Verification Datasets Meeting 2015-12-23 Minutes

Verification Datasets Meeting 2015-12-23 Minutes
Attendees: David, Angelo, Simon, RHL, Gruendl, Russell
Regrets: Colin


  • diagnostic plot on # of failures vs. number of sources per ccd
  • lots of failures everywhere, but failures quickly rises above ~2000 sources per ccd
  • RHL mentioned that there are diagnostic plots, but Simon thinks it might be hard if there are calibration errors
  • Angelo will make an ipython notebook that shows how he did things
  • RHL suggests turninng on “–debug” and setting to turn on the debug plots
    documentation on how to use the debug option
    go to “AstrometryTask” and “Debug Variables”
  • debug-level bugging, --loglevel debug, can set component names, trace level with a negative integer
    --loglevel processCcdDecam.calibrate.astrometry=debug
    • there is ds9 debug ported from HSC side
    • trace gives you more verbosity levels of information, but this might not give more information than using debug
    • work is being done on developing multiple levels of debug or trace, RHL will post a community post on this to sort this out
  • to show just the astrometry config parameters and documentation . --show config="*calibrate.astrometry*"
  • do the icSrc files get written if the astrometry fails? no
  • Angelo will send command to produce the failure and RHL will look at it
  • not finding the faintest sources for the ones that failed, check detection config values
  • what threshold is that? global sigma, local sigma
    config.detection.thresholdType='stdev' global value
  • should use “pixel_stdev” which will use a per pixel variance value


  • OpenBlas performance issue
    • was running 40 processCcdDecam jobs on new linux machine and got very bad performance
    • JMatt and I tracked it down, it was an OpenBlas problem (dependency of numpy that miniconda installs)
    • OpenBlas uses all possible cores by default, so all processes were trying to use all cores and so 5120 threads were created and all the time was spent swapping
    • see ticket
    • the consensus was that the workflow system should set the appropriate global environmental variable (I’ve already implemented this in my IDL workflow) and that this problem needs to be documented.
    • JMatt will make a post on community over the holidays on this
  • John Swinbank fixed the LTV1/2 error in afw (thanks!), need to rerun processCcdDecam on all images
  • discovered that showVisitSkyMap doesn’t actually print out the information that I need and does a crude overlap checking of visits and patches. I’m making a modified version called printVisitSkyMap that will print out visit, ccd, tract and patch for all ccd+patch overlaps.
  • giving talk at AAS (at NSF pavilion) on verification work, thanks to everyone that sent figures!

Colin (not on but sent in update):

  • Turning on dipole measurement, including sorting out the numerous warning messages that result, and understanding the output catalogs.
  • Automating the pairing of exposures to difference. This might mean generating “templates” that the stack recognizes.

Francisco/Yusra: not on
Dominique: not on
Michael Wood-Vasey: not on

No call until after the AAS