__gnu_parallel::_Settings Struct Reference

#include <parallel/settings.h>

Public Member Functions
	_Settings ()

Static Public Member Functions
static _GLIBCXX_CONST const _Settings &	get () throw ()
	Get the global settings. More...
static void	set (_Settings &) throw ()
	Set the global settings. More...

Public Attributes
_AlgorithmStrategy	algorithm_strategy
_SortAlgorithm	sort_algorithm
_PartialSumAlgorithm	partial_sum_algorithm
_MultiwayMergeAlgorithm	multiway_merge_algorithm
_FindAlgorithm	find_algorithm
_SplittingAlgorithm	sort_splitting
_SplittingAlgorithm	merge_splitting
_SplittingAlgorithm	multiway_merge_splitting
_SequenceIndex	accumulate_minimal_n
	Minimal input size for accumulate. More...
unsigned int	adjacent_difference_minimal_n
	Minimal input size for adjacent_difference. More...
_SequenceIndex	count_minimal_n
	Minimal input size for count and count_if. More...
_SequenceIndex	fill_minimal_n
	Minimal input size for fill. More...
double	find_increasing_factor
	Block size increase factor for find. More...
_SequenceIndex	find_initial_block_size
	Initial block size for find. More...
_SequenceIndex	find_maximum_block_size
	Maximal block size for find. More...
_SequenceIndex	find_sequential_search_size
	Start with looking for this many elements sequentially, for find. More...
_SequenceIndex	for_each_minimal_n
	Minimal input size for for_each. More...
_SequenceIndex	generate_minimal_n
	Minimal input size for generate. More...
_SequenceIndex	max_element_minimal_n
	Minimal input size for max_element. More...
_SequenceIndex	merge_minimal_n
	Minimal input size for merge. More...
unsigned int	merge_oversampling
	Oversampling factor for merge. More...
_SequenceIndex	min_element_minimal_n
	Minimal input size for min_element. More...
_SequenceIndex	multiway_merge_minimal_n
	Minimal input size for multiway_merge. More...
int	multiway_merge_minimal_k
	Oversampling factor for multiway_merge. More...
unsigned int	multiway_merge_oversampling
	Oversampling factor for multiway_merge. More...
_SequenceIndex	nth_element_minimal_n
	Minimal input size for nth_element. More...
_SequenceIndex	partition_chunk_size
	Chunk size for partition. More...
double	partition_chunk_share
_SequenceIndex	partition_minimal_n
	Minimal input size for partition. More...
_SequenceIndex	partial_sort_minimal_n
	Minimal input size for partial_sort. More...
float	partial_sum_dilation
unsigned int	partial_sum_minimal_n
	Minimal input size for partial_sum. More...
unsigned int	random_shuffle_minimal_n
	Minimal input size for random_shuffle. More...
_SequenceIndex	replace_minimal_n
	Minimal input size for replace and replace_if. More...
_SequenceIndex	set_difference_minimal_n
	Minimal input size for set_difference. More...
_SequenceIndex	set_intersection_minimal_n
	Minimal input size for set_intersection. More...
_SequenceIndex	set_symmetric_difference_minimal_n
	Minimal input size for set_symmetric_difference. More...
_SequenceIndex	set_union_minimal_n
	Minimal input size for set_union. More...
_SequenceIndex	sort_minimal_n
	Minimal input size for parallel sorting. More...
unsigned int	sort_mwms_oversampling
	Oversampling factor for parallel std::sort (MWMS). More...
unsigned int	sort_qs_num_samples_preset
	Such many samples to take to find a good pivot (quicksort). More...
_SequenceIndex	sort_qsb_base_case_maximal_n
_SequenceIndex	transform_minimal_n
	Minimal input size for parallel std::transform. More...
_SequenceIndex	unique_copy_minimal_n
	Minimal input size for unique_copy. More...
_SequenceIndex	workstealing_chunk_size
unsigned long long	L1_cache_size
	size of the L1 cache in bytes (underestimation). More...
unsigned long long	L2_cache_size
	size of the L2 cache in bytes (underestimation). More...
unsigned int	TLB_size
	size of the Translation Lookaside Buffer (underestimation). More...
unsigned int	cache_line_size
_SequenceIndex	qsb_steals
	The number of stolen ranges in load-balanced quicksort. More...
_SequenceIndex	search_minimal_n
	Minimal input size for search and search_n. More...
float	find_scale_factor
	Block size scale-down factor with respect to current position. More...

