From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Anatoly Sivov" <mm05@mail.ru>
Subject: Re: why does skb->tstamp use getnstimeofday?
Date: Sun, 15 Jan 2012 21:55:06 +0400
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To: "Eric Dumazet" <eric.dumazet@gmail.com>
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Hello Eric,

thanks for your answer.

> monotonic time services were added later.

Yep, I understand.

> It's using this since day 0, so cannot be changed or break applications,
> which expect timeofday, not monotonic.

I missed that field tstamp is used for things other than RTT and can be  
even user-spaced with SO_TIMESTAMP.
However, timekeeper speed up/slow down (due to ntp) can seriously affect  
some congestion avoidance algorithm quality, I guess.
Am I wrong?