scheduler: simplify priority policy

Remove overdueness. User must submit calibration experiments with higher priority values for them to take precedence.

artiq/frontend/artiq_client.py

@@ -138,8 +138,8 @@ def _show_schedule(schedule):
     clear_screen()
     if schedule:
         l = sorted(schedule.items(),
-                   key=lambda x: (x[1]["due_date"] or 0,
+                   key=lambda x: (-x[1]["priority"],
-                                  -x[1]["priority"],
+                                  x[1]["due_date"] or 0,
                                   x[0]))
         table = PrettyTable(["RID", "Pipeline", "    Status    ", "Prio",
                              "Due date", "File", "Experiment", "Arguments"])

artiq/gui/schedule.py

@@ -17,8 +17,8 @@ class _ScheduleModel(DictSyncModel):
             parent, init)
 
     def sort_key(self, k, v):
-        # order by due date, and then by priority and RID
+        # order by priority, and then by due date and RID
-        return (v["due_date"] or 0, -v["priority"], k)
+        return (-v["priority"], v["due_date"] or 0, k)
 
     def convert(self, k, v, column):
         if column == 0:

artiq/master/scheduler.py

@@ -81,14 +81,16 @@ class Run:
             self._notifier[self.rid]["status"] = self._status.name
 
     # The run with the largest priority_key is to be scheduled first
-    def priority_key(self, now):
+    def priority_key(self, now=None):
         if self.due_date is None:
-            overdue = 0
             due_date_k = 0
         else:
-            overdue = int(now > self.due_date)
             due_date_k = -self.due_date
-        return (overdue, self.priority, due_date_k, -self.rid)
+        if now is not None and self.due_date is not None:
+            runnable = int(now > self.due_date)
+        else:
+            runnable = 1
+        return (runnable, self.priority, due_date_k, -self.rid)
 
     @asyncio.coroutine
     def close(self):
@@ -240,10 +242,9 @@ class RunStage(TaskObject):
                 next_irun = asyncio_queue_peek(self.inq)
             except asyncio.QueueEmpty:
                 next_irun = None
-            now = time()
             if not stack or (
                     next_irun is not None and
-                    next_irun.priority_key(now) > stack[-1].priority_key(now)):
+                    next_irun.priority_key() > stack[-1].priority_key()):
                 stack.append((yield from self.inq.get()))
 
             run = stack.pop()