anchor.diff:      Parallel = randoms:rand_uniform(1, 50),
       Count = 10000 div Parallel,
       WriteFun = fun(_I) -> ok = gcounter_on_cseq:inc(Key) end,
  -    spawn_writers(UnitTestPid, Parallel, Count, WriteFun),
  +    _ = spawn_writers(UnitTestPid, Parallel, Count, WriteFun),
       wait_writers_completion(Parallel),
   
       {ok, Result} = gcounter_on_cseq:read(Key),
  
positive.code:                     ok = pncounter_on_cseq:subtract(From, TransactAmount),
                      ok = pncounter_on_cseq:add(To, TransactAmount)
                  end,
      spawn_writers(UnitTestPid, Parallel, Count, WriteFun),
      wait_writers_completion(Parallel),
  
      %% check if nothing is lost or gained
  
negative.code:                                             true -> ok;
                                              false ->
                                                  ct:pal("~n~w ~nis not smaller or equals than ~n~w", [Prev, Result]),
                                                  UnitTestPid ! {compare_failed, Prev, Result},
                                                  ok
                                          end,
                                          NextReader = lists:nth(randoms:rand_uniform(1, length(Pids)+1), Pids),
                                          NextReader ! {read, Pids, Result},
                                          ok
                                  end,
                                  F(F)
                              end,
  