FXP driver....

Daniel Gonzalez spammesilly at gmail.com
Fri Aug 19 18:11:59 GMT 2005

> Hi,
> I've build a new P4 box (1.8Ghz, 512MB mem) based upon a ASUS P4B533VM
> motherboard. This board has an Intel 845G chipset and onboard 10/100
> mbit/s LAN (fxp driver).
> When connected directly to a gateway (in my case an Extreme BD10k) I
> observe the following behaviour: a ping to the gateway starts around
> 1ms and slowly increases in steps of .1 or .2ms to around 10ms. Then
> it suddenly drops back to 1ms and the process starts all over again.
> I've tried a different NIC (3com, xl driver), new cabling, new
> switchport and all gives me the same result. My other labbox (a AMD
> 2000 XP+ with 3com PCI nic) connected to the same router is showing
> normal latency. This gives me the feeling it's some sort of timing
> issue on the P4's motherboard itself.
> Has anyone seen this before? I've searched the archives and found
> little on this topic. Any tips/hints where I can seach for further
> clues?
> Thanks,
> Arjan

I haven't used the fxp driver in a while but you can check out the man page 
for the driver (man 4 fxp) and it mentions that you can disable autoselect 
for media type and speed. I remember reading in an article (I can't locate 
the URL) that the autonegotiation between the NIC and switch/router can be a 
bottleneck. That would be the easiset thing to check/eliminate. Hope that 
Dan Gonzalez
spammesilly at gmail.com
IM: signulth

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