A library to scatter things accross a cluster depending on weights
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#pragma once
#include <stdint.h>
#include "9float.hpp"
using scatter_key_t = ninefloat::Q<__int128,64>;
static const scatter_key_t scatter_key_increment = ninefloat::Q<__int128,64>::min_increment();
#include <vector>
#include <numeric>
#include <type_traits>
#include <iostream>
namespace StorageTree {
namespace _impl {
template<class childs>
struct subdivision {
uint64_t weight;
std::vector<childs> content;
scatter_key_t begin;
scatter_key_t end;
static constexpr bool divisible = true;
};
struct daemon_impl {
uint64_t weight;
scatter_key_t begin;
scatter_key_t end;
static constexpr bool divisible = false;
};
template<class T>
constexpr T max(T any = 0)
{
if(any>any+scatter_key_increment) {
return any;
}
return max(any+scatter_key_increment);
}
}
using daemon = _impl::daemon_impl;
using server = _impl::subdivision<daemon>;
using subrack = _impl::subdivision<server>;
using rack = _impl::subdivision<subrack>;
using room = _impl::subdivision<rack>;
using datacenter = _impl::subdivision<room>;
using root = _impl::subdivision<datacenter>;
template<class T>
uint64_t total_weight(T& root)
{
uint64_t ret=0;
for(auto& val : root.content) {
ret+=total_weight(val);
}
return ret;
}
template<>
uint64_t total_weight<daemon>(daemon& root)
{
return root.weight;
}
template<class T>
scatter_key_t update_weights(T& root, uint64_t total, double sub_ratio=1, scatter_key_t begin=0, double ratio=0.5)
{
auto b = begin;
for(auto& elem : root.content) {
std::cout<<"UP"<<std::endl;
b = update_weights(
elem,
total,
sub_ratio*root.content.size(),
b,
ratio
)+scatter_key_increment;
}
return begin;
}
template<>
scatter_key_t update_weights<daemon>(daemon& root, uint64_t total, double sub_ratio, scatter_key_t begin, double ratio)
{
root.begin = begin;
root.end = begin+scatter_key_t(0.5)*((scatter_key_t(1/sub_ratio)*scatter_key_t(ratio)+scatter_key_t((double)root.weight/(double)total)*scatter_key_t(1-ratio)));
std::cout<<"Starts: "<<(uint64_t)root.begin.data()<<" Ends: "<<(uint64_t)root.end.data()<<std::endl;
return root.end;
}
template<class T, typename... Args>
void add_rule(T& root, uint64_t weight, size_t idx, std::tuple<Args...> Var)
{
if(idx<root.content.size())
add_rule(root.content.at(idx),weight,Var...);
else if(idx==root.content.size())
{
root.content.emplace_back();
add_rule(root.content.at(idx),weight,Var...);
}
else
throw std::runtime_error("libscatter: Bad rule, are you sure the order is right?");
}
template<>
void add_rule<daemon,size_t>(daemon& root, uint64_t weight,std::tuple<>)
{
root.weight=weight;
}
}