Does anyone have an information or experience with the use of Universal
Serial Bus modems in the online *** environment? It would seem that
USB-based modems would be an ideal solution for racing GPL online,
because they eliminate the serial port and its requirement for frequent
interrupts of the CPU.
When racing GPL online, the CPU is very busy. When the CPU becomes
saturated, the serial port limits the bandwidth available, interrupting
data transmission between client and server. The results are clock
smashes (screen flashes followed by giant warps), and, all too
frequently, disconnects.
Cable modem hosts have become quite popular on VROC, and they work very
well. A big part of the advantage of cable modems is that they do not
use the serial port; instead, they connect to the PC through an Ethernet
adapter, which has much higher bandwidth and places much less load on
the CPU than the serial port.
Also, 128 kb ISDN connections through an ISDN router (which also uses an
Ethernet adapter) seem to be able to host as many as 10 to 12 players
reliably in GPL. By contrast, a 128 kb ISDN modem (connected through
the serial port) is limited to perhaps 6 to 8 players. Without careful
tuning of modem and DUN settings, and the use of a core.ini which
reduces GPL's bandwidth, the limit is more like 5.
All of this information and experience suggests that a USB modem would
be a far superior solution for GPL than a normal serial port modem.
However, I've been searching around online for ***-related
information on USB modems, and have not been able to find anything.
Does anyone have any relevant information, or can you point me to Web
sites which do?
Incidentally, the MultiTech USB V.90 modem is available for a little
over $100 in the US, via mail order. If I can get some information
confirming USB modems as a significant improvement over serial port
modems for online ***, I'll place an order right away.
Alison
Remove the spam blocker NOSPAM to email me.
http://www.simracing.com/~alison [address restored]
do internal modems have the same issues? why not just use one of them? I
read somewhere that internal modems gave a 20-30 ms better ping I think.
What about PCI modems. Are they much better than ISA slot modems?
Lutrell
>do internal modems have the same issues? why not just use one of them? I
>read somewhere that internal modems gave a 20-30 ms better ping I think.
I'm not sure about modems specifically, but after removing ALL
ISA cards from my 'puter and running PCI + AGP only (I have a
cable modem with PCI ethernet) the overall performance of my
system has improved visibly (as opposed to a few more FPS, the
system really is noticably faster in games and apps)
I suspect the presence of ISA cards (used or not) is enough to slow
the system down as it talks to the much slower 16 (or even 8) bit cards
at the much lower ISA bus speed. Removing all my ISA cards felt like
a CPU upgrade! (sorta :-) PCI based game-port makes for better
wheel control as well (less jittery).
My spec : p2-300 / BX / 8mb Voodoo2 / i740AGP / ESS Solo1 PCI
sound and Realtek PCI ethernet to motorola ***-surfer cable modem.
It stands to reason that USB modems should reduce load on the CPU
compared to standard UART based serial ports which hog bandwidth.
I'm*** out for the USB based wheels which I hope will take more
load off the CPU.
Jet (finally into 1:06's at the Glen :-)
Quoted text (7 lines)
>What about PCI modems. Are they much better than ISA slot modems? >Lutrell >>do internal modems have the same issues? why not just use one of them? I >>read somewhere that internal modems gave a 20-30 ms better ping I think.No info on USB modems but I've solved some severe problems with GPL online
that point directly to the type and quality of modem used.
I could not get either of two 56K PCI modems to connect to any host I could
find but worked fine otherwise, while a 33.6K ISA had no problem connecting
to any host but with sever problems in play with warping, flashes, clock
smashes, etc.
Installed a 56K ISA USR modem last night. Problems are gone! Had the best
game play ever. Couldn't catch Alison at Spa, though. :-)
Observations:
Latency is more important than speed. The two 56K PCIs consistantly showed
twice the ping times (.500ms-.600ms) of the 33.6K ISA and the new 56K ISA
(.200ms-.300ms).
