WIP: Controller for low demand times

src/cobald/controller/timelord.py

@@ -0,0 +1,59 @@
+from datatime import datetime
+
+import trio
+
+from cobald.interfaces import Pool, Controller
+
+from cobald.daemon import service
+
+
+@service(flavour=trio)
+class TimelordController(Controller):
+    """
+    Time based Controller to test further demand in intervals. Between the intervals the demand set to zero.
+
+    :param target: the pool to manage
+    :param low_utilisation: pool utilisation below which resources are decreased
+    :param high_allocation: pool allocation above which resources are increased
+    :param rate: maximum change of demand in resources per second
+    :param interval: interval between adjustments in seconds
+    :param test_interval: test interval in seconds
+    :param test_intermission: interval between test interval in seconds
+    """
+
+    def __init__(
+        self, target: Pool, low_utilisation=0.5, high_allocation=0.5, rate=1, interval=1, test_interval=600,
+            test_intermission=3000,
+    ):
+        super().__init__(target=target)
+        assert rate > 0
+        self.rate = rate
+        self.interval = interval
+        assert low_utilisation <= high_allocation
+        self.low_utilisation = low_utilisation
+        self.high_allocation = high_allocation
+        assert test_intermission > 0
+        self.test_intermission = test_intermission
+        self.next_test_start_date = datatime.datetime.now()
+        assert test_interval > 0
+        self.test_interval = test_interval
+        self.update_test_date = False
+
+    async def run(self):
+        while True:
+            self.regulate(self.interval)
+            await trio.sleep(self.interval)
+
+    def regulate(self, interval):
+        if (self.next_test_start_date + self.test_interval) < datatime.datetime.now() and\
+                self.next_test_start_date > datetime.datetime.now():
+            self.update_test_date = True
+            if self.target.utilisation < self.low_utilisation:
+                self.target.demand -= interval * self.rate
+            elif self.target.allocation > self.high_allocation:
+                self.target.demand += interval * self.rate
+        else:
+            if self.update_test_date:
+                self.next_test_start_date += self.test_interval + self.test_intermission
+                self.update_test_date = False
+            self.target.demand = 0