Merge remote-tracking branch 'origin/store_fix' into export_import_disk

circle/circle/settings/base.py

@@ -576,7 +576,7 @@ SESSION_COOKIE_NAME = "csessid%x" % (((getnode() // 139) ^
 MAX_NODE_RAM = get_env_variable("MAX_NODE_RAM", 1024)
 MAX_NODE_CPU_CORE = get_env_variable("MAX_NODE_CPU_CORE", 10)
 
-SCHEDULER_METHOD = get_env_variable("SCHEDULER_METHOD", 'random')
+SCHEDULER_METHOD = get_env_variable("SCHEDULER_METHOD", 'advanced')
 
 # Url to download the client: (e.g. http://circlecloud.org/client/download/)
 CLIENT_DOWNLOAD_URL = get_env_variable('CLIENT_DOWNLOAD_URL', 'http://circlecloud.org/client/download/')
@@ -590,3 +590,12 @@ REQUEST_HOOK_URL = get_env_variable("REQUEST_HOOK_URL", "")
 SSHKEY_EMAIL_ADD_KEY = False
 
 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"))
+
+# Maximum time difference until the monitor's values get valid
+SCHEDULER_TIME_SENSITIVITY_IN_SECONDS = (
+    get_env_variable("SCHEDULER_TIME_SENSITIVITY_IN_SECONDS", "60"))

circle/dashboard/fixtures/node.json

@@ -65,7 +65,10 @@
     "modified": "2014-02-19T21:11:34.671Z", 
     "priority": 1, 
     "traits": [], 
-    "host": 1
+    "host": 1,
+    "ram_weight": 1.0,
+    "cpu_weight": 1.0,
+    "time_stamp":  "2017-12-13T21:08:08.819Z"
   }
 }
 ]

circle/dashboard/forms.py

@@ -1734,3 +1734,11 @@ class TwoFactorConfirmationForm(forms.Form):
         totp = pyotp.TOTP(self.user.profile.two_factor_secret)
         if not totp.verify(self.cleaned_data.get('confirmation_code')):
             raise ValidationError(_("Invalid confirmation code."))
+
+
+class AutoMigrationForm(forms.Form):
+    minute = forms.CharField()
+    hour = forms.CharField()
+    day_of_month = forms.CharField()
+    month_of_year = forms.CharField()
+    day_of_week = forms.CharField()

circle/dashboard/static/dashboard/dashboard.less

@@ -1079,6 +1079,10 @@ textarea[name="new_members"] {
   max-width: 100%;
 }
 
+#node-list-auto-migration-body {
+  padding: 20px;
+}
+
 #vm-list-table td.state,
 #vm-list-table td.memory {
   white-space: nowrap;

circle/dashboard/static/dashboard/node-list.js

@@ -3,4 +3,11 @@ $(function() {
     // find disabled nodes, set danger (red) on the rows
     $('.node-disabled').closest("tr").addClass('danger');
   });
+  $('#reschedule-now').click(function() {
+    $.get($(this).attr('href'), function(data){
+      highlight = data.result === 'ok' ? 'success' : 'danger';
+      addMessage(data.message, highlight);
+    });
+    return false;
+  });
 });

circle/dashboard/store_api.py

@@ -44,18 +44,12 @@ class NoStoreException(StoreApiException):
     pass
 
 
-class NoOrgIdException(StoreApiException):
-    pass
-
-
 class Store(object):
 
     def __init__(self, user, default_timeout=0.5):
         self.store_url = settings.STORE_URL
-        if not self.store_url:
+        if not self.store_url or not user.profile.org_id:
             raise NoStoreException
-        if not user.profile.org_id:
-            raise NoOrgIdException
         self.username = 'u-%s' % user.profile.org_id
         self.request_args = {'verify': settings.STORE_VERIFY_SSL}
         if settings.STORE_SSL_AUTH:

