Consult everybody:
Recently in learning, POSTGRE on the c #, found that connect to the database for the first time is slow, about a second, then quickly,
String the connectionString="Server=localhost; Port=5432; The Username=postgres; Password=12345; The Database=ft; ";
Conn1=new NpgsqlConnection (the connectionString);
Conn1. The Open ();
,,,,,,,,,,
Conn1. Close ();

Everyone is like this?
What reason is this?
Also, download the PG 13 version, c # can't even on (he, of course, also under the Npgsql), later in the PG 10 version, even,
You have met? Can you explain?