I installed Asterisk 1.6.2 (from debian squeeze) inside a domU with Debian Lenny. I also compiled and loaded the dahdi_dummy module into the domU, in order to get a more accurate timing.
The same Asterisk was installed also in the dom0, exactly the same configuration, also with dahdi_dummy.
In order to test jitter buffer skew on another sip pbx (not asterisk) I make two simultaneous call to dom0 and domU, calling an extension that will play a long audio file (about 90 minutes)
Well, after six minutes I noticed in the domU asterisk console the following message:
ERROR: res_timing_timerfd.c:169 timerfd_timer_ack: Read error: Resource temporarily unavailable
In the caller PBX i saw that the jitter buffer is quite larger for the virtual asterisk that for the dom0 one, 140ms vs 340ms (after 1 hour of playback)
I didn’t find anything googling for such error, so I’m going to ask here.