[Asterisk-Users] Re: delays with IAX2 and Meetme

[Tony Mountifield]

In article <E1EPcnp-0002ek-IH at piglet.barn.za.net>,
Steven Langley <steven at intellinc.co.za> wrote:
> 
> I am using IAX2 softphones dialing into meetme conferences. I also have
> jitterbuffer=yes, with typical jitterbuffer settings. The problem I am
> having is that as soon as there is a delay from a participant, then the
> delay continues until the participant hangs up and dials in again. When
> dialing in again the delay seems to go.
> 
> It seems to me as though as soon as the server registers a delay from a
> participant, then it causes delay on all further packets from that
> participant.
> 
> Does anyone have any ideas what the problem could be?

Yes, there are a few possibilities. Firstly, are you using ztdummy for
timing? Which kernel version? If 2.6, have you ensured that USE_RTC is
correctly defined in ztdummy.c?

Look in bugs.digium.com at bug IDs 3599 and 4252 - they might be relevant.

Yesterday I found another mechanism which could give rise to both a delay
and broken audio - I found it with OH323 channels, but it might possibly
arise on other channel types too. It concerns a backlog building up in
the channel driver and never being drained by meetme because of blocking
in the pseudo-device when trying to write the contents of a large frame.

In app_meetme.c, try replacing this:

 careful_write(fd, f->data, f->datalen);

with this:

 if (f->datalen <= CONF_SIZE) {
   careful_write(fd, f->data, f->datalen);
 } else {
   ast_log(LOG_WARNING, "Discarding large frame (%d bytes) from channel %s\n", f->datalen, chan->name);
 }

and see if it helps.

I haven't yet submitted the above change to mantis.

Cheers
Tony
-- 
Tony Mountifield
Work: tony at softins.co.uk - http://www.softins.co.uk
Play: tony at mountifield.org - http://tony.mountifield.org