rmm::mr::aligned_resource_adaptor< Upstream > Class Template Reference

Resource that adapts Upstream memory resource to allocate memory in a specified alignment size. More...

#include <aligned_resource_adaptor.hpp>

Inheritance diagram for rmm::mr::aligned_resource_adaptor< Upstream >:

Collaboration diagram for rmm::mr::aligned_resource_adaptor< Upstream >:

Public Member Functions
	aligned_resource_adaptor (device_async_resource_ref upstream, std::size_t alignment=rmm::CUDA_ALLOCATION_ALIGNMENT, std::size_t alignment_threshold=default_alignment_threshold)
	Construct an aligned resource adaptor using upstream to satisfy allocation requests. More...
	aligned_resource_adaptor (Upstream *upstream, std::size_t alignment=rmm::CUDA_ALLOCATION_ALIGNMENT, std::size_t alignment_threshold=default_alignment_threshold)
	Construct an aligned resource adaptor using upstream to satisfy allocation requests. More...
	aligned_resource_adaptor (aligned_resource_adaptor const &)=delete
	aligned_resource_adaptor (aligned_resource_adaptor &&)=delete
aligned_resource_adaptor &	operator= (aligned_resource_adaptor const &)=delete
aligned_resource_adaptor &	operator= (aligned_resource_adaptor &&)=delete
rmm::device_async_resource_ref	get_upstream_resource () const noexcept
	rmm::device_async_resource_ref to the upstream resource More...
Public Member Functions inherited from rmm::mr::device_memory_resource
	device_memory_resource (device_memory_resource const &)=default
	Default copy constructor.
	device_memory_resource (device_memory_resource &&) noexcept=default
	Default move constructor.
device_memory_resource &	operator= (device_memory_resource const &)=default
	Default copy assignment operator. More...
device_memory_resource &	operator= (device_memory_resource &&) noexcept=default
	Default move assignment operator. More...
void *	allocate (std::size_t bytes, cuda_stream_view stream=cuda_stream_view{})
	Allocates memory of size at least bytes. More...
void	deallocate (void *ptr, std::size_t bytes, cuda_stream_view stream=cuda_stream_view{})
	Deallocate memory pointed to by p. More...
bool	is_equal (device_memory_resource const &other) const noexcept
	Compare this resource to another. More...
void *	allocate (std::size_t bytes, std::size_t alignment)
	Allocates memory of size at least bytes. More...
void	deallocate (void *ptr, std::size_t bytes, std::size_t alignment)
	Deallocate memory pointed to by p. More...
void *	allocate_async (std::size_t bytes, std::size_t alignment, cuda_stream_view stream)
	Allocates memory of size at least bytes. More...
void *	allocate_async (std::size_t bytes, cuda_stream_view stream)
	Allocates memory of size at least bytes. More...
void	deallocate_async (void *ptr, std::size_t bytes, std::size_t alignment, cuda_stream_view stream)
	Deallocate memory pointed to by p. More...
void	deallocate_async (void *ptr, std::size_t bytes, cuda_stream_view stream)
	Deallocate memory pointed to by p. More...
bool	operator== (device_memory_resource const &other) const noexcept
	Comparison operator with another device_memory_resource. More...
bool	operator!= (device_memory_resource const &other) const noexcept
	Comparison operator with another device_memory_resource. More...

Static Public Attributes
static constexpr std::size_t	default_alignment_threshold = 0
	The default alignment used by the adaptor.

Detailed Description

template<typename Upstream>
class rmm::mr::aligned_resource_adaptor< Upstream >

Resource that adapts Upstream memory resource to allocate memory in a specified alignment size.

An instance of this resource can be constructed with an existing, upstream resource in order to satisfy allocation requests. This adaptor wraps allocations and deallocations from Upstream using the given alignment size.

By default, any address returned by one of the memory allocation routines from the CUDA driver or runtime API is always aligned to at least 256 bytes. For some use cases, such as GPUDirect Storage (GDS), allocations need to be aligned to a larger size (4 KiB for GDS) in order to avoid additional copies to bounce buffers.

Since a larger alignment size has some additional overhead, the user can specify a threshold size. If an allocation's size falls below the threshold, it is aligned to the default size. Only allocations with a size above the threshold are aligned to the custom alignment size.

Template Parameters

Upstream

Type of the upstream resource used for allocation/deallocation.

Constructor & Destructor Documentation

aligned_resource_adaptor() [1/2]

template<typename Upstream >

rmm::mr::aligned_resource_adaptor< Upstream >::aligned_resource_adaptor ( device_async_resource_ref  upstream, std::size_t  alignment = rmm::CUDA_ALLOCATION_ALIGNMENT, std::size_t  alignment_threshold = default_alignment_threshold  )

inlineexplicit

Construct an aligned resource adaptor using upstream to satisfy allocation requests.

Exceptions

rmm::logic_error

if allocation_alignment is not a power of 2

Parameters

upstream	The resource used for allocating/deallocating device memory.
alignment	The size used for allocation alignment.
alignment_threshold	Only allocations with a size larger than or equal to this threshold are aligned.

aligned_resource_adaptor() [2/2]

template<typename Upstream >

rmm::mr::aligned_resource_adaptor< Upstream >::aligned_resource_adaptor ( Upstream *  upstream, std::size_t  alignment = rmm::CUDA_ALLOCATION_ALIGNMENT, std::size_t  alignment_threshold = default_alignment_threshold  )

inlineexplicit

Construct an aligned resource adaptor using upstream to satisfy allocation requests.

Exceptions

rmm::logic_error	if upstream == nullptr
rmm::logic_error	if alignment is not a power of 2

Parameters

upstream	The resource used for allocating/deallocating device memory.
alignment	The size used for allocation alignment.
alignment_threshold	Only allocations with a size larger than or equal to this threshold are aligned.

Member Function Documentation

get_upstream_resource()

template<typename Upstream >

rmm::device_async_resource_ref rmm::mr::aligned_resource_adaptor< Upstream >::get_upstream_resource ( ) const

inlinenoexcept

rmm::device_async_resource_ref to the upstream resource

Returns

rmm::device_async_resource_ref to the upstream resource

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

• aligned_resource_adaptor.hpp