[Live-devel] GroupsockHelper.cpp and weird problems with long startuptimes for applications

[Morgan Tørvolt]

Hi all

I am having some weird problems at the moment. I am running a server
and a laptop with the exact same kernel and software (obviously
different hardware), and having some strange problems with that.

On my laptop, starting the testOnDemandRTSPServer takes no time at
all. On my server, the application uses a few seconds to start.
Running valgrind and killing the process while in this "waiting state"
at the beginning tells me:


==26912== Process terminating with default action of signal 2 (SIGINT)
==26912==    at 0x568D053: select (in /lib/libc-2.6.1.so)
==26912==    by 0x448116: readSocket(UsageEnvironment&, int, unsigned
char*, unsigned, sockaddr_in&, timeval*) (in
/home/mt/live/testProgs/testOnDemandRTSPServer)
==26912==    by 0x44868B:
ourSourceAddressForMulticast(UsageEnvironment&) (in
/home/mt/live/testProgs/testOnDemandRTSPServer)
==26912==    by 0x428EC0: RTSPServer::rtspURLPrefix(int) const (in
/home/mt/live/testProgs/testOnDemandRTSPServer)
==26912==    by 0x428EEC: RTSPServer::rtspURL(ServerMediaSession
const*, int) const (in /home/mt/live/testProgs/testOnDemandRTSPServer)
==26912==    by 0x40223A: announceStream(RTSPServer*,
ServerMediaSession*, char const*, char const*) (in
/home/mt/live/testProgs/testOnDemandRTSPServer)
==26912==    by 0x4023AE: main (in
/home/mt/live/testProgs/testOnDemandRTSPServer)


Since "readSocket(UsageEnvironment" only exists in GroupsockHelper.cpp
and GroupsockHelper.hh, and there is only one select in the entire
file, I am pretty sure the delay happens at line 229 in
GroupsockHelper.cpp.

The server seems to also output a different IP address than the laptop
as well, laptop using eth0, while the server uses... eh, some other
address:

"mpeg4ESVideoTest" stream, from the file "test.m4e"
Play this stream using the URL "rtsp://127.0.1.1:8554/mpeg4ESVideoTest"

It seems from the trace that the ourSourceAddressForMulticast is the
sinner. Firstly, what does multicast have to do with the RTSP server?
Is that not purely unicast? Secondly, how can I remove this delay? It
is not critical, but quite annoying, especially the fact that my lousy
laptop "performs better" from the client point of view =)

As mentioned, running the exact same kernel, so multicast support
should be the same in both. They are the latest realtime kernels from
Ubuntu.

Thanks for any help with this.

-Morgan Torvolt-