Description of an object's content. More...

#include <content_description.hpp>

Public Types
enum class	Spillable : bool { NO , YES }
	Indicates whether the content is spillable.

Public Member Functions
template<std::ranges::input_range Range = std::initializer_list<std::pair<MemoryType, std::size_t>>>
requires constexpr std::convertible_to< std::ranges::range_value_t< Range >, std::pair< MemoryType, std::size_t > >	ContentDescription (Range &&sizes, Spillable spillable)
	Construct a content description from a range of (MemoryType, size) pairs. More...

constexpr	ContentDescription (Spillable spillable=Spillable::NO)
	Construct a description with all sizes zero and a given spillability. More...

constexpr std::size_t &	content_size (MemoryType mem_type) noexcept
	Access (read/write) the size for a specific memory type. More...

constexpr std::size_t	content_size (MemoryType mem_type) const noexcept
	Get the size for a specific memory type. More...

constexpr MemoryType	principal_memory_type () const noexcept
	Returns the principal memory type of the content. More...

constexpr std::size_t	content_size () const noexcept
	Get the total content size across all memory types. More...

constexpr bool	spillable () const noexcept

constexpr bool	operator== (ContentDescription const &other) const noexcept
	Equality comparison. More...

Detailed Description

Description of an object's content.

A ContentDescription encapsulates resource-related information about an object's content such as memory sizes, memory types, and spillability.

In RapidsMPF, an object's content refers to the actual data associated with the object, not its metadata or auxiliary information. Typically, this content is represented by one or more Buffer instances that may reside in different memory spaces (e.g., host or device). It is also this content that is subject to spilling and that typically accounts for the majority of an object's overall memory footprint.

The spillability state of an object is treated as an all-or-nothing property. While one could imagine an object with a mix of spillable and non-spillable content, this distinction is intentionally simplified in RapidsMPF.

Definition at line 32 of file content_description.hpp.

Constructor & Destructor Documentation

◆ ContentDescription() [1/2]

template<std::ranges::input_range Range = std::initializer_list<std::pair<MemoryType, std::size_t>>>

requires constexpr std::convertible_to< std::ranges::range_value_t<Range>, std::pair<MemoryType, std::size_t> > rapidsmpf::ContentDescription::ContentDescription	(	Range &&	sizes,
		Spillable	spillable
	)

inlineexplicitconstexpr

Construct a content description from a range of (MemoryType, size) pairs.

Memory types omitted from the input are initialized to zero.

Template Parameters

Range A range whose value type is convertible to std::pair<MemoryType, std::size_t>.

Parameters

sizes	Range of (MemoryType, size) pairs representing content sizes.
spillable	Whether the content is spillable to slower memory tiers.

ContentDescription desc{
    std::array{
        std::pair{MemoryType::HOST,   1024UL},
        std::pair{MemoryType::DEVICE, 2048UL}
    },
    ContentDescription::Spillable::YES
};

Definition at line 66 of file content_description.hpp.

◆ ContentDescription() [2/2]

constexpr rapidsmpf::ContentDescription::ContentDescription ( Spillable spillable = Spillable::NO )

inlineconstexpr

Construct a description with all sizes zero and a given spillability.

Useful when you need a zero-sized content description or when building a content description iteratively.

Parameters

spillable Whether the content are spillable.

Definition at line 85 of file content_description.hpp.

Member Function Documentation

◆ content_size() [1/3]

constexpr std::size_t rapidsmpf::ContentDescription::content_size ( ) const

inlineconstexprnoexcept

Get the total content size across all memory types.

Computes the sum of all per-memory-type content sizes. This represents the total size (in bytes) of the object's content across host, device, and any other memory types.

Returns: Total size (in bytes) across all memory types.

Definition at line 141 of file content_description.hpp.

◆ content_size() [2/3]

constexpr std::size_t rapidsmpf::ContentDescription::content_size ( MemoryType mem_type ) const

inlineconstexprnoexcept

Get the size for a specific memory type.

Parameters

mem_type The memory type entry to access.

Returns: Size (in bytes) for the given memory type.

Definition at line 104 of file content_description.hpp.

◆ content_size() [3/3]

constexpr std::size_t& rapidsmpf::ContentDescription::content_size ( MemoryType mem_type )

inlineconstexprnoexcept

Access (read/write) the size for a specific memory type.

Parameters

mem_type The memory type entry to access.

Returns: Reference to the size (in bytes) for the given memory type.

Definition at line 94 of file content_description.hpp.

◆ operator==()

constexpr bool rapidsmpf::ContentDescription::operator== ( ContentDescription const & other ) const

inlineconstexprnoexcept

Equality comparison.

Parameters

other The content description to compare against.

Returns: true if both descriptions are equal; otherwise false.

Definition at line 158 of file content_description.hpp.

◆ principal_memory_type()

constexpr MemoryType rapidsmpf::ContentDescription::principal_memory_type ( ) const

inlineconstexprnoexcept

Returns the principal memory type of the content.

The principal memory type is the first memory type with non-zero content, evaluated in the preference order defined by MEMORY_TYPES.

If all content sizes are zero, the method returns MemoryType::DEVICE. Zero-sized content usually means the Message contains only metadata, or that the content size is unknown or irrelevant. In such cases the choice of memory type has no practical effect. We default to MemoryType::DEVICE because, when spillable() == false, it is the only memory type that meaningfully applies.

Returns: The first memory type with non-zero content, or MemoryType::DEVICE if none contain content.

Definition at line 123 of file content_description.hpp.

◆ spillable()

constexpr bool rapidsmpf::ContentDescription::spillable ( ) const

inlineconstexprnoexcept

Returns: Whether the content can be spilled.

Definition at line 148 of file content_description.hpp.

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

/__w/rapidsmpf/rapidsmpf/cpp/include/rapidsmpf/memory/content_description.hpp

Public Types

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ ContentDescription() [1/2]

◆ ContentDescription() [2/2]

Member Function Documentation

◆ content_size() [1/3]

◆ content_size() [2/3]

◆ content_size() [3/3]

◆ operator==()

◆ principal_memory_type()

◆ spillable()