[Icecast] Source throttling bug, windows->linux

William K. Volkman
2005-11-14T14:46:50Z

Hi Dan,
	I'm not an expert on icecast however it sounds like the
server is getting stuck somewhere.
On Sun, 2005-11-13 at 23:23, Dan Merillat wrote:
> I'm getting a weird source throttling bug that I just don't know
how
> to track down.
<snip>
>
> So the server goes from a windowsize of 62k to 164 bytes.  Once this
> happens, the XP stack only tries sending one packet every 5 seconds.
>
> What would cause that kind of throttling behavior?  If I restart
> icecast it works for a while, then locks up again.

You don't mention what version of icecast you are using or
what media type you are trying to stream.  That would be
useful information.

What does netstat report as the size of the send/receive queue?
If there are non-zero counts there then the server is not
processing them (perhaps fast enough).

> I've had reports that it happens with windows icecast2 sources as
> well, but I wasn't able to get a tcpdump of it happening for them.
>
> I tried turning off tcp_window_scaling on linux, in case it was
> hitting a bug in XP, but no luck there either.

Seems like a bad idea.

>
> Oddities: I tried setting the server to the lowest priority in linux,
> then running a few CPU hogging programs.  That didn't cause
> a noticible difference.
>
> Ideas where to look?

If your send/receive counts are non-zero you may want to run
a version of the server compiled with debug and then attach
to it with gdb when it gets into this condition.

HTH,
William.