Detailed Description

class _Settings Run-time settings for the parallel mode including all tunable parameters.

Constructor & Destructor Documentation

__gnu_parallel::_Settings::_Settings ( )

inlineexplicit

                :
            algorithm_strategy(heuristic),
            sort_algorithm(MWMS),
            partial_sum_algorithm(LINEAR),
            multiway_merge_algorithm(LOSER_TREE),
            find_algorithm(CONSTANT_SIZE_BLOCKS),
            sort_splitting(EXACT),
            merge_splitting(EXACT),
            multiway_merge_splitting(EXACT),
            accumulate_minimal_n(1000),
            adjacent_difference_minimal_n(1000),
            count_minimal_n(1000),
            fill_minimal_n(1000),
            find_increasing_factor(2.0),
            find_initial_block_size(256),
            find_maximum_block_size(8192),
            find_sequential_search_size(256),
            for_each_minimal_n(1000),
            generate_minimal_n(1000),
            max_element_minimal_n(1000),
            merge_minimal_n(1000),
            merge_oversampling(10),
            min_element_minimal_n(1000),
            multiway_merge_minimal_n(1000),
            multiway_merge_minimal_k(2), multiway_merge_oversampling(10),
            nth_element_minimal_n(1000),
            partition_chunk_size(1000),
            partition_chunk_share(0.0),
            partition_minimal_n(1000),
            partial_sort_minimal_n(1000),
            partial_sum_dilation(1.0f),
            partial_sum_minimal_n(1000),
            random_shuffle_minimal_n(1000),
            replace_minimal_n(1000),
            set_difference_minimal_n(1000),
            set_intersection_minimal_n(1000),
            set_symmetric_difference_minimal_n(1000),
            set_union_minimal_n(1000),
            sort_minimal_n(1000),
            sort_mwms_oversampling(10),
            sort_qs_num_samples_preset(100),
            sort_qsb_base_case_maximal_n(100),
            transform_minimal_n(1000),
            unique_copy_minimal_n(10000),
            workstealing_chunk_size(100),
            L1_cache_size(16 << 10),
            L2_cache_size(256 << 10),
            TLB_size(128),
            cache_line_size(64),
            qsb_steals(0),
            search_minimal_n(1000),
            find_scale_factor(0.01f)
    { }

Member Function Documentation

static _GLIBCXX_CONST const _Settings& __gnu_parallel::_Settings::get ( ) throw ( )

static

Get the global settings.

static void __gnu_parallel::_Settings::set ( _Settings &  ) throw ( )

static

Set the global settings.

Member Data Documentation

_SequenceIndex __gnu_parallel::_Settings::accumulate_minimal_n

Minimal input size for accumulate.

unsigned int __gnu_parallel::_Settings::adjacent_difference_minimal_n

Minimal input size for adjacent_difference.

_AlgorithmStrategy __gnu_parallel::_Settings::algorithm_strategy

unsigned int __gnu_parallel::_Settings::cache_line_size

Overestimation of cache line size. Used to avoid false sharing, i.e. elements of different threads are at least this amount apart.

_SequenceIndex __gnu_parallel::_Settings::count_minimal_n

Minimal input size for count and count_if.

_SequenceIndex __gnu_parallel::_Settings::fill_minimal_n

Minimal input size for fill.

_FindAlgorithm __gnu_parallel::_Settings::find_algorithm

double __gnu_parallel::_Settings::find_increasing_factor

Block size increase factor for find.

_SequenceIndex __gnu_parallel::_Settings::find_initial_block_size

Initial block size for find.

_SequenceIndex __gnu_parallel::_Settings::find_maximum_block_size

Maximal block size for find.

float __gnu_parallel::_Settings::find_scale_factor

Block size scale-down factor with respect to current position.

_SequenceIndex __gnu_parallel::_Settings::find_sequential_search_size

Start with looking for this many elements sequentially, for find.

_SequenceIndex __gnu_parallel::_Settings::for_each_minimal_n

Minimal input size for for_each.

_SequenceIndex __gnu_parallel::_Settings::generate_minimal_n

Minimal input size for generate.

unsigned long long __gnu_parallel::_Settings::L1_cache_size

size of the L1 cache in bytes (underestimation).

unsigned long long __gnu_parallel::_Settings::L2_cache_size

size of the L2 cache in bytes (underestimation).