circle/dashboard/templates/dashboard/node-list.html

@@ -41,4 +41,23 @@
   </div><!-- -col-md-12 -->
 </div><!-- .row -->
 
+<div class="row">
+  <div class="col-md-12">
+    <div class="panel panel-default">
+      <div class="panel-heading">
+        <a id="reschedule-now" class="btn btn-danger pull-right" href="{% url "dashboard.views.reschedule" %}">
+          <i class="fa fa-magic"></i> {% trans "Reschedule now" %}
+        </a>
+        <h3 class="no-margin"><i class="fa fa-truck"></i> {% trans "Virtual machine auto migration" %}</h3>
+      </div>
+      <div id="node-list-auto-migration-body">
+        <h1>Crontab</h1>
+        <form>
+          {{ auto_migration_form.as_p }}
+        </form>
+      </div>
+    </div>
+  </div><!-- -col-md-12 -->
+</div><!-- .row -->
+
 {% endblock %}

circle/dashboard/urls.py

@@ -56,6 +56,7 @@ from .views import (
     MessageList, MessageDetail, MessageCreate, MessageDelete,
     EnableTwoFactorView, DisableTwoFactorView,
     AclUserGroupAutocomplete, AclUserAutocomplete,
+    RescheduleView,
 )
 from .views.vm import vm_ops, vm_mass_ops
 from .views.node import node_ops
@@ -153,6 +154,8 @@ urlpatterns = [
          r'(?P<time>[0-9]{1,2}[hdwy])$'),
         NodeListGraphView.as_view(),
         name='dashboard.views.node-list-graph'),
+    url(r'^node/reschedule/$', RescheduleView.as_view(),
+        name="dashboard.views.reschedule"),
     url((r'^template/(?P<pk>\d+)/graph/(?P<metric>[a-z]+)/'
          r'(?P<time>[0-9]{1,2}[hdwy])$'),
         TemplateGraphView.as_view(),

circle/dashboard/views/node.py

@@ -25,7 +25,7 @@ from django.core.exceptions import PermissionDenied
 from django.core.urlresolvers import reverse_lazy
 from django.db.models import Count
 from django.forms.models import inlineformset_factory
-from django.http import HttpResponse
+from django.http import HttpResponse, JsonResponse
 from django.shortcuts import redirect
 from django.template.loader import render_to_string
 from django.utils.translation import ugettext as _
@@ -37,11 +37,14 @@ from django_tables2 import SingleTableView
 from firewall.models import Host
 from vm.models import Node, NodeActivity, Trait
 from vm.tasks.vm_tasks import check_queue
+from vm.tasks.local_periodic_tasks import auto_migrate
 
-from ..forms import TraitForm, HostForm, NodeForm
+from ..forms import TraitForm, HostForm, NodeForm, AutoMigrationForm
 from ..tables import NodeListTable
 from .util import AjaxOperationMixin, OperationView, GraphMixin, DeleteViewBase
 
+from manager.mancelery import crontab_parser
+
 
 def get_operations(instance, user):
     ops = []
@@ -190,6 +193,14 @@ class NodeList(LoginRequiredMixin, GraphMixin, SingleTableView):
     table_class = NodeListTable
     table_pagination = False
 
+    def get_crontab(self):
+        return crontab_parser(settings.AUTO_MIGRATION_CRONTAB)
+
+    def get_context_data(self):
+        context = super(NodeList, self).get_context_data()
+        context["auto_migration_form"] = AutoMigrationForm(self.get_crontab())
+        return context
+
     def get(self, *args, **kwargs):
         if not self.request.user.has_perm('vm.view_statistics'):
             raise PermissionDenied()
@@ -367,3 +378,23 @@ class NodeActivityDetail(LoginRequiredMixin, SuperuserRequiredMixin,
         ).order_by('-started').select_related())
         ctx['icon'] = _get_activity_icon(self.object)
         return ctx
+
+
+class RescheduleView(SuperuserRequiredMixin, View):
+    def get(self, *args, **kwargs):
+        try:
+            auto_migrate.apply_async(queue='localhost.man.slow')
+        except Exception as e:
+            msg = str(e)
+            result = 'error'
+        else:
+            result = 'ok'
+            msg = _('Reschedule has started.')
+        if self.request.is_ajax():
+            return JsonResponse({'result': result, 'message': msg})
+        else:
+            if result == 'ok':
+                messages.success(self.request, msg)
+            else:
+                messages.error(self.request, msg)
+        return redirect('dashboard.views.node-list')

