From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH v2 net-next 3/6] tcp: add SACK compression
Date: Thu, 17 May 2018 13:41:21 -0700
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 <20180517174739.192489-4-edumazet@google.com>
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        <toke@toke.dk>, Neal Cardwell <ncardwell@google.com>,
        Yuchung Cheng <ycheng@google.com>,
        Soheil Hassas Yeganeh <soheil@google.com>,
        Eric Dumazet <eric.dumazet@gmail.com>
To: Eric Dumazet <edumazet@google.com>,
        "David S . Miller" <davem@davemloft.net>
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On 05/17/2018 10:47 AM, Eric Dumazet wrote:

> +	/* compress ack timer : 5 % of srtt, but no more than 1 ms */
> +
> +	delay = min_t(unsigned long, NSEC_PER_MSEC,
> +		      tp->rcv_rtt_est.rtt_us * (NSEC_PER_USEC >> 3)/20);
>

Yuchung suggested that we use min(rtt, rcv_rtt), and I totally agree with him.

I will send a v3 with this suggestion.