Added periodic task for vm auto migration

circle/circle/settings/base.py

@@ -590,3 +590,5 @@ TWO_FACTOR_ISSUER = get_env_variable("TWO_FACTOR_ISSUER", "CIRCLE")
 
 # Default value is every day at midnight
 AUTO_MIGRATION_CRONTAB = get_env_variable("AUTO_MIGRATION_CRONTAB", "0 0 * * *")
+AUTO_MIGRATION_TIME_LIMIT_IN_HOURS = (
+    get_env_variable("AUTO_MIGRATION_TIME_LIMIT_IN_HOURS", "2"))

circle/vm/models/instance.py

@@ -865,6 +865,53 @@ class Instance(AclBase, VirtualMachineDescModel, StatusModel, OperatedMixin,
     def metric_prefix(self):
         return 'vm.%s' % self.vm_name
 
+
+    class MonitorUnavailableException(Exception):
+        """Exception for monitor_info()
+
+            Indicates the unavailability of the monitoring server.
+        """
+        pass
+
+    def monitor_info(self):
+        metrics = ('cpu.percent', 'memory.usage')
+        prefix = self.metric_prefix
+        params = [('target', '%s.%s' % (prefix, metric))
+                  for metric in metrics]
+        params.append(('from', '-5min'))
+        params.append(('format', 'json'))
+
+        try:
+            logger.info('%s %s', settings.GRAPHITE_URL, params)
+            response = requests.get(settings.GRAPHITE_URL, params=params)
+
+            retval = {}
+            for target in response.json():
+                # Example:
+                # {"target": "circle.vm.{name}.cpu.usage",
+                #  "datapoints": [[0.6, 1403045700], [0.5, 1403045760]
+                try:
+                    metric = target['target']
+                    if metric.startswith(prefix):
+                        metric = metric[len(prefix):]
+                    else:
+                        continue
+                    value = target['datapoints'][-2][0]
+                    retval[metric] = float(value)
+                except (KeyError, IndexError, ValueError):
+                    continue
+
+            return retval
+        except Exception:
+            logger.exception('Monitor server unavailable: ')
+            raise Instance.MonitorUnavailableException()
+
+    def cpu_usage(self):
+        return self.monitor_info().get('cpu.percent')
+
+    def ram_usage(self):
+        return self.monitor_info().get('memory.usage')
+
     @contextmanager
     def activity(self, code_suffix, readable_name, on_abort=None,
                  on_commit=None, task_uuid=None, user=None,

circle/vm/tasks/local_periodic_tasks.py

@@ -17,7 +17,9 @@
 
 import logging
 from django.utils import timezone
+from datetime import timedelta
 from django.utils.translation import ugettext_noop
+from django.conf import settings
 
 from manager.mancelery import celery
 from vm.models import Node, Instance
@@ -79,8 +81,40 @@ def garbage_collector(timeout=15):
 
 
 @celery.task(ignore_result=True)
-def auto_migrate():  # Dummy implementation
-    import time
-    logger.info("Auto migration has started.")
-    time.sleep(10)
-    logger.info("Auto migration has finished.")
+def auto_migrate():
+    """Auto migration task for runtime scaling
+    """
+    time_limit = settings.AUTO_MIGRATION_TIME_LIMIT_IN_HOURS
+    available_time = timedelta(hours=int(time_limit))
+    deadline = timezone.now() + available_time
+    while timezone.now() < deadline:
+        migrate_one()
+
+
+def migrate_one():
+    """Migrate a VM syncronously.
+
+        The target node chosen by the scheduler.
+    """
+    nodes = [n for n in Node.objects.filter(enabled=True) if n.online]
+    node_max_cpu = max(nodes, key=lambda x: x.cpu_usage / x.cpu_weight)
+    node_max_ram = max(nodes, key=lambda x: x.ram_usage / x.ram_weight)
+    if node_max_cpu.cpu_usage > node_max_ram.ram_usage:
+        try:
+            instance_to_migrate = max(Instance.objects.filter(node=node_max_cpu.pk),
+                                      key=lambda x: x.cpu_usage())
+            instance_to_migrate.migrate(system=True)
+        except Instance.MonitorUnavailableException:
+            instance_to_migrate = max(Instance.objects.filter(node=node_max_cpu.pk),
+                                      key=(lambda x: x.get_vm_desc()["vcpu"] *
+                                           x.get_vm_desc()["cpu_share"]))
+            instance_to_migrate.migrate(system=True)
+    else:
+        try:
+            instance_to_migrate = max(Instance.objects.filter(node=node_max_ram.pk),
+                                      key=lambda x: x.ram_usage())
+            instance_to_migrate.migrate(system=True)
+        except Instance.MonitorUnavailableException:
+            instance_to_migrate = max(Instance.objects.filter(node=node_max_cpu.pk),
+                                      key=lambda x: x.get_vm_desc()["memory"])
+            instance_to_migrate.migrate(system=True)