Ethernet Performance (Collisions)

Michael Vallaly mvallaly@purdue.edu
Thu Jan 21 15:44:40 1999


Im kinda new to this so please bare with me.. :)

I am wondering why my performance is lacking while using the Intel
EtherExpress Pro 100+.
I feel its due to the collisions on my network, but I can't seem to find
what is causing them. 
I am running IP-Masq on my linux box to allow my windows machine to connect
to the internet.
I have (2) EEpro100+ cards on (2) diffrenet networks physicaly located in my
linux box.
I get massive collisions on both networks no matter how I set the card or
what driver I use. 
I have reached a maximum 2000kb/s doing local FTP transfers between my Linux
Box and my Windows Box. (100mbit)
Once the speed reaches the 2000kb/s point the collision light on the hub
begins to flash about once ever 3 seconds, each time slowing the transfer to
about 1000kb/s. 
The card connected to the Internet Gateway hub also recives a lot of collisions.
I have tired every single combination of Half-Duplex / Full Duplex. 
Full Duplex eliminates the collisions all together on both cards but the
performance does not increase and they frame and carrier numbers continue to
climb.
I have also run the both the Windows and Linux cards at 10mbit.. The
performance does not seem to change.. 
I have tried forcing the cards to specific speeds and duplex's (and have
tried a crossover cable instead of the 100mbit hub) with no change in
performance
Is this problem a hardware, software or a bit of both?
Should a two computer network suffer from massive collisions? 
Should I come to expect massive amounts of collisions on 100mbit cards?
Would Compiling the driver in the kernel help?
Could someone fill me in on what the Frame and Carrier numbers are/mean in
ifconfig?
Hopefully someone can figure out what im doing wrong. :)


conf.modules specs:

alias eth0 eepro100
alias net-pf-5 off

Ifconfig Specs: Eth0 = Switched 10mbit Internet Gateway  Eth1 = Local
100mbit network.

lo        Link encap:Local Loopback
          inet addr:127.0.0.1  Bcast:127.255.255.255  Mask:255.0.0.0
          UP BROADCAST LOOPBACK RUNNING  MTU:3584  Metric:1
          RX packets:354 errors:0 dropped:0 overruns:0 frame:0
          TX packets:354 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0

eth0      Link encap:Ethernet  HWaddr 00:90:27:32:29:1D
          inet addr:XXX.XXX.XXX.XXX  Bcast: XXX.XXX.XXX.XXX  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:317231 errors:0 dropped:0 overruns:0 frame:39
          TX packets:294442 errors:0 dropped:0 overruns:0 carrier:32
          collisions:82883
          Interrupt:10 Base address:0xef40

eth1      Link encap:Ethernet  HWaddr 00:90:27:30:B7:6D
          inet addr: XXX.XXX.XXX.XXX  Bcast: XXX.XXX.XXX.XXX  Mask:255.255.255.0
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:134732 errors:0 dropped:0 overruns:0 frame:5
          TX packets:25445 errors:0 dropped:0 overruns:0 carrier:0
          collisions:221
          Interrupt:9 Base address:0xef20

Network Specs:
All Cat5 cable..
One (1) Linksys EtherFast 100baseTX 4 port Hub.
One (1) 10mbit (Switched) Connection to Internet Gateway.

Linux Box Specs:
Supermicro P6DBE Dual PII Motherboard running with one (1) 350mhz PII @
100mhz bus
(have disabled PnP OS support, and have tried setting PCI config to Auto and
Manual)
Two (2) Intel EtherExpress Pro 100+ ethernet cards
Generic S3 Video Card
4.6 gig IDE
6x IDE cdrom 
Running RedHat 5.2 (all patches)
Running eepro100.o v1.05 (upgraded from v.99B)

Windows Box Specs:
PII 400mhz
3com 3c905b/TX 10/100 Ethernet card.


Network Layout:
_____                                                                 _______
|         |  100mbit TX   ________  100mbit TX    |             |    10mbit 
| Win  |--------------- | Linksys  |----------------| Linux
|---------------->
|  98   |                        | 100mbit |                        |    Box
|     (to Internet)
-------                        | TX hub  |                        |
|       Gateway
                                  -----------                        ----------


Please feel free to mail me if you need to.. thanks again for your time..

-Mike