Comments by PhaazeReborn (Top 4 by date)

constexpr std::size_t small_size{ 4036 };
constexpr std::size_t large_size{ 1'000'000 };

struct SmallBucket
{
    const static std::size_t data_size{ small_size };
    std::byte data[data_size];
};

struct LargeBucket
{
    using byte = std::byte;

    const static std::size_t data_size{ large_size };
    byte data[data_size];
};

struct Heap
{
    void* allocate(std::size_t bytes)
    {
        if (bytes >= 1 && bytes <= SmallBucket::data_size) {

            for (int i{}; i < n_heap_buckets; ++i) {

                if (!buckets_used[i])
                {
                    buckets_used[i] = true;
                    return large_buckets[i].data;
                }
            }
        }
        else if (bytes > SmallBucket::data_size && bytes <= LargeBucket::data_size) {

            for (int i{}; i < n_heap_buckets; ++i) {

                if (!buckets_used[i])
                {
                    buckets_used[i] = true;
                    return small_buckets[i].data;
                }
            }
        }

        throw std::bad_alloc{};
    }

    void free(void* p)
    {
        for (std::size_t i{}; i < n_heap_buckets; ++i)
        {
            if (large_buckets[i].data == p)
            {
                buckets_used[i] = false;
                return;
            }
        }
    }

    const static std::size_t  n_heap_buckets{ 10 };
    SmallBucket small_buckets[n_heap_buckets];
    LargeBucket large_buckets[n_heap_buckets];
    bool buckets_used[n_heap_buckets];
};

Heap heap;

void* operator new(std::size_t n_bytes)
{
    return heap.allocate(n_bytes);
}

void operator delete(void* p)
{
    heap.free(p);
}