static object _lock = new object();
    public static void _main()
    {
            lock (_lock)
            {
                _bulkcopy(myData);
            }
    }
    public static void _bulkcopy(DataTable dt)
    {
        try
        {
            using (var connection = new SqlConnection(ConfigurationSettings.AppSettings.Get("DBConnection")))
            {
                connection.Open();
                SqlTransaction transaction = connection.BeginTransaction();

                using (var bulkCopy = new SqlBulkCopy(connection, SqlBulkCopyOptions.Default, transaction))
                {
                    bulkCopy.BatchSize = 100;
                bulkCopy.BulkCopyTimeout = 100; //default 30
                    bulkCopy.DestinationTableName = "dbo.MyTable";
                    try
                    {
                        bulkCopy.WriteToServer(dt);
                    }
                    catch (Exception)
                    {
                        transaction.Rollback();
                        connection.Close();
                    }
                }

                transaction.Commit();
            }

        }
        catch { }
    }