memgraph/tests/concurrent/sl_memory_leak.cpp

#include "common.hpp"

constexpr size_t THREADS_NO = std::min(max_no_threads, 1);
constexpr size_t elems_per_thread = 16e5;

// TODO: Memory leak at 1,600,000 elements (Kruno wrote this here but
// the memory_check method had invalid implementation)
//     1. implement valid memory_check
//     2. analyse this code
//     3. fix the memory leak
//     4. write proper test
int main(int, char **argv) {
  google::InitGoogleLogging(argv[0]);

  memory_check(THREADS_NO, [&] {
    std::vector<std::thread> threads;
    map_t skiplist;

    // put THREADS_NO * elems_per_thread items to the skiplist
    for (size_t thread_i = 0; thread_i < THREADS_NO; ++thread_i) {
      threads.emplace_back(
          [&skiplist](size_t start, size_t end) {
            auto accessor = skiplist.access();
            for (size_t elem_i = start; elem_i < end; ++elem_i) {
              accessor.insert(elem_i, elem_i);
            }
          },
          thread_i * elems_per_thread,
          thread_i * elems_per_thread + elems_per_thread);
    }
    // wait all threads
    for (auto &thread : threads) {
      thread.join();
    }

    // get skiplist size
    {
      auto accessor = skiplist.access();
      permanent_assert(accessor.size() == THREADS_NO * elems_per_thread,
                       "all elements in skiplist");
    }

    for (size_t thread_i = 0; thread_i < THREADS_NO; ++thread_i) {
      threads[thread_i] = std::thread(
          [&skiplist](size_t start, size_t end) {
            auto accessor = skiplist.access();
            for (size_t elem_i = start; elem_i < end; ++elem_i) {
              permanent_assert(accessor.remove(elem_i) == true, "");
            }
          },
          thread_i * elems_per_thread,
          thread_i * elems_per_thread + elems_per_thread);
    }
    // // wait all threads
    for (auto &thread : threads) {
      thread.join();
    }

    // check size
    {
      auto accessor = skiplist.access();
      permanent_assert(accessor.size() == 0, "Size should be 0, but size is "
                                                 << accessor.size());
    }

    // check count
    {
      size_t iterator_counter = 0;
      auto accessor = skiplist.access();
      for (auto elem : accessor) {
        ++iterator_counter;
        cout << elem.first << " ";
      }
      permanent_assert(iterator_counter == 0, "deleted elements");
    }
  });
}