> > If I corrupt loopback so it fails to transmit a few packets, I can
> > emulate the same kind of TCP stalls that have frequented the kernel.
>
> I'd expect exactly what you describe. TCP cannot cope with loss above
> 1 frame per pipe length without seriois performance loss. Typically thats
> 5-10% loss. Above that it will back off a lot.
>
> Your model is then flawed because the back off doesnt induce lower error
> rates through reduced congestion. You model a continuous 25% loss link
> layer - and that is something that unaided is beyond the capabilities
> of an IP network.
>
> Alan
>
Okay. That's good. This might point to a serious problem with the PPP
link (losing lots of packets), because that's where the bad stalls occur.
I can run serial I/O to serial I/O (regular 'C' programs in Linux) between
two computers with two modems _and_ the phone line with only an occasional
lost character (actually a group of 6), far less than 1/2 percent. Maybe
flow-control isn't working in PPP??
Cheers,
Dick Johnson
***** FILE SYSTEM WAS MODIFIED *****
Penguin : Linux version 2.1.118 on an i586 machine (66.15 BogoMips).
Warning : It's hard to remain at the trailing edge of technology.
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