Re: e1000 performance hack for ppc64 (Power4)

[Lincoln Dale <ltd@xxxxxxxxx>]

At 10:41 PM 13/06/2003 -0700, David S. Miller wrote:
>    From: Lincoln Dale <ltd@xxxxxxxxx>
>    Date: Sat, 14 Jun 2003 11:52:53 +1000
>
>    unless i misunderstand the problem, you can certainly pad the TCP
>    options with NOPs ...
>
> You may not mangle packet if it is not your's alone.
>
> And every TCP packet is shared with TCP retransmit
> queue and therefore would need to be copied before
> being mangled.

ok, so lets take this a step further.

can we have the TCP retransmit side take a performance hit if it needs to 
realign buffers?

once again, for a "high performance app" requiring gigabit-type speeds, its 
probably fair to say that this is mostly in the realm of applications on a 
LAN rather than across a WAN or internet.
on a switched LAN, i'd expect TCP retransmissions to be far fewer ...


cheers,

lincoln.