"MDSplus Event Management System" (MEMS) runs on Linux and allows the summation
(Boolean operations) on MDSplus events and notification via new events.

See http://w3.pppl.gov/~bdavis/swdoc/Event_Summation_System_Abstract.pdf

To start it:

   ssh skylark
   
     sudo  /etc/init.d/startstop_mems restart


to see the status (only from skylark):

   cd /p/tdi/nstxops/bin/MEMS
   ./idlMEMSserver status -v

   if OK should see:
   
      num child1= 1: 

      num child2= 2: 

      Status of idlMEMSserver:
       OK
 
To add or modify dependencies, edit the file 
/p/tdi/nstxops/bin/MEMS/NSTX_DEPENDENCIES.MEMS

everything is logged in /p/tdi/nstxops/bin/MEMS/log/idlMEMSserver.log
--------------------------------------------------------------

Running status of MEMS is checked every 5 minutes by sentry. 

See http://nstx.pppl.gov/nstx/Software/pdf_files/MDS_Event_Summation.pdf
for a data flow of the system.

To add or modify dependencies, edit the file 
/p/tdi/nstxops/bin/MEMS/NSTX_DEPENDENCIES.MEMS

Conventions within the NSTX_DEPENDENCIES.MEMS:

  "/OWN:person" is only used for documentation purposes, and is optional.
  "/EPICS will cause the resulting event to be passed along to EPICS via a CUPUT.
  "NONE" events will not get summed by MEMS. Their "result" will just get passed
       to EPICS.


NOTE: if the server to which these Event-summation tasks are connect 
      (skylark by default) go down, the tasks don't notice any errors, but
      no longer get events. They need to be restarted manually. In the
      future, this will be automated.

(Last edited 02-Jun-2017, by Bill Davis)