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<p class="MsoNormal">Running Asterisk 16.17.0<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We have an interesting scenario where we see Asterisk CPU usage spike to the point the entire system is maxed out.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">There is a specific scenario where we have two ConfBridges and they are connected via a local channel. Everything is fine here.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Callers <-> ConfBridge A <-> local channel <-> ConfBridge B <-> Callers<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We may be recording both ConfBridges for different groups. Again, all is fine.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Where we run into a problem is when someone decides they need to record a response. We connect another local channel to the ConfBridge. All is fine.<o:p></o:p></p>
<p class="MsoNormal">Callers <-> ConfBridge A <-> local channel <-> ConfBridge B <-> Callers<o:p></o:p></p>
<p class="MsoNormal"> <-> Local Channel<o:p></o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
<p class="MsoNormal">Then, we initiate a record on the other end of the local channel.<o:p></o:p></p>
<p class="MsoNormal">Callers <-> ConfBridge A <-> local channel <-> ConfBridge B <-> Callers<o:p></o:p></p>
<p class="MsoNormal"> <-> Local Channel (start recording)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Suddenly, the CPU usage spikes to the point the system is starving and gradually gets worse.<o:p></o:p></p>
<p class="MsoNormal">Looking at the debug log for Asterisk, we are seeing thousands of messages like this (roughly 8-10 sets every millisecond)<o:p></o:p></p>
<p class="MsoNormal">[05/05 10:25:28.541] DEBUG[2981][C-00000038] chan_pjsip.c: PJSIP/1003-00000007: Indicated Video Update<o:p></o:p></p>
<p class="MsoNormal">[05/05 10:25:28.541] DEBUG[2981][C-00000038] chan_pjsip.c: PJSIP/1003-00000007<o:p></o:p></p>
<p class="MsoNormal">[05/05 10:25:28.541] DEBUG[2981][C-00000038] chan_pjsip.c: PJSIP/1003-00000007: Indicated Video Update<o:p></o:p></p>
<p class="MsoNormal">[05/05 10:25:28.541] DEBUG[2981][C-00000038] chan_pjsip.c: PJSIP/1003-00000007<o:p></o:p></p>
<p class="MsoNormal">[05/05 10:25:28.541] DEBUG[2981][C-00000038] chan_pjsip.c: PJSIP/1003-00000007: Indicated Video Update<o:p></o:p></p>
<p class="MsoNormal">[05/05 10:25:28.541] DEBUG[2981][C-00000038] chan_pjsip.c: PJSIP/1003-00000007<o:p></o:p></p>
<p class="MsoNormal">[05/05 10:25:28.541] DEBUG[2981][C-00000038] chan_pjsip.c: PJSIP/1003-00000007: Indicated Video Update<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">After this occurs, the messages in the debug output can also be a bit out of order for the date/time listed in the file.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">An interesting scenario, if we first start recording on the Local channel, then add it to the ConfBridge this CPU spike does not occur.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We realize this is a bit of an extreme scenario, two ConfBridges connected with a local channel, and needing to connect another local channel to one of the ConfBridges and start recording. Unfortunately, it’s a scenario we are stuck with
due to a unique customer requirement.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Any thoughts or suggestions?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Dan<o:p></o:p></p>
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