
2014.02.06

** a single region-level host owns images for which the center lands
   in its region.

** it owns detections which come from images which it owns
   
** it owns objects which land in its region

Extending parallel relphot processing to split the sky (and images)
into regions, each of which runs in parallel at the same time:

Top Level (relphot -parallel-images):
 * define regions of the sky -> hosts
 * load images, assign to hosts
 * launch region-level jobs on remote hosts

 Region Level (relphot -parallel-images-region)
  * load my image subset table
  * request objects and detections for my skyregion
  * match images & objects, etc

  * update my image parameters
  * update my detections
  * write out detections 
  * load detections from my border hosts
  * match to my objects
  * update my objects
  * write out objects
  * load objects from my border hosts
  * update images
    (iterate N times)
  * write out image parameters

Top Level
  * read image parameters, update
  * update objects

2012.02.13

Image fields needed by relphot_client (saved by ImageSubsetSave):

imageID
photom_map_id
flags
Mcal
dMcal
tzero
trate

(if we have USE_GRID == T):
photcode


2012.02.10

I have put together the start of parallel dvo examples.  I have
'dvodist' to distribute the data (and pull it back), and parallel
modifications to 'setphot'.  Here is what I need to do to relphot to
make it work in parallel:

* load_catalogs.c : a parallel version of this would spawn the remote
  jobs in -load mode.  these should read from their owned tables,
  collect the subset of detections (subset naturally generated by
  bcatalog), and write the results to local temp fits files.  the main
  program would wait until the sub programs have been finished and
  then load in all of the subset tables.

* reload_catalogs : a parallel version needs to write the subset image
  table and then run the remote jobs.  these would read the image
  data, and load and update their local database tables.  This is
  nearly identical to the code in setphot / setphot_client.
