From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: Network performance degradation from 2.6.11.12 to 2.6.16.20
Date: Mon, 18 Sep 2006 14:22:47 -0700 (PDT)
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From: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Date: Tue, 19 Sep 2006 01:03:21 +0400

> 1. It even does not disable possibility to record timestamp inside
>    driver, which Alan was afraid of. The sequence is:
> 
> 	if (!skb->tstamp.off_sec)
>                 net_timestamp(skb);
> 
> 2. Maybe, netif_rx() should continue to get timestamp in netif_rx().
> 
> 3. NAPI already introduced almost the same inaccuracy. And it is really
>    silly to waste time getting timestamp in netif_receive_skb() a few
>    moments before the packet is delivered to a socket.
> 
> 4. ...but clock source, which takes one of top lines in profiles
>    must be repaired yet. :-)

Ok, ok, but don't we have queueing disciplines that need the timestamp
even on ingress?