circle/dashboard/views/store.py

@@ -36,7 +36,7 @@ from django.views.generic import TemplateView
 from braces.views import LoginRequiredMixin
 
 from ..store_api import (Store, NoStoreException,
-                         NotOkException, NoOrgIdException)
+                         NotOkException)
 
 logger = logging.getLogger(__name__)
 
@@ -71,11 +71,6 @@ class StoreList(LoginRequiredMixin, TemplateView):
                 return super(StoreList, self).get(*args, **kwargs)
         except NoStoreException:
             messages.warning(self.request, _("No store."))
-        except NoOrgIdException:
-            messages.warning(self.request,
-                             _("Your organization ID is not set."
-                               " To use the store, you need a"
-                               " unique organization ID."))
         except NotOkException:
             messages.warning(self.request, _("Store has some problems now."
                                              " Try again later."))

circle/manager/mancelery.py

@@ -17,13 +17,27 @@
 
 from celery import Celery
 from celery.signals import worker_ready
+from celery.schedules import crontab
 from datetime import timedelta
 from celery.schedules import crontab
 from kombu import Queue, Exchange
 from os import getenv
 
+
 HOSTNAME = "localhost"
 QUEUE_NAME = HOSTNAME + '.man'
+AUTO_MIGRATION_CRONTAB = getenv('AUTO_MIGRATION_CRONTAB', '0 0 * * *')
+
+
+def crontab_parser(crontab):
+    fields = crontab.split(' ')
+    return dict(
+        minute=fields[0],
+        hour=fields[1],
+        day_of_month=fields[2],
+        month_of_year=fields[3],
+        day_of_week=fields[4],
+    )
 
 
 celery = Celery('manager',
@@ -56,6 +70,11 @@ celery.conf.update(
             'schedule': crontab(minute=10, hour=1),
             'options': {'queue': 'localhost.man'}
         },
+        'vm.local_periodic_tasks': {
+            'task': 'vm.tasks.local_periodic_tasks.auto_migrate',
+            'schedule': crontab(**crontab_parser(AUTO_MIGRATION_CRONTAB)),
+            'options': {'queue': 'localhost.man.slow'},
+        },
     }
 
 )

circle/manager/scheduler.py

@@ -15,15 +15,18 @@
 # You should have received a copy of the GNU General Public License along
 # with CIRCLE.  If not, see <http://www.gnu.org/licenses/>.
 
+import datetime
+import json
+import random
 from logging import getLogger
 
+from django.conf import settings
+from django.core.cache import cache
+from django.utils import timezone
 from django.utils.translation import ugettext_noop
 
-from common.models import HumanReadableException
-
 from circle.settings.base import SCHEDULER_METHOD
-
-import random
+from common.models import HumanReadableException
 
 logger = getLogger(__name__)
 
@@ -69,14 +72,14 @@ def common_select(instance, nodes):
         logger.warning('select_node: no enough RAM for %s', unicode(instance))
         raise NotEnoughMemoryException()
 
-    # sort nodes first by processor usage, then priority
+    # sort nodes first by priority
     nodes.sort(key=lambda n: n.priority, reverse=True)
-    nodes.sort(key=free_cpu_time, reverse=True)
     return nodes
 
 
 def common_evenly(instance, nodes):
     nodes = common_select(instance, nodes)
+    nodes.sort(key=free_cpu_time, reverse=True)
     result = nodes[0]
     return result
 
