rapidsmpf::streaming::BloomFilter Struct Reference

Utility managing construction and use of a bloom filter. More...

#include <bloom_filter.hpp>

Public Member Functions
	BloomFilter (std::shared_ptr< Context > ctx, std::shared_ptr< Communicator > comm, std::uint64_t seed, std::size_t num_filter_blocks) noexcept
	Construct storage for a bloom filter. More...
std::shared_ptr< Communicator > const &	comm () const noexcept
	Gets the communicator associated with this BloomFilter. More...
Actor	build (std::shared_ptr< Channel > ch_in, std::shared_ptr< Channel > ch_out, OpID tag)
	Build a bloom filter from the input channel. More...
Actor	apply (std::shared_ptr< Channel > bloom_filter, std::shared_ptr< Channel > ch_in, std::shared_ptr< Channel > ch_out, std::vector< cudf::size_type > keys)
	Apply a bloom filter to an input channel. More...

Detailed Description

Utility managing construction and use of a bloom filter.

This class provides methods to build a bloom filter from a stream of TableChunks and then apply that filter to a different stream.

A bloom filter is a fixed size probabilistic data structure that provides approximate set membership queries with no false negatives. That is, let A be some set and f(A) be the bloom filter representation of that set. Then, for all a ∈ A it holds that a ∈ f(A). Conversely, there is a false positive rate that increases with the number of distinct values inserted into the bloom filter, and decreases with the number of filter blocks. That is, for any given bloom filter, there exists a ∉ A such that a ∈ f(A).

See https://arxiv.org/pdf/2512.15595 for details on the GPU implementation used.

We use bloom filters to provide runtime pre-filtering of tables during shuffle-based joins. We gather the keys that will match from the build side and use those to pre-filter the probe side before shuffling.

Definition at line 38 of file bloom_filter.hpp.

Constructor & Destructor Documentation

BloomFilter()

rapidsmpf::streaming::BloomFilter::BloomFilter ( std::shared_ptr< Context >  ctx, std::shared_ptr< Communicator >  comm, std::uint64_t  seed, std::size_t  num_filter_blocks  )

inlineexplicitnoexcept

Construct storage for a bloom filter.

Parameters

ctx	Streaming context.
comm	Communicator for the collective operation.
seed	Hash seed used when hashing values into the filter.
num_filter_blocks	Number of blocks in the filter.

Definition at line 47 of file bloom_filter.hpp.

Member Function Documentation

apply()

Actor rapidsmpf::streaming::BloomFilter::apply	(	std::shared_ptr< Channel >	bloom_filter,
		std::shared_ptr< Channel >	ch_in,
		std::shared_ptr< Channel >	ch_out,
		std::vector< cudf::size_type >	keys
	)

Apply a bloom filter to an input channel.

Parameters

bloom_filter	Channel containing the bloom filter (a single message).
ch_in	Input channel of TableChunks to apply bloom filter to.
ch_out	Output channel receiving filtered TableChunks.
keys	Indices selecting the key columns for the hash fingerprint

Note

The application of the bloom filter expects exactly one message to come through the bloom_filter channel, which must be drained after that message is sent.

Returns

Coroutine representing the application of the bloom filter.

build()

Actor rapidsmpf::streaming::BloomFilter::build	(	std::shared_ptr< Channel >	ch_in,
		std::shared_ptr< Channel >	ch_out,
		OpID	tag
	)

Build a bloom filter from the input channel.

Parameters

ch_in	Input channel of TableChunks to build bloom filter for.
ch_out	Output channel receiving a single message containing the bloom filter.
tag	Disambiguating tag to combine filters across ranks.

Returns

Coroutine representing the construction of the bloom filter.

comm()

std::shared_ptr<Communicator> const& rapidsmpf::streaming::BloomFilter::comm ( ) const

inlinenoexcept

Gets the communicator associated with this BloomFilter.

Returns

Shared pointer to communicator.

Definition at line 63 of file bloom_filter.hpp.

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

• /__w/rapidsmpf/rapidsmpf/cpp/include/rapidsmpf/streaming/cudf/bloom_filter.hpp