From mboxrd@z Thu Jan  1 00:00:00 1970
From: "David S. Miller" <davem@davemloft.net>
Subject: Re: [RFC] TCP congestion schedulers
Date: Mon, 21 Mar 2005 13:51:54 -0800
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To: John Heffner <jheffner@psc.edu>
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On Mon, 21 Mar 2005 16:25:56 -0500 (EST)
John Heffner <jheffner@psc.edu> wrote:

> Would you really expect a single extra indirect call per ack to have a
> significant performance impact?  This is surprising to me.  Where does the
> cost come from?  Replacing instruction cache lines?

Maybe not for ACK processing (that's very thick already) but
perhaps for a lighter fast path definitely so.