@@ -87,6 +90,16 @@ def common_random(instance, nodes):
     return result
 
 
+def advanced_with_time_stamp(instance, nodes):
+    nodes = common_select(instance, nodes)
+    nodes.sort(key=sorting_key, reverse=True)
+    logger.info("SCHEDLOG: {}".format(json.dumps({
+        "event": "after_sort", 
+        "list": map(lambda node: unicode(node), nodes)})))
+    result = nodes[0]
+    return result
+
+
 def select_node(instance, nodes):
     ''' Select a node for hosting an instance based on its requirements.
     '''
@@ -94,14 +107,72 @@ def select_node(instance, nodes):
         result = common_evenly(instance, nodes)
     elif SCHEDULER_METHOD == 'random':
         result = common_random(instance, nodes)
+    elif SCHEDULER_METHOD == 'advanced':
+        result = advanced_with_time_stamp(instance, nodes)
     else:  # Default method is the random
         result = common_random(instance, nodes)
 
-    logger.info('Scheduler method: %s selected', unicode(SCHEDULER_METHOD))
-    logger.info('select_node: %s for %s', unicode(result), unicode(instance))
+    logger.info("SCHEDLOG: {}".format(json.dumps(
+        {"event": "select",
+         "node": unicode(result),
+          "vm": unicode(instance)})))
+
+    set_time_stamp(result)
+
     return result
 
 
+def sorting_key(node):
+    """Determines how valuable a node is for scheduling.
+    """
+    key = 0
+    corr = last_scheduled_correction_factor(node)
+    if free_cpu_time(node) < free_ram(node):
+        key = free_cpu_time(node) * corr
+    else:
+        key = free_ram(node) * corr
+    logger.info("SCHEDLOG: {}".format(json.dumps({
+        "event": "sort",
+        "node": unicode(node),
+        "sorting_key": unicode(key),
+        "free_cpu_time": unicode(free_cpu_time(node)),
+        "free_ram": unicode(free_ram(node)),
+        "last_scheduled_correction_factor": unicode(last_scheduled_correction_factor(node))})))
+    return key
+
+
+def set_time_stamp(node):
+    cache.set('time_stamp{}'.format(node.id), timezone.now())
+
+
+def get_time_stamp(node):
+    time_stamp = cache.get('time_stamp{}'.format(node.id))
+    if time_stamp:
+        return time_stamp
+    return datetime.datetime(1970, 1, 1, tzinfo=timezone.get_current_timezone())
+
+
+def last_scheduled_correction_factor(node):
+    """Returns the time correction factor for a node.
+
+    The monitor data may be outdated, because of recent scheduling for a given node.
+    The return value is between 0 and 1, higher value indicates more time since the
+    last scheduling for the given node.
+    """
+    factor = 0
+    max_time_diff = settings.SCHEDULER_TIME_SENSITIVITY_IN_SECONDS
+    current_time = timezone.now()
+    time_difference_in_seconds = (
+        current_time - get_time_stamp(node)).total_seconds()
+    factor = time_difference_in_seconds/float(max_time_diff)
+    if factor > 1:
+        factor = 1
+    elif factor < 0:
+        factor = 1
+    logger.info('Scheduler set factor to %s', unicode(factor))
+    return factor
+
+
 def has_traits(traits, node):
     """True, if the node has all specified traits; otherwise, false.
     """
@@ -142,11 +213,27 @@ def free_cpu_time(node):
     Higher values indicate more idle time.
     """
     try:
-        activity = node.cpu_usage / 100
-        inactivity = 1 - activity
-        cores = node.num_cores
-        return cores * inactivity
+        free_cpu_percent = 1 - node.cpu_usage
+        weight = node.cpu_weight
+        weighted_value = free_cpu_percent * weight
+        return weighted_value
+    except TypeError as e:
+        logger.exception('Got incorrect monitoring data for node %s. %s',
+                         unicode(node), unicode(e))
+        return 0  # will result lowest priority
+
+
+def free_ram(node):
+    """Get an indicator number for free RAM on the node.
+
+    Higher value indicates more RAM.
+    """
+    try:
+        free_ram_percent = 1 - node.ram_usage
+        weight = node.ram_weight
+        weighted_value = free_ram_percent * weight
+        return weighted_value
     except TypeError as e:
-        logger.warning('Got incorrect monitoring data for node %s. %s',
+        logger.exception('Got incorrect monitoring data for node %s. %s',
                          unicode(node), unicode(e))
-        return False  # monitoring data is incorrect
+        return 0  # will result lowest priority

