From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH v3 net-next] tcp: TSO packets automatic sizing
Date: Thu, 29 Aug 2013 16:35:28 -0400 (EDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Thu, 29 Aug 2013 13:26:17 -0700

> Typical bufferbloat at the end of transfert :
> 
> [ 4547.051521] TCP: sk ffff88085825d180 cwnd 327 packets 3 rate 7575936000/srtt 1581
> [ 4547.052722] TCP: tcp_ack_update_rtt sk ffff88085825d180 seq_rtt 198 sack_rtt 4294967295
> [ 4547.052726] TCP: tcp_rtt_estimator sk ffff88085825d180 mrtt 198 srtt 1581
> [ 4547.052729] TCP: sk ffff88085825d180 cwnd 327 packets 1 rate 7575936000/srtt 1582
> [ 4547.053315] TCP: tcp_ack_update_rtt sk ffff88085825d180 seq_rtt 198 sack_rtt 4294967295
> [ 4547.053318] TCP: tcp_rtt_estimator sk ffff88085825d180 mrtt 198 srtt 1582
> [ 4547.053321] TCP: sk ffff88085825d180 cwnd 327 packets 0 rate 7575936000/srtt 1583
> 
> Maybe we could instead store a value corrected by the sk_pacing_rate
> 
> rate = (big_cwin * mss) / big_srtt
> 
> stored_rtt = rate / (big_cwin * mss)

No objections from me.