From mboxrd@z Thu Jan  1 00:00:00 1970
From: Vijay Subramanian <subramanian.vijay@gmail.com>
Subject: Re: tcp_mtu_probe implementation details
Date: Tue, 20 Dec 2011 14:33:01 -0800
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References: <op.v6s5j2i0fzo5me@stalin>
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To: Anatoly Sivov <mm05@mail.ru>
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> The other question is about size_needed variable.
> It is assigned to value probe_size + (tp->reordering + 1) * tp->mss_cache
> And that is not clear for me.
> What is this "(tp->reordering + 1) * tp->mss_cache" addition?
>

I think the idea is that you want enough bytes in the write_queue so
that even if the probe is lost, the sender will get an ack even if
there is reordering in the network. Without sufficient bytes, the
probe will not be sent. This is what I make of the code but I could be
wrong.

Regards,
Vijay