So called 'winmodems' are inferior to non-winmodems because their
controlerless design has no hardware serial port and uses software support
through Windows which will burden the CPU, a real problem in GPL.
Game play on a good host with cable modem is very good now.
If your having problems with online play, get a good non-controlerless
modem.
Marty
Quoted text (46 lines)
> Does anyone have an information or experience with the use of Universal > Serial Bus modems in the online *** environment? It would seem that > USB-based modems would be an ideal solution for racing GPL online, > because they eliminate the serial port and its requirement for frequent > interrupts of the CPU. > When racing GPL online, the CPU is very busy. When the CPU becomes > saturated, the serial port limits the bandwidth available, interrupting > data transmission between client and server. The results are clock > smashes (screen flashes followed by giant warps), and, all too > frequently, disconnects. > Cable modem hosts have become quite popular on VROC, and they work very > well. A big part of the advantage of cable modems is that they do not > use the serial port; instead, they connect to the PC through an Ethernet > adapter, which has much higher bandwidth and places much less load on > the CPU than the serial port. > Also, 128 kb ISDN connections through an ISDN router (which also uses an > Ethernet adapter) seem to be able to host as many as 10 to 12 players > reliably in GPL. By contrast, a 128 kb ISDN modem (connected through > the serial port) is limited to perhaps 6 to 8 players. Without careful > tuning of modem and DUN settings, and the use of a core.ini which > reduces GPL's bandwidth, the limit is more like 5. > All of this information and experience suggests that a USB modem would > be a far superior solution for GPL than a normal serial port modem. > However, I've been searching around online for ***-related > information on USB modems, and have not been able to find anything. > Does anyone have any relevant information, or can you point me to Web > sites which do? > Incidentally, the MultiTech USB V.90 modem is available for a little > over $100 in the US, via mail order. If I can get some information > confirming USB modems as a significant improvement over serial port > modems for online ***, I'll place an order right away. > Alison > Remove the spam blocker NOSPAM to email me. > http://www.simracing.com/~alison [address restored]Internal modems have the same problem as externals. They're both serial
devices talking through a serial port.
Trips
> do internal modems have the same issues? why not just use one of them? I
> read somewhere that internal modems gave a 20-30 ms better ping I think.
The bottleneck for modems is the serial port, not the bus.
Trips
Quoted text (7 lines)
> What about PCI modems. Are they much better than ISA slot modems? > Lutrell > >do internal modems have the same issues? why not just use one of them? I > >read somewhere that internal modems gave a 20-30 ms better ping I think.<grin> Actually, due to serious clock smashing, GPL thought I did a 12
second lap at Spa that night. In reality, I finished behind Marty and
three or four others in that race.
The good news is that I have also solved some severe problems with GPL
online that plagued my new P2-350 since I built it. These problems
included the dreaded clock smashing (which results in giant warps), as
well as random disconnects.
The problem appears to have been the drivers for a SupraExpress 336e Sp.
Some time ago, I switched to an external Motorola 56 kb ModemSURFR, but
left the SupraExpress drivers in place so I could use the Supra when I
wanted both of my computers online at the same time (for testing new
VROC features, for example).
The Supra works fine (more or less) on my older K6-225, but it seems to
be poison on the P2. Once I deleted the SupraExpress from Windows on
the P2, the clock smashing problems I'd been having on the P2 vanished,
along with other DUN irregularities which had me almost tearing my hair
out since I built that machine.
This is not meant to be a criticism of Supra modems, but only a
statement that my particular computer, for some unknown reason, has a
problem with the Supra driver.
I totally agree with Marty on his observations and advice. GPL needs
serious CPU power, and anything that burdens the CPU, such as Winmodems,
are to be scrupulously avoided.
Alison
Remove the spam blocker NOSPAM to email me.
http://www.nh.ultranet.com/~alison
<...>
And I still have your 12.xx second lap on my Spa record indicator!
Too lazy to figure out how to clear it...
But thanks for clearing the race up- I was a bit confused about order
at the end of that race. It was a good race.
