suffering from poor network performance...

[Alex (ander Sendzimir)]

First, I know very little about networking, especially performance 
turning. I would really like to learn more but don't know where/how to 
start effectively.

I have a small home network with a PowerBook G4 and FBSD 4.9-STABLE 
connected through a Netgear DS108 hub (10/100). The FBSD box is a dual 
Xeon 500MHz with Intel Etherexpress 100/Pro (MS440GX motherboard). If 
for some reason it makes a difference, there is an RT311 router 
connected to the hub as well. This is the router through which these 
machines see the internet. There are other machines connected to the 
network. However, they are currently turned off.

In my limited knowledge I'm using ping from each host to the other. 
 From the FBSD system to the G4 system, I'm getting nearly 60% packet 
loss and about 20% in the other direction. I'm ready to use tcpdump but 
I'm not sure how I would. How can/should I go about improving network 
performance?

Thanks for the help.
Alex


ifconfig on the PowerBook G4 gives:

lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384
         inet6 ::1 prefixlen 128
         inet6 fe80::1%lo0 prefixlen 64 scopeid 0x1
         inet 127.0.0.1 netmask 0xff000000
gif0: flags=8010<POINTOPOINT,MULTICAST> mtu 1280
stf0: flags=0<> mtu 1280
en0: flags=8863<UP,BROADCAST,SMART,RUNNING,SIMPLEX,MULTICAST> mtu 1500
         inet6 fe80::20a:95ff:fe77:5140%en0 prefixlen 64 scopeid 0x4
         inet 192.168.0.3 netmask 0xffffff00 broadcast 192.168.0.255
         ether 00:0a:95:77:51:40
         media: autoselect (100baseTX <half-duplex>) status: active
         supported media: none autoselect 10baseT/UTP <half-duplex> 
10baseT/UTP <full-duplex> 10baseT/UTP <full-duplex,hw-loopback> 
100baseTX <half-duplex> 100baseTX <full-duplex> 100baseTX 
<full-duplex,hw-loopback> 1000baseTX <full-duplex> 1000baseTX 
<full-duplex,hw-loopback> 1000baseTX <full-duplex,flow-control> 
1000baseTX <full-duplex,flow-control,hw-loopback>

ifconfig on the dual Xeon gives:

fxp0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
         inet 192.168.0.2 netmask 0xffffff00 broadcast 192.168.0.255
         ether 00:90:27:3e:b2:66
         media: Ethernet autoselect (100baseTX)
         status: active
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> mtu 16384
         inet 127.0.0.1 netmask 0xff000000

I know both interfaces are configured for half-duplex. Perhaps 
full-duplex would help? How to enable under Mac OS X 10.2? Otherwise, I 
know how to do it under FBSD in /etc/rc.conf.

When I ping from one machine to the other I get nearly 60% packet loss 
from Xeon to G4 system and about 20% packet loss from G4 to Xeon. I'm 
issuing the following commands to get this output (with some <snipping> 
for the list):

 > ping -f -c {1000,2000,4000,8000} name-of-host

Xeon -> G4:

1.
PING hardy (192.168.0.3): 56 data bytes
1000 packets transmitted, 500 packets received, 50% packet loss
round-trip min/avg/max/stddev = 0.795/0.859/1.081/0.021 ms

2.
PING hardy (192.168.0.3): 56 data bytes
2000 packets transmitted, 900 packets received, 55% packet loss
round-trip min/avg/max/stddev = 0.501/0.858/1.111/0.022 ms

3.
PING hardy (192.168.0.3): 56 data bytes
4000 packets transmitted, 1600 packets received, 60% packet loss
round-trip min/avg/max/stddev = 0.784/0.859/1.042/0.017 ms

4.
PING hardy (192.168.0.3): 56 data bytes
8000 packets transmitted, 3100 packets received, 61% packet loss
round-trip min/avg/max/stddev = 0.612/0.858/0.996/0.017 ms


G4 -> Xeon:

1.
PING newton (192.168.0.2): 56 data bytes
1240 packets transmitted, 1000 packets received, 19% packet loss
round-trip min/avg/max = 0.251/1.048/16.451 ms

2.
PING newton (192.168.0.2): 56 data bytes
2539 packets transmitted, 2000 packets received, 21% packet loss
round-trip min/avg/max = 0.171/1.057/12.42 ms

3.
PING newton (192.168.0.2): 56 data bytes
5118 packets transmitted, 4000 packets received, 21% packet loss
round-trip min/avg/max = 0.205/1.088/13.318 ms

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Alexander Sendzimir                             802 863 5502
  MacTutor of Vermont               info @ mactutor . vt . us
   Colchester, VT 05446                 ( not yet active )