Remote Window Size

rapier rapier at
Thu May 5 02:06:39 AEST 2022

On 5/4/22 2:40 AM, Damien Miller wrote:
> On Tue, 3 May 2022, rapier wrote:
> If you can similarly instrument the peer, then it might shed some light on
> it. Some possibilities:
> 1) heaps of data in flight (e.g. bufferbloat on intervening routers)
> 2) a peer with a full output buffer for the channel, e.g. if it was
>     writing to a disk that is slower than the network. This will cause
>     backpressure via c->local_consumed (see end of channel_handle_wfd())
> 3) some stupid bug where we miss a case to update c->channel_handle_wfd
>     or do the math wrong in channel_check_window()
> hope this helps!

It certainly does. I'm trying to narrow down the failure conditions but 
it seems that it may be related to using IPv6 when there is a high 
enough RTT to cause a lot of inflight data. As I get more information 
I'll let you know what I find out. It's probably in my code but I wanted 
to get a better grip on whats happening with these values.

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