Files
scylladb/tests/allocator_test.cc
2014-11-20 12:37:18 +02:00

76 lines
1.9 KiB
C++

/*
* Copyright 2014 Cloudius Systems
*/
#include <random>
#include <cmath>
#include <iostream>
#include <iomanip>
#include <algorithm>
#include <cassert>
#include <memory>
struct allocation {
size_t n;
std::unique_ptr<char[]> data;
char poison;
allocation(size_t n, char poison) : n(n), data(new char[n]), poison(poison) {
std::fill_n(data.get(), n, poison);
}
~allocation() {
verify();
}
allocation(allocation&& x) noexcept = default;
void verify() {
if (data) {
assert(std::find_if(data.get(), data.get() + n, [this] (char c) {
return c != poison;
}) == data.get() + n);
}
}
allocation& operator=(allocation&& x) {
verify();
if (this != &x) {
data = std::move(x.data);
n = x.n;
poison = x.poison;
}
return *this;
}
};
int main(int ac, char** av) {
std::default_random_engine random_engine;
std::exponential_distribution<> distr(0.2);
std::uniform_int_distribution<> type(0, 1);
std::uniform_int_distribution<char> poison(-128, 127);
std::uniform_real_distribution<> which(0, 1);
std::vector<allocation> allocations;
for (auto i = 0; i < 200000; ++i) {
auto typ = type(random_engine);
switch (typ) {
case 0: {
auto n = std::min<size_t>(std::exp(distr(random_engine)), 1 << 25);
try {
allocations.emplace_back(n, poison(random_engine));
} catch (std::bad_alloc&) {
}
break;
}
case 1: {
if (allocations.empty()) {
continue;
}
size_t i = which(random_engine) * allocations.size();
allocations[i] = std::move(allocations.back());
allocations.pop_back();
break;
}
}
}
return 0;
}