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SubjectPoor PPP performance and txqueuelen
From the archives:

>> If not, wouldn't it be better to keep txquueuelen high and
>> just grin and bear the latency for interactive use?
> No you want it smaller, this makes packet loss feedback happen much
> more quickly, and thus TCP's heuristics respond to the situation faster.
> David S. Miller

That does not work well here. And it seems to contradict the ethernet
default of 100 for txqueuelen.

I have a 2.2.14aa1 box routing between ethernet and dialup PPP
interfaces. With the default PPP txqueuelen of 10, or if I set the
PPP txqueuelen to a smaller value such as 3, I get dropped packets and
poor FTP performance thru the Linux router.

But if I set Linux PPP txqueuelen to 30 or more, there are no dropped
packets and FTP performance thru the Linux router is perfect.

In ppp.c, the default value for receive queue length is 32. In my
local ppp.c, I've also changed the default transmit queue length to
32, and it works much better now.

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