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Message-ID: <1518988012.55655.16.camel@gmail.com>
Subject: Re: TCP and BBR: reproducibly low cwnd and bandwidth
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Oleksandr Natalenko <oleksandr@natalenko.name>,
        Eric Dumazet <edumazet@google.com>
Cc: Neal Cardwell <ncardwell@google.com>,
        "David S. Miller" <davem@davemloft.net>,
        Netdev <netdev@vger.kernel.org>,
        Yuchung Cheng <ycheng@google.com>,
        Soheil Hassas Yeganeh <soheil@google.com>,
        Jerry Chu <hkchu@google.com>, Dave Taht <dave.taht@gmail.com>
Date: Sun, 18 Feb 2018 13:06:52 -0800
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On Sun, 2018-02-18 at 13:04 -0800, Eric Dumazet wrote:
> 
> Can you please test the following patch ?
> 
> Note that some cleanups can be done later in TCP stack, removing lots
> of legacy stuff.
> 
> Also TCP internal-pacing could benefit from something similar to this
> fq patch eventually, although there is no hurry.
> https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git/commit/?id=fefa569a9d4bc4b7758c0fddd75bb0382c95da77  
> 
> Of course, you have to consider why SG was disabled on your device,
> this looks very pessimistic.
> 
> Thanks !
> 
>  include/net/sock.h  |    1 +
>  net/core/sock.c     |    2 +-
>  net/ipv4/tcp_ipv4.c |    1 +
>  net/ipv6/tcp_ipv6.c |    1 +
>  4 files changed, 4 insertions(+), 1 deletion(-)

Also note that the patch only deals with active connections.

My official patch will also take care of passive ones of course.