Re: 2.4 tcp very slow under certain circumstances (Re: netdev issues (3c905B))

[Ookhoi <ookhoi@dds.nl>]

Hi Jordan,

> >  > We have exactly the same problem but in our case it depends on the
> >  > following three conditions: 1, kernel 2.4 (2.2 is fine), 2, windows ip
> >  > header compression turned on, 3, a free internet access provider in
> >  > Holland called 'Wish' (which seemes to stand for 'I Wish I had a faster
> >  > connection').
> >  > If we remove one of the three conditions, the connection is oke. It is
> >  > only tcp which is affected.
> >  > A packet on its way from linux server to windows client seems to get
> >  > dropped once and retransmitted. This makes the connection _very_ slow.
> > 
> > :-( I hate these buggy systems.
> > 
> > Does this patch below fix the performance problem and are the windows
> > clients win2000 or win95?
> 
> I wanted to see if this would fix the problem I was seeing with Win9x
> users on PPP w/ compression dialing up to Earthlink in the bay area
> (there are others, but it's the only one I can reproduce).
> 
> I compiled 2.4.1 with this change and for some odd reason, the kernel
> started dropping packets and became unusable (couldn't ssh in) after
> around 4050 connections were opened. I tested it also with 2.4.1-ac20
> and had the same problem right around 4050 connections.
> 
> This is on a VA Linux box with dual eepro100's (one used) connected to a
> Cisco 6509.

I patched two computers, 2.4.1-ac20. One of them is a fairly loaded
webserver. Both have an uptime of 15.15 and 16.30 hours, and are fine.
Didn't test with that much connections though.

	Ookhoi