[vlc-devel] [PATCH 3/3] access/udp: reduce mtu amount on initial packets

[Ilkka Ollakka]

On Tue, Oct 16, 2018 at 03:52:18PM +0200, Francois Cartegnie wrote:
> Le 16/10/2018 à 15:28, Ilkka Ollakka a écrit :
> > 
> > Like mentioned previously, this patch doesn't touch the RTP receiving
> > side of things. If you have case where plain udp access gets highly
> > variable size packets that breaks up, then I'm interested to hear about
> > that.
> > 
> > But if you think I don't need the capture or RTP case is unresolvable by
> > nature without using really high buffers, then we are stuck and we
> > should focus on other things.
> > 
> 
> UDP packet size depends on RTP payload. All your test streams really do
> aggregate RTP packets at byte level and use padding on end ?
> 
> You can clearly see the H264 RTP stream with each NAL < (MTU - headers)
> being in a single packet, so final packet < MTU:
> 
> https://pastebin.com/raw/0TjDjPPU

Thanks for the packet size pastebin.

With those packet sizes, the tinkered patch would set the mtu to be 1378 and
keep it on that. As it has the limits of mtu being over 1500 and then length
being between 1000 and 1500 to reduce the mtu size. It's not perfect, but
should work in this case?

-- 
Ilkka Ollakka