libgit2sharp: Why Pull operations is so Slow?

Hi all, I’m new and I’m developing using this library. I have some problem with pull operations. This is my code:

 Debug.Write("Pulling branch. . .");
            LibGit2Sharp.PullOptions options = new LibGit2Sharp.PullOptions();
            options.FetchOptions = new FetchOptions();
            options.FetchOptions.CredentialsProvider = new CredentialsHandler(
                (url, usernameFromUrl, types) =>
                    new UsernamePasswordCredentials()
                    {
                        Username = this.Username,
                        Password = this.Password
                    });
            Signature author = new Signature(this.Username, this.EmailUser, DateTime.Now);
            Commands.Pull(Repo, author, options);
            Debug.Write("Pulling done.");

I don’t uderstand why Pulling ONE FILE (txt 1kb) is so SLOW. Is there anyone help me?