CudaHT::CuckooHashing::MultivalueHashTable Class Reference

Hash table that stores multiple values per key. More...

#include <hash_multivalue.h>

Inherits CudaHT::CuckooHashing::HashTable.

List of all members.

Public Member Functions
virtual bool	Build (const unsigned input_size, const unsigned *d_keys, const unsigned *d_vals)
	Build the multi-value hash table.
virtual void	Release ()
	Free all memory.
virtual void	Retrieve (const unsigned, const unsigned *, unsigned *)
	Don't call this.
virtual void	Retrieve (const unsigned n_queries, const unsigned *d_keys, uint2 *d_location_counts)
	Retrieve from a multi-value hash table.
const unsigned *	get_all_values () const
	Returns the array of values, where each key's values are stored contiguously in memory.
unsigned	get_values_size () const
	Gets the total number of values between all of the keys.
const uint2 *	get_index_counts () const
	Gets the location and number of values each key has.
virtual bool	Initialize (const unsigned max_input_size, const float space_usage=1.2, const unsigned num_functions=4)
	Initializes the multi-value hash table's memory.

---

Detailed Description

Hash table that stores multiple values per key.

A key with multiple values is represented by multiple key-value pairs in the input with the same key.

Querying the structure returns how many items the key has and its location in the array returned by get_all_values().

---

Member Function Documentation

bool CudaHT::CuckooHashing::MultivalueHashTable::Build	(	const unsigned	input_size,
		const unsigned *	d_keys,
		const unsigned *	d_vals
	)		[virtual]

Build the multi-value hash table.

See HashTable::Build() for an explanation of the parameters. Key-value pairs in the input with the same key are assumed to be values associated with the same key.

Parameters:

[in]	input_size	Number of key-value pairs being inserted.
[in]	d_keys	Device memory array containing all of the input keys.
[in]	d_vals	Device memory array containing the keys' values.

Returns:

Whether the hash table was built successfully (true) or not (false).

See also:

HashTable::Build()

Reimplemented from CudaHT::CuckooHashing::HashTable.

virtual void CudaHT::CuckooHashing::MultivalueHashTable::Retrieve	(	const unsigned	,
		const unsigned *	,
		unsigned *
	)		[inline, virtual]

Don't call this.

Todo:

Remove this function entirely somehow.

Reimplemented from CudaHT::CuckooHashing::HashTable.

void CudaHT::CuckooHashing::MultivalueHashTable::Retrieve	(	const unsigned	n_queries,
		const unsigned *	d_keys,
		uint2 *	d_location_counts
	)		[virtual]

Retrieve from a multi-value hash table.

Parameters:

[in]	n_queries	Number of queries in the input.
[in]	d_keys	Device mem: All of the query keys.
[out]	d_location_counts	Contains the index of a query key's first value and the number of values associated with the key. If a query fails, the number of values the key has will be marked as zero.

bool CudaHT::CuckooHashing::MultivalueHashTable::Initialize	(	const unsigned	max_input_size,
		const float	space_usage = 1.2,
		const unsigned	num_functions = 4
	)		[virtual]

Initializes the multi-value hash table's memory.

See HashTable::Initialize() for an explanation of the parameters.

Parameters:

[in]	max_input_size	Largest expected number of items in the input.
[in]	space_usage	Size of the hash table relative to the input. Bigger tables are faster to build and retrieve from.
[in]	num_functions	Number of hash functions to use. May be 2-5. More hash functions make it easier to build the table, but increase retrieval times.

Returns:

Whether the hash table was initialized successfully (true) or not (false).

See also:

HashTable::Initialize()

Reimplemented from CudaHT::CuckooHashing::HashTable.

---

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

• /mnt/hgfs/VMWare/cudpp/src/cudpp_hash/hash_multivalue.h
• /mnt/hgfs/VMWare/cudpp/src/cudpp_hash/hash_multivalue.cpp