Re: [PATCH v2] tcp: splice as many packets as possible at once

[David Miller]

From: David Miller <davem@xxxxxxxxxxxxx>
Date: Mon, 26 Jan 2009 22:10:56 -0800 (PST)

> Even for drivers like NIU and myri10ge that do this, they only
> use heuristics or some fixed minimum to decide how much to
> move to the linear area.
> 
> Result?  Some data payload bits end up there because it overshoots.
 ...
> I did test this with the NIU driver at one point, and it did not
> change TCP latency nor throughput at all even at 10g speeds.

As a followup, it turns out that NIU right now does this properly.

It only pulls a maximum of ETH_HLEN into the linear area before giving
the SKB to netif_receive_skb().
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