TGBT18B_502_07 - Additional LBW tests


  • Test control and set up for coherent de-dispersion modes


  • M&C version switch began at 09:30
  • Submitted c0200x0128 at 09:54
    • OBSFREQ is correct but OBSNCHAN and OBSBW are still a factor of 4 too small
    • Ray is diagnosing
  • Ray fixed the shared memory parameters. Will try again
  • Submitted c0200x0128 at 10:30
    • OBSFREQ was incorrect on Bank C. Ray is fixing.
  • Ryan stepped out for a telecon and lunch at 10:50
  • Ryan returned at 13:05. Ray fixed OBSFREQ issue.
  • Taking a c0200x0128 scan at 13:09
    • Scans look OK. Tone is in right place, parameters are correct.
  • At first glance, c0100x0512 also looks OK
  • Going to step through all coherent LBW modes
    • Significant packet loss in c0100x0256 search. tint was 20.48 us
    • Significant packet loss in c0100x0512 search. tint was 20.48 us
    • NETSTAT blocked on Bank D during c0200x0512. tint was 40.96 us
    • Significant packet loss in c0200x0512. tint was 40.96 us
  • Tested frequencies for HBW coherent mode. Look OK.
  • Tried to go to an incoherent i0100x0512 mode to check switching signal control but Bank A manager seemed to crash.
    • Ray had accidentally made a change that set obs_nchan to zero for non-coherent modes. This is fixed now.
  • Ryan had to run to a telecon at 14:50, returned at 15:55
  • Ray and Joe are in process of switching back.
  • Checkout scans begin at 16:00. All looks good.


  • Coherent modes are looking good. Shared memory parameters are now correct. There are issues with dropped packets in certain modes. Should look into ways of mitigating this.
  • Didn't get a chance to test switching signals, but I think we are pretty close to being ready for regression testing.
-- RyanLynch - 2019-01-24
Topic revision: r3 - 2019-01-28, RyanLynch
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