bad TCP performance

[Russell Nelson]

David Miller writes:
 > 
 > If you are getting frame errors, it is a problem with the network card
 > driver.  Such errors have nothing to do with Linux's TCP, frame errors
 > happen and the packet is tossed before the Linux networking code can
 > even see the packet.

And TCP interprets an unreliable connection as congestion, and
exponentially backs off.  If you have a router which drops every other
packet (I saw that once), or if you've got a 3c501 which didn't have
enough buffer space for two back-to-back packets (and you don't have
your window set to your mss), then TCP will back off on *every*
packet.  And login takes enough packets (every character gets echoed,
which takes a round-trip) that you can barely login before the 60
second timeout.

-- 
-russ nelson <rn-sig@crynwr.com>  http://crynwr.com/~nelson
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