thread.hpp File Reference

#include "barretenberg/common/compiler_hints.hpp"
#include <atomic>
#include <barretenberg/env/hardware_concurrency.hpp>
#include <barretenberg/numeric/bitop/get_msb.hpp>
#include <functional>
#include <iostream>
#include <vector>

Go to the source code of this file.

Classes
struct	bb::MultithreadData

Namespaces
namespace	bb
	Entry point for Barretenberg command-line interface.
namespace	bb::thread_heuristics

Functions
size_t	bb::get_num_cpus ()
size_t	bb::get_num_cpus_pow2 ()
void	bb::parallel_for (size_t num_iterations, const std::function< void(size_t)> &func)
void	bb::parallel_for_range (size_t num_points, const std::function< void(size_t, size_t)> &func, size_t no_multhreading_if_less_or_equal)
	Split a loop into several loops running in parallel.
void	bb::parallel_for_heuristic (size_t num_points, const std::function< void(size_t, size_t, size_t)> &func, size_t heuristic_cost)
	Split a loop into several loops running in parallel based on operations in 1 iteration.
template<typename Func > requires std::invocable<Func, std::size_t>
void	bb::parallel_for_heuristic (size_t num_points, const Func &func, size_t heuristic_cost)
template<typename Func , typename Accum > requires std::invocable<Func, std::size_t, Accum&>
std::vector< Accum >	bb::parallel_for_heuristic (size_t num_points, const Accum &initial_accum, const Func &func, size_t heuristic_cost)
	parallel_for_heuristic variant that takes an accumulator initializer that is allocated in a vector, one accumulator per thread/chunk. This allows for thread-safe accumulation, see sum() or sum_pairs() in container.hpp for an easy way to combine the thread/chunk contributions into a final result.
MultithreadData	bb::calculate_thread_data (size_t num_iterations, size_t min_iterations_per_thread=DEFAULT_MIN_ITERS_PER_THREAD)
	Calculates number of threads and index bounds for each thread.
size_t	bb::calculate_num_threads (size_t num_iterations, size_t min_iterations_per_thread)
	calculates number of threads to create based on minimum iterations per thread
size_t	bb::calculate_num_threads_pow2 (size_t num_iterations, size_t min_iterations_per_thread)
	calculates number of threads to create based on minimum iterations per thread, guaranteed power of 2

Variables
const size_t	bb::DEFAULT_MIN_ITERS_PER_THREAD = 1 << 4
constexpr size_t	bb::thread_heuristics::FF_ADDITION_COST = 4
constexpr size_t	bb::thread_heuristics::FF_MULTIPLICATION_COST = 21
constexpr size_t	bb::thread_heuristics::FF_INVERSION_COST = 7000
constexpr size_t	bb::thread_heuristics::GE_ADDITION_COST = 350
constexpr size_t	bb::thread_heuristics::GE_DOUBLING_COST = 194
constexpr size_t	bb::thread_heuristics::SM_COST = 50000
constexpr size_t	bb::thread_heuristics::FF_COPY_COST = 3
constexpr size_t	bb::thread_heuristics::ALWAYS_MULTITHREAD = 100000