you may be interested in trying. I can't try them myself right now due
to an incompatible router, but I thought I should post these anyway and
see if other people can use them. These are all player file tweaks that
I think would help from a bandwidth standpoint.
In the [ Graphic Options ] section there is the following line:
Max Visible Vehicles="21"
I don't know whether this affects network traffic or is just a client
side setting, but in Papy games the number of visible vehicles is
restricted in order to reduce bandwidth. I would suggest reducing this
to 10 or less and seeing if it makes a difference.
Under [ Multiplayer Options ] there is both a "Net Data Rate" and a "Net
Data Rate Max" setting. I believe the first is set when you pick your
connection type, but I am not sure about the second. For broadband
hosts the key to getting a smooth game is limiting the client rates, and
this second variable appears to be the way to do it. So if it isn't set
by connection type, then anyone running a server should explicitly set
it. According to some of the message boards I have looked at, the
optimum is 12 (updates per second?) which amounts to effectively modem
bandwidth. If it isn't clear why this should be so, please refer to my
article http://www.racesimcentral.net/
This article is directed at setting up FPS games, but it explains some
of the reasons why broadband is not that good for hosting and why you
have to be very careful both about data rate limits and number of
players when running a broadband server.
Again under [ Multiplayer Options ] there is the following line:
Net Flush Threshold="472" // threshold for auto-accumulation flush while
building data chunks (default is standard MTU of 536, minus 64 bytes
room for layer headers: 472)
This line and the accompanying comments is, I am fairly certain, wrong.
The standard MTU for modem users is 576, not 536. And if you are on bro
adband your MTU is most likely 1500. If I am right about this then
modem users should set the Net Flush Threshold to 512 and broadband
users should set it to 1436. This would be true regardless of whether
you are a client or server, since it is only really affecting the packet
size sent from you to your ISP. Once out on the net the packets will be
fragmented into 576 byte chunks anyway, but using the largest MTU that
your ISP supports will increase your effective data rate by reducing the
percentage of your alloted upstream bandwidth that is wasted on
communications overhead. I expect that this would be especially
important for the broadband host who needs to make as efficient use as
possible out of this limited upstream bandwidth.
Again under [ Multiplayer Options ] :
Net Lazy Flush="0" // an explicit flush will not be called after the
server re-transmits incoming data, providing less bandwidth consumption
by reducing header sizes, but will increase latency
Has anyone experimented with that setting? Sounds like it is worth
trying it set to 1 to see what the effect is.
Max MP Players="16"
Here it is necessary to be realistic about your available bandwidth. If
you have a typical broadband setup your upstream rate is probably
128kbps. If you are limiting the clients to 56kbps that means you can
only have 2 clients (128/56 = 2.3). If you have 256kbps upstream you
can serve 4 players, which means including you the Max MP Players should
be set to 5. You can try squeezing it to 6, but it could get dicey.
This is reality, FPS players have been dealing with it for years, but
for some reason racers still don't seem to understand this. Broadband
just is not acceptable for serving large number of players, for that you
need a dedicated server on a T1 or better. That's life. On a T1 for
example you could support 1.5mbps/56kbps = 26 clients (rounded off), or
alternately you could reduce the number of players and increase the data
rate.
Lastly, although this has been published elsewhere I thought I would
repeat it:
Closed MP Qualify Sessions="1" // if true, the session will be closed
during qualify, so as to not disturb the participants
Always set to 1 to prevent warping during qualifying.
Hope that helps. One of these days I'm going to get off my ass and get
a decent router, and then maybe I will be able to join you guys. Until
then, good luck to you!