	typename of pool More...

Private Types
typedef SG::ArenaPoolAllocator	alloc_t

typedef SG::ArenaCachingHandle< VALUE, alloc_t >	handle_t

Static Private Member Functions
static alloc_t::Params	initParams ()

static void	callClear (SG::ArenaAllocatorBase::pointer p)

Private Attributes
handle_t	m_handle

Static Private Attributes
static const alloc_t::Params	s_params

static constexpr size_t	s_minRefCount = 1024
	minimum number of elements in pool More...

Detailed Description

template<typename VALUE, DataPoolClearFuncPtr_t< VALUE > clear = nullptr>
class DataPool< VALUE, clear >

a typed memory pool that saves time spent allocation small object. This is typically used by container such as DataVector and DataList

A DataPool instance, acts as handle to the pool for the declared type. In the typical DataVector usage each store has a collection of pools distinguished by type. So for the same active store the same pool is used.

Declaring DataPool instances as static will cause thread-safety problems, and thus should no longer be done.

Also be aware that a creating a DataPool object acquires a lock on the underlying thread-specific allocator. If you're just using one at a time, there shouldn't be a problem. There is a potential for deadlock if you have a block of code that creates two DataPool objects, and another code block that creates DataPool objects for the same types but in the opposite order.

You can optionally provide (as a template argument) a function to be called on an object when it is returned to the pool. This can be used to reset the state, release memory, etc. This must be a static function, not a lambda, and since it's used as a template argument, it should not be in an anonymous namespace (should have public linkage). Also be aware that clear argument will have an effect only for the first DataPool object to be created for a given VALUE.

Author: Srini Rajagopalan, scott snyder

Definition at line 46 of file DataPool.h.

Member Typedef Documentation

◆ alloc_t

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

typedef SG::ArenaPoolAllocator DataPool< VALUE, clear >::alloc_t

private

Definition at line 49 of file DataPool.h.

◆ handle_t

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

typedef SG::ArenaCachingHandle<VALUE, alloc_t> DataPool< VALUE, clear >::handle_t

private

Definition at line 50 of file DataPool.h.

◆ pointer

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

typedef handle_t::pointer DataPool< VALUE, clear >::pointer

Definition at line 53 of file DataPool.h.

◆ size_type

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

typedef size_t DataPool< VALUE, clear >::size_type

Definition at line 54 of file DataPool.h.

Constructor & Destructor Documentation

◆ DataPool() [1/3]

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

DataPool< VALUE, clear >::DataPool ( size_type n = 0 )

Constructors:

◆ DataPool() [2/3]

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

DataPool< VALUE, clear >::DataPool	(	const EventContext &	ctx,
		size_type	n = `0`
	)

◆ DataPool() [3/3]

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

DataPool< VALUE, clear >::DataPool	(	SG::Arena *	arena,
		size_type	n = `0`
	)

Member Function Documentation

◆ allocated()

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

unsigned int DataPool< VALUE, clear >::allocated ( )

return size already allocated OK

◆ begin() [1/2]

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

iterator DataPool< VALUE, clear >::begin ( )

begin iterators over pool

◆ begin() [2/2]

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

const_iterator DataPool< VALUE, clear >::begin ( ) const

◆ callClear()

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

static void DataPool< VALUE, clear >::callClear ( SG::ArenaAllocatorBase::pointer p )

staticprivate

◆ capacity()

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

unsigned int DataPool< VALUE, clear >::capacity ( )

return capacity of pool OK

◆ end() [1/2]

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

iterator DataPool< VALUE, clear >::end ( )

the end() method will allow looping over only valid elements and not over ALL elements of the pool

◆ end() [2/2]

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

const_iterator DataPool< VALUE, clear >::end ( ) const

◆ erase()

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

void DataPool< VALUE, clear >::erase ( )

free all memory in the pool.

◆ initParams()

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

static alloc_t::Params DataPool< VALUE, clear >::initParams ( )

staticprivate

◆ nextElementPtr()

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

pointer DataPool< VALUE, clear >::nextElementPtr ( )

obtain the next available element in pool by pointer pool is resized if its limit has been reached One must be sure to completely reset each object since it has values set in the previous event.

◆ prepareToAdd()

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

void DataPool< VALUE, clear >::prepareToAdd ( unsigned int size )

Prepare to add cached elements.

Parameters

size	Additional elements to add

If (current capacity - allocated elements) is less than the requested elements additional space will be allocated by calling reserve (allocated + size). Otherwise nothing will be done

◆ reserve()

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

void DataPool< VALUE, clear >::reserve ( unsigned int size )

Set the desired capacity.

Parameters

size	The desired capacity

If size is greater than the total number of elements currently cached (allocated), then space for more will be allocated. This will be done in blocks. Therefore the allocator may allocate more elements than is requested.

If size is smaller than the total number of elements currently cached, as many blocks as possible will be released back to the system.

◆ reset()

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

void DataPool< VALUE, clear >::reset ( )

release all elements in the pool.

◆ typeName()

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

static const std::string& DataPool< VALUE, clear >::typeName ( )

static

typename of pool

Member Data Documentation

◆ m_handle

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

handle_t DataPool< VALUE, clear >::m_handle

private

Definition at line 182 of file DataPool.h.

◆ s_minRefCount

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

constexpr size_t DataPool< VALUE, clear >::s_minRefCount = 1024

staticconstexprprivate

minimum number of elements in pool

Definition at line 187 of file DataPool.h.

◆ s_params

template<typename VALUE , DataPoolClearFuncPtr_t< VALUE > clear = nullptr>

const alloc_t::Params DataPool< VALUE, clear >::s_params

staticprivate

Definition at line 184 of file DataPool.h.

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

DataPool.h

Classes

Public Types

Public Member Functions

Static Public Member Functions

Private Types

Static Private Member Functions

Private Attributes

Static Private Attributes

Detailed Description

template<typename VALUE, DataPoolClearFuncPtr_t< VALUE > clear = nullptr> class DataPool< VALUE, clear >

Member Typedef Documentation

◆ alloc_t

◆ handle_t

◆ pointer

◆ size_type

Constructor & Destructor Documentation

◆ DataPool() [1/3]

◆ DataPool() [2/3]

◆ DataPool() [3/3]

Member Function Documentation

◆ allocated()

◆ begin() [1/2]

◆ begin() [2/2]

◆ callClear()

◆ capacity()

◆ end() [1/2]

◆ end() [2/2]

◆ erase()

◆ initParams()

◆ nextElementPtr()

◆ prepareToAdd()

◆ reserve()

◆ reset()

◆ typeName()

Member Data Documentation

◆ m_handle

◆ s_minRefCount

◆ s_params

template<typename VALUE, DataPoolClearFuncPtr_t< VALUE > clear = nullptr>
class DataPool< VALUE, clear >