netdev - Re: [RFC 1/3] tcp: randomize tcp timestamp offsets for each connection

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Message-ID: <20160825144958.GA5248@breakpoint.cc>
Date:   Thu, 25 Aug 2016 16:49:58 +0200
From:   Florian Westphal <fw@...len.de>
To:     Eric Dumazet <eric.dumazet@...il.com>
Cc:     Florian Westphal <fw@...len.de>, netdev@...r.kernel.org
Subject: Re: [RFC 1/3] tcp: randomize tcp timestamp offsets for each
 connection

Eric Dumazet <eric.dumazet@...il.com> wrote:
> Here at Google we have been using usec resolution in TCP timestamps for
> a while for all our DC traffic, and we have to upstream this at some
> point.
> 
> It would be nice if the randomization was optional, because having usec
> timestamps with a common base (ie no per flow random base) helps a lot
> to understand the host delays at transmit time, and receive time.

Would it help to make it per-host instead of per-flow?

> I will review your patch more in depth today, thanks.

Great, thanks a lot!