问PostgreSQL:负载测试引发错误-- Npgsql.PostgresException：“53300:对不起，已经有太多客户端了”

EN

            List<Values> values = new List<Values>();

            for (int i = 0; i < 200; i++)
            {
                var mythread = new Thread(() =>
                {
                    DatabaseConnection db = new DatabaseConnection();
                    using (var conn = db.GetDatabaseConnection())
                    {
                        var cmd = new NpgsqlCommand();
                        cmd.Connection = conn;
                        cmd.CommandText = "SELECT val.id, val.name FROM val.myvalue val";
                        cmd.Prepare();
                        var reader = cmd.ExecuteReader();
                        try
                        {
                            while (reader.Read())
                            {
                                Values value = new Values();
                                value.Id = reader.GetInt64(0);
                                value.Name = reader.GetString(1);

                                values.Add(value);
                            }
                            reader.Close();
                        }
                        catch (Exception ex)
                        {
                            reader.Close();
                            var exception = ex;
                            throw exception;
                        }
                    }
                });

                mythread.Start();
            }

public class DatabaseConnection
{
    public NpgsqlConnection GetDatabaseConnection()
    {
        var connectionstring = "User ID=myuser;Password=mypassword;Server=localhost;Port=5432;Database=myvaluesdb;Pooling=True;Minimum Pool Size=10;Maximum Pool Size=100;Trust Server Certificate=true;Connection Idle Lifetime=300;keepalive=10;Timeout=60";
        NpgsqlConnection connection = null;

        try
        {
            connection = new NpgsqlConnection(connectionstring);
            connection.Open();
        }
        catch (Exception)
        {
            // try to reconnect
            connection = new NpgsqlConnection(connectionstring);
            connection.Open();
        }

        if (connection.State == ConnectionState.Open)
            Console.WriteLine("connection status = OPEN");
        else
        {
            var exception = new Exception("could not get DB connection");
            throw exception;
        }

        return connection;
    }
}