On 14.05.2015 15:26, Richard Bell wrote: > Hi all, > > I'm working on an incredibly annoying issue related to my use of the > Header/Payload Demux (HPD) block. I think it's related to a buffer > overflow at some point, but I'm having a really hard time coming up with > a proper debug strategy to nail this down. > > What I'm seeing is my data streams freeze after the input to the HPD > block, both on the header branch and the payload branch. Everything > before the HPD block continues on without issue. The time it takes the > streams to freeze is HIGHLY variable. I've watched it run for 30 minutes > straight before a freeze and I've watched it freeze a few seconds after > start. I'm using tags generated by the Correlation Estimator as the > trigger for the HPD block. > > My question is this, if I suspect a buffer overflow is causing a freeze, > how would I prove this to myself?
Rich, a "buffer overflow" wouldn't cause GR to freeze, rather, it would crash. Going by your previous messages, I suspect what you're seeing is that the HPD is starting to block, causing backpressure until that in turn reaches the source. (Correct me if I'm wrong). I remember you previously mentioning something similar. Did you confirm the header parser is actually sending out a message for every data packet it receives? This is a case where the HPD is actually designed in a way that it'll fail. As a debugging strategy, I would recommend printing out the state changes inside the HPD state machine. If it freezes, it would be interesting to see in which state that is. Cheers, Martin _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
