Re: [Discuss-gnuradio] Performance drop with upgrade to 3.7

[Luke Berndt]

Thanks - I am running an quad-core Intel I5 laptop. It is running Ubuntu 13.10. I also have it running on a VM on my 8 Core I7 Macbook.

Do you have any pointers or links on using oprofile with gnuradio? I found some material on using GR Performance Counters, but I haven't had a chance to try. 

I am going to working on learning how to profile using the VM. In the meantime, I rolled back the bare metal machine so I can keep my site up.

I installed 3.7 using the build-gnuradio script. When I reinstalled 3.6.5, also using build-gnuradio, the performance was still high. I am wondering if it actually has something to do with libraries being upgraded. I know the script upgraded me from Boost 1.49 to 1.53. Are there some other libraries that could have a perf impact? ITPP?

On Mon, Mar 24, 2014 at 11:35 AM, West, Nathan <address@hidden> wrote:

On Mon, Mar 24, 2014 at 7:17 AM, Luke Berndt <address@hidden> wrote:
> 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
>
>
>
>

What processor and OS are you running on? I suggest you start by
profiling your flowgraphs with something like oprofile/perf or control
port. Profiling with 3.7 is the first step and may be all that's
necessary if something really stands out, otherwise comparing results
of 3.6.5.1 and 3.7 would be good.

I'd be interested in seeing your results.


Nathan