Changeset 4552 for trunk/Ohana/src/opihi/doc/scheduler.txt

Timestamp:

Jul 14, 2005, 8:18:09 AM (21 years ago)

Author:

eugene

Message:

updating user commands

File:

• trunk/Ohana/src/opihi/doc/scheduler.txt (modified) (1 diff)

trunk/Ohana/src/opihi/doc/scheduler.txt

@@ +1 @@
+
+2005.07.14
+
+I am still exploring the scheduler / controller interactions.  the
+automatic interactions seem to work pretty well now.  The area of
+confusion is in the user interface, both in terms of checking on the
+status of things (both controller and scheduler) and in terms of
+having user control over aspects of the controller.
+
+I have defined user functions which execute the controller commands
+'status' and 'check'.  These are straightforeward since they simply
+send a command to the controller and echo the output (or give an error
+condition message).
+
+Should the user have the ability to define a job, independent of a
+task?  This could be implemented purely as a controller action: the
+controller commands 'job', 'kill', 'delete', 'stderr', 'stdout' would
+be available from the scheduler, and the commands simply passed
+along.  This adds a bit to the complexity: if the 'delete' command is
+passed along, nothing prevents the user from deleting a job scheduled
+by the scheduler from a task.  the scheduler may then get confused
+when it tries to interact with that job in the future from the
+automatic loop.
+
+Another option is to simply have these commands interact with the
+scheduler's job stack.  this has the advantage of limiting the
+scheduler / controller responsibility errors (scheduler, not user, is
+always responsible to sending/harvesting jobs to/from the
+controller, though we still need to handle the cases if a job is lost
+or dropped by the controller).  the diffficulty here is deciding how
+to handle the job completion.  we would need a way to define a set of
+exit macros, which could then do something useful with the output.  
+
+Another possibility is to define limits on how many times a task may
+spawn a job.  There would then be no 'job' function.  If we define
+this limitation, we will still need a way of killing and deleting a
+specific job.  Thus a 'kill' and 'delete' function would examine and
+modify the scheduler's job stack.  The stderr and stdout functions are
+then already part of the task commands.  
+
+Other task options might include: 
+
+- a list of allow / exclude time periods (which should be time-of-day
+  ranges and day-of-week ranges).
+
+- a function to delete an existing task (which would have to stop the
+  spawning of new jobs, at least until no more jobs for that task
+  remain).
+
+- allow the 'periods' command to define defaults when outside of a
+  task
+
+- 
 
 2005.07.05