Re: Number of samples processed in the work function

[Marcus Müller]

Also a very good solution, but requires that you always get exactly 1024 items, not 
sometimes 1024, and in some cases 100, or 1023.

On 28.06.22 19:13, WarMonkey wrote:
> I think "processing more samples" should be prohibited because the length of each buffer 
> is limited.
> Use "set_output_multiple()" function to keep noutput_items equal to N*output_multiple (N 
> is a positive integer).
> https://www.gnuradio.org/doc/doxygen/classgr_1_1block.html#a63d67fd758b70c6f2d7b7d4edcec53b3 
> <https://www.gnuradio.org/doc/doxygen/classgr_1_1block.html#a63d67fd758b70c6f2d7b7d4edcec53b3>
>
>
> Perkins, Daniel (US) <perkinsd@battelle.org <mailto:perkinsd@battelle.org>> 于2022年6月29 
> 日周三 00:47写道：
>
>     I have written a source block that reads an IQ data stream from a socket. 
> ____
>
>     It is my understanding that:____
>
>       * the work function should attempt to process the number of samples as 
> determined by
>         the noutput_items variable____
>       * processing fewer samples is acceptable____
>       * processing more samples is not recommended____
>
>     __ __
>
>     My socket packets contain a fixed number of samples so to avoid an extra 
> memory
>     transfer, I prefer to copy straight from the socket buffer directly to the 
> output
>     buffer with a volk function.  To make this work, I need to return that 
> number (1024)
>     of samples from the work function which sometimes violates the “processing 
> more
>     samples” rule.  However, this seems to work without any issues and only the 
> occasional
>     dropped UDP frame.  I can also manipulate what GNU Radio will assign to 
> noutput_items
>     by calling  set_min_noutput_items.  When I set the min nouput_items to the 
> size of my
>     payload, I get a bunch of underruns.  What is the optimal way to deal with 
> this?____