Hi,
Yes this is how currently rtpengine module re-detect rtpengines: during SIP routing processing. (e.g. rtpengine_manage())
Yes, lowering "rtpengine_tout_ms" will make rtpp_test() C code function take shorter time => rtpengine_manage() will take shorter time.
Also disabling "aggressive_redetection" modparam helps alot in case when no rtpengines available at all. Thus, redetection of unavailable rtpengine nodes is tried only when their time comes, based on "rtpengine_disable_tout" modparam. Right now, if no rtpengines available at all, and aggressive redetection is enabled(by default), redetection happens for each new SIP message, independent of "rtpengine_disable_tout" modparam. So delays SIP routing alot. (PR: https://github.com/kamailio/kamailio/pull/3992)
This way of detecting rtpengine has, of course, both pros and cons.
I've been thinking of adding another behavior of this node re-detection in code, guarded via new modparam: expose an rtpengine_ping() config function and call it from rtimer. And rtpengine_manage() function will just check if any nodes available, but not ping them anymore. => not sure how much time have for it though.
Thanks, Stefan
On 10/21/24 11:16, Christian Berger via sr-dev wrote:
Hi,
we had strange behavior with kamailio when some rtpengines were unreachable, so we looked into the the source code and found this in select_rtpp_node_new():
3323 /* Try to enable if it's time to try. */ 3324 if(node->rn_disabled && node->rn_recheck_ticks <= get_ticks()) { 3325 node->rn_disabled = rtpp_test(node, 1, 0); 3326 }
Does this mean that a ping will be done during rtpengine manage? Is this wise? I mean there are dedicated pings in the background. Doing this in rtpengine manage will only periodically delay the processing of a SIP message. We fear that in high traffic situations this could occupy all threads. Is this a bug?
As a workaround we think setting rtpengine_tout_ms to a lower value might help as it shortens the amount of time the module delays the processing of the SIP message.
What do you think?
Best wishes Christian Berger