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Subject: Re: [RFC PATCH RESEND] tcp: avoid F-RTO if SACK and timestamps are
 disabled
To:     Yuchung Cheng <ycheng@google.com>,
        Michal Kubecek <mkubecek@suse.cz>
Cc:     netdev <netdev@vger.kernel.org>,
        Eric Dumazet <edumazet@google.com>,
        Ilpo Jarvinen <ilpo.jarvinen@helsinki.fi>,
        linux-kernel@vger.kernel.org
References: <20180613164802.99B89A09E2@unicorn.suse.cz>
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 <CAK6E8=eCOLU9AX0+bSrOg_UYBm1mFxrGT=ybksba9B0OUfp7jg@mail.gmail.com>
From:   Eric Dumazet <eric.dumazet@gmail.com>
Message-ID: <4cc1a197-abc0-8785-fb79-79e99bc25980@gmail.com>
Date:   Wed, 13 Jun 2018 10:48:05 -0700
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On 06/13/2018 10:32 AM, Yuchung Cheng wrote:
> On Wed, Jun 13, 2018 at 9:55 AM, Michal Kubecek <mkubecek@suse.cz> wrote:
>>
>> When F-RTO algorithm (RFC 5682) is used on connection without both SACK and
>> timestamps (either because of (mis)configuration or because the other
>> endpoint does not advertise them), specific pattern loss can make RTO grow
>> exponentially until the sender is only able to send one packet per two
>> minutes (TCP_RTO_MAX).

>> Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
> Acked-by: Yuchung Cheng <ycheng@google.com>
> 
> Thanks for the patch (and packedrill test)! 

Yes, thanks a lot Michal.

Signed-off-by: Eric Dumazet <edumazet@google.com>