Re: [tcpm] A question about PTO/RTO rescheduling in RACK draft

hiren panchasara <hiren@strugglingcoder.info> Wed, 17 April 2019 21:15 UTC

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Date: Wed, 17 Apr 2019 14:15:21 -0700
From: hiren panchasara <hiren@strugglingcoder.info>
To: Neal Cardwell <ncardwell@google.com>
Cc: Matt Olson <maolson@microsoft.com>, draft-cheng-tcpm-rack@ietf.org, "tcpm@ietf.org" <tcpm@ietf.org>, Yi Huang <huanyi=40microsoft.com@dmarc.ietf.org>, Yuchung Cheng <ycheng@google.com>, Nandita Dukkipati <nanditad@google.com>, Priyaranjan Jha <priyarjha@google.com>
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Subject: Re: [tcpm] A question about PTO/RTO rescheduling in RACK draft
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On 04/17/19 at 04:29P, Neal Cardwell wrote:
> Hi Yi and Hiren,
> 
> Thank you for raising this question and the continued discussion.

Thanks for a quick response as always. :)

[skip]
> We will need to update the draft to make these aspects more clear. Thank
> you for raising this!

I'll keep this to the point I thought got missed.

https://tools.ietf.org/rfcdiff?url2=draft-ietf-tcpm-rack-04.txt

Is where we can see `Scheduling a loss probe` getting changed.
Specifically, following condition has been removed from -04:

   3.  The connection is either limited by congestion window (the data
       in flight matches or exceeds the cwnd) or application-limited
       (there is no unsent data that the receiver window allows to be
       sent).

And afaict, Linux code still has this condition in. If you can provide
some rationale behind this change, it'd be great.

Thanks a ton,
Hiren