<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">On 14 Jun 2017, at 1:32 PM, Baby Octopus <<a href="mailto:jagadishkamathk@gmail.com" class="">jagadishkamathk@gmail.com</a>> wrote:<div class=""><br class=""><div><blockquote type="cite" class=""><div class=""><div dir="ltr" style="font-family: LucidaGrande; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class="">Pipeline negotiation issue should be easy to debug. Have you enabled -v verbose mode. Do you see a particular element exposing caps which the next element may not support?</div></div></blockquote><div><br class=""></div><div>When you have a trivial static pipeline, sure.</div><div><br class=""></div><div>When you have a complex dynamic pipeline that is constructed on the fly based on the contents of the stream (and each stream has a different structure), and you end up with a pipeline of 69 elements in total, no, it is not easy to debug. Yes, we have used and have been completely swamped by the debug mode.</div><div><br class=""></div><div>What worked was to to analyse the status of the queues. As soon as we could see which queues were seeing data but empty, which queues were stuck, which queues had never seen data at all, the problem became obvious.</div><div><br class=""></div><div>Anyway, for the purposes of people arriving here in future from Google, use the patches I posted to see the status of the queues, you will in turn be able to explain whether a pipeline is legitimately stuck and why.</div><div><br class=""></div><div>Regards,</div><div>Graham</div><div>—</div><div><br class=""></div></div><br class=""></div></body></html>