_SequenceIndex __gnu_parallel::_Settings::max_element_minimal_n

Minimal input size for max_element.

_SequenceIndex __gnu_parallel::_Settings::merge_minimal_n

Minimal input size for merge.

unsigned int __gnu_parallel::_Settings::merge_oversampling

Oversampling factor for merge.

_SplittingAlgorithm __gnu_parallel::_Settings::merge_splitting

_SequenceIndex __gnu_parallel::_Settings::min_element_minimal_n

Minimal input size for min_element.

_MultiwayMergeAlgorithm __gnu_parallel::_Settings::multiway_merge_algorithm

int __gnu_parallel::_Settings::multiway_merge_minimal_k

Oversampling factor for multiway_merge.

_SequenceIndex __gnu_parallel::_Settings::multiway_merge_minimal_n

Minimal input size for multiway_merge.

unsigned int __gnu_parallel::_Settings::multiway_merge_oversampling

Oversampling factor for multiway_merge.

_SplittingAlgorithm __gnu_parallel::_Settings::multiway_merge_splitting

_SequenceIndex __gnu_parallel::_Settings::nth_element_minimal_n

Minimal input size for nth_element.

_SequenceIndex __gnu_parallel::_Settings::partial_sort_minimal_n

Minimal input size for partial_sort.

_PartialSumAlgorithm __gnu_parallel::_Settings::partial_sum_algorithm

float __gnu_parallel::_Settings::partial_sum_dilation

Ratio for partial_sum. Assume "sum and write result" to be this factor slower than just "sum".

unsigned int __gnu_parallel::_Settings::partial_sum_minimal_n

Minimal input size for partial_sum.

double __gnu_parallel::_Settings::partition_chunk_share

Chunk size for partition, relative to input size. If > 0.0, this value overrides partition_chunk_size.

_SequenceIndex __gnu_parallel::_Settings::partition_chunk_size

Chunk size for partition.

_SequenceIndex __gnu_parallel::_Settings::partition_minimal_n

Minimal input size for partition.

_SequenceIndex __gnu_parallel::_Settings::qsb_steals

The number of stolen ranges in load-balanced quicksort.

unsigned int __gnu_parallel::_Settings::random_shuffle_minimal_n

Minimal input size for random_shuffle.

_SequenceIndex __gnu_parallel::_Settings::replace_minimal_n

Minimal input size for replace and replace_if.

_SequenceIndex __gnu_parallel::_Settings::search_minimal_n

Minimal input size for search and search_n.

_SequenceIndex __gnu_parallel::_Settings::set_difference_minimal_n

Minimal input size for set_difference.

_SequenceIndex __gnu_parallel::_Settings::set_intersection_minimal_n

Minimal input size for set_intersection.

_SequenceIndex __gnu_parallel::_Settings::set_symmetric_difference_minimal_n

Minimal input size for set_symmetric_difference.

_SequenceIndex __gnu_parallel::_Settings::set_union_minimal_n

Minimal input size for set_union.

_SortAlgorithm __gnu_parallel::_Settings::sort_algorithm

_SequenceIndex __gnu_parallel::_Settings::sort_minimal_n

Minimal input size for parallel sorting.

unsigned int __gnu_parallel::_Settings::sort_mwms_oversampling

Oversampling factor for parallel std::sort (MWMS).

unsigned int __gnu_parallel::_Settings::sort_qs_num_samples_preset

Such many samples to take to find a good pivot (quicksort).

_SequenceIndex __gnu_parallel::_Settings::sort_qsb_base_case_maximal_n

Maximal subsequence __length to switch to unbalanced __base case. Applies to std::sort with dynamically load-balanced quicksort.

_SplittingAlgorithm __gnu_parallel::_Settings::sort_splitting

unsigned int __gnu_parallel::_Settings::TLB_size

size of the Translation Lookaside Buffer (underestimation).

_SequenceIndex __gnu_parallel::_Settings::transform_minimal_n

Minimal input size for parallel std::transform.

_SequenceIndex __gnu_parallel::_Settings::unique_copy_minimal_n

Minimal input size for unique_copy.

_SequenceIndex __gnu_parallel::_Settings::workstealing_chunk_size

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

• GCC4/inc/parallel/settings.h