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DateWed, 02 Mar 2005 09:37:56 +0000
FromBaruch Even <>
SubjectRe: Network speed Linux-2.6.10
Paul Dickson wrote:
> On Wed, 02 Mar 2005 01:02:50 +0000, Baruch Even wrote:
> 
>>>Might this be related to the broken BicTCP implementations in the 2.6.6+
>>>kernels?  A fix was added around 2.6.11-rc3 or 4.
>>
>>Unlikely, the problem with BIC would have shown itself only at high 
>>speeds over long latency links, not over a lan connection.
> 
> I only mentioned the possibility because I saw the same profile given by
> the PDF (the link was mentioned in the patch) while downloading gnoppix
> via my cable modem.  The oscillations of speed varied from 40K to 500+K.
> The average ended up around 270K.  (I was using wget for the download).

If it is indeed BIC than we have a bug where it doesn't shut itself off 
for low latencies. Since we don't test this case extensively here (we 
work to improve high-speed and just make sure we don't ruin slower 
speeds) I can't say it's impossible, try turning BIC off and see if it 
helps.

Due to the scenario that the OP gave it is more likely something to do 
with auto-detection somewhere along the way or a driver bug. It is also 
possible that I'm mistaken and it is BIC, never hurts to check.

Baruch
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