[Discuss-gnuradio] Performance drop with upgrade to 3.7

[Luke Berndt]

Hi - I just upgraded to 3.7.3 using the build-gnuradio script from 3.6.5.1. I am using it to run a C++ App that captures all the radio communications on a Moto SmartNet system. I upgraded all my code to work with the 3.7 naming scheme and got everything to compile and run. Everything runs in 3.7, but I am seeing a lot more CPU usage, almost a whole additional core.

Are there an obvious things I should check where blocks changed significantly from 3.6 to 3.7? 

The main code is here:

https://github.com/robotastic/smartnet-recorder/tree/3.7

And the codec is here:

https://github.com/robotastic/gr-dsd/tree/3.7

I put together the general flow graph below. Are there any blocks where I could be shooting myself in the foot? Is it better to do xlating or sig_source & multiply_cc? The source bandwidth is 5MHz.

Decode Control Channel: [ https://github.com/robotastic/smartnet-recorder/blob/3.7/smartnet.cc ]

multiply_cc ( OsmoSDR(HackRF)  +    analog::sig_source_c )

gr::filter::fir_filter_ccf

gr::digital::fll_band_edge_cc

gr::analog::pll_freqdet_cf

gr::digital::clock_recovery_mm_ff

gr::digital::binary_slicer_fb

gr::digital::correlate_access_code_tag_bb

smartnet_deinterleave

smartnet_crc

Decode digital voice channel: [ https://github.com/robotastic/smartnet-recorder/blob/3.7/logging_receiver_dsd.cc ]

tb->connect( OsmoSDR(HackRF) )

gr::filter::freq_xlating_fir_filter_ccf

gr::filter::rational_resampler_base_ccf

gr::analog::quadrature_demod_cf

gr::filter::fir_filter_fff

dsd_make_block_ff [ https://github.com/robotastic/gr-dsd/blob/3.7/lib/dsd_block_ff.cc ]

gr::blocks::wavfile_sink