See: https://wiki.gnuradio.org/index.php/Tagged_Stream_Blocks https://wiki.gnuradio.org/index.php/Stream_Tags
It's a little confusing at first that they're called Stream Tags and Tagged Streams. On Tue, Nov 24, 2020 at 11:35 AM Jeff Long <[email protected]> wrote: > A tag is a piece of metadata that points to a specific sample in a stream. > Tagged streams operate on chunks of samples, using a certain tag to > determine the chunk length. Streams are simpler to deal with, unless you > need data chunked. > > What kind of performance issues are you finding? > > If you are implementing a block, and do not want tags passed through, > `set_tag_propagation_policy(TPP_DONT)`. > > On Mon, Nov 23, 2020 at 3:55 PM Nicholas Long <[email protected]> > wrote: > >> Hi, So I am not sure exactly how to ask this, but I have a few questions >> about tag best practices when creating OOT modules, apologies if this is >> answered elsewhere... >> >> What is the main source of performance issues with tag propagation: Is it >> primarily copying overhead? Are there contention issues? or is most of the >> overhead in the actual reading/setting of tags? I guess part of my question >> is how are tags passed between blocks, I understand the ring buffers, but >> tags are still somewhat a mystery to me. >> >> Are tagged stream blocks better than just a stream with tags? From my >> limited ability to parse tagged stream blocks seem to limit the number of >> calls to get_tags_in_range, but they still pass on all other tags on the >> input buffer to the output buffer regardless. >> >> Thanks, >> Nick >> >
