public static void TrimDnsCache()
{
var countBeforeTrim = Dns.Count;
var tenth = countBeforeTrim / 10;
//remove the ones with expired dates first
foreach (var item in Dns.Where(x => x.Value.ExpireDate < DateTime.Now).ToList())
{
Dns.Remove(item.Key);
}
if (Dns.Count != countBeforeTrim)
{
Console.WriteLine($"Removed {countBeforeTrim - Dns.Count} expired dns");
}
//if cache is still quite full, then trim a little more
var rest = tenth - (countBeforeTrim - Dns.Count);
if (rest < 0)
{
return;
}
foreach (var item in Dns.Take(rest).ToList())
{
Dns.Remove(item.Key);
}
Console.WriteLine("Trimming DNS to 9 tenths");
}
