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///
/// @file LoadBalancerAC.hpp
/// @brief This load balancer assigns work to the threads in the
/// computation of the A & C formulas (AC.cpp) in
/// Xavier Gourdon's algorithm.
///
/// Load balancing is described in more detail at:
/// https://github.com/kimwalisch/primecount/blob/master/doc/Easy-Special-Leaves.md
///
/// Copyright (C) 2025 Kim Walisch, <kim.walisch@gmail.com>
///
/// This file is distributed under the BSD License. See the COPYING
/// file in the top level directory.
///
#ifndef LOADBALANCERAC_HPP
#define LOADBALANCERAC_HPP
#include <OmpLock.hpp>
#include <stdint.h>
#include <cstddef>
namespace primecount {
struct ThreadDataAC
{
int64_t low = 0;
int64_t segments = 0;
int64_t segment_size = 0;
double secs = 0;
};
class LoadBalancerAC
{
public:
LoadBalancerAC(int64_t sqrtx, int64_t y, int threads, bool is_print);
bool get_work(ThreadDataAC& thread);
private:
void print_status(double current_time);
int64_t low_ = 0;
int64_t sqrtx_ = 0;
int64_t y_ = 0;
int64_t segments_ = 0;
int64_t segment_size_ = 0;
int64_t segment_nr_ = 0;
int64_t max_segment_size_ = 0;
std::size_t prev_status_size_ = 0;
double start_time_ = 0;
double print_time_ = 0;
int threads_ = 0;
bool is_print_ = false;
OmpLock lock_;
};
} // namespace
#endif
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