circle/vm/migrations/0003_auto_20171213_2018.py

+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.6 on 2017-12-13 20:18
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import django.utils.timezone
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('vm', '0002_interface_model'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='node',
+            name='cpu_weight',
+            field=models.FloatField(default=1.0, help_text='Indicates the relative CPU power of this node.', verbose_name='CPU Weight'),
+        ),
+        migrations.AddField(
+            model_name='node',
+            name='ram_weight',
+            field=models.FloatField(default=1.0, help_text='Indicates the relative RAM quantity of this node.', verbose_name='RAM Weight'),
+        ),
+        migrations.AddField(
+            model_name='node',
+            name='time_stamp',
+            field=models.DateTimeField(auto_now_add=True, default=django.utils.timezone.now, help_text='A timestamp for the node, used by the scheduler.', verbose_name='Last Scheduled Time Stamp'),
+            preserve_default=False,
+        ),
+    ]

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/models/node.py

@@ -30,7 +30,7 @@ from time import time, sleep
 from django.conf import settings
 from django.db.models import (
     CharField, IntegerField, ForeignKey, BooleanField, ManyToManyField,
-    FloatField, permalink, Sum
+    FloatField, DateTimeField, permalink, Sum
 )
 from django.utils import timezone
 from django.utils.translation import ugettext_lazy as _
@@ -128,11 +128,15 @@ class Node(OperatedMixin, TimeStampedModel):
     enabled = BooleanField(verbose_name=_('enabled'), default=False,
                            help_text=_('Indicates whether the node can '
                                        'be used for hosting.'))
-    schedule_enabled = BooleanField(verbose_name=_('schedule enabled'),
-                                    default=False, help_text=_(
+    schedule_enabled = BooleanField(
+        verbose_name=_('schedule enabled'),
+        default=False,
+        help_text=_(
             'Indicates whether a vm can be '
             'automatically scheduled to this '
-                                        'node.'))
+            'node.'
+        )
+    )
     traits = ManyToManyField(Trait, blank=True,
                              help_text=_("Declared traits."),
                              verbose_name=_('traits'))
@@ -140,6 +144,21 @@ class Node(OperatedMixin, TimeStampedModel):
     overcommit = FloatField(default=1.0, verbose_name=_("overcommit ratio"),
                             help_text=_("The ratio of total memory with "
                                         "to without overcommit."))
+    ram_weight = FloatField(
+        default=1.0,
+        help_text=_("Indicates the relative RAM quantity of this node."),
+        verbose_name=_("RAM Weight")
+    )
+    cpu_weight = FloatField(
+        default=1.0,
+        help_text=_("Indicates the relative CPU power of this node."),
+        verbose_name=_("CPU Weight")
+    )
+    time_stamp = DateTimeField(
+        auto_now_add=True,
+        help_text=_("A timestamp for the node, used by the scheduler."),
+        verbose_name=_("Last Scheduled Time Stamp")
+    )
 
     class Meta:
         app_label = 'vm'
@@ -162,7 +181,7 @@ class Node(OperatedMixin, TimeStampedModel):
             self.get_remote_queue_name("vm", "fast")
             self.get_remote_queue_name("vm", "slow")
             self.get_remote_queue_name("net", "fast")
-        except:
+        except Exception:
             return False
         else:
             return True
@@ -341,19 +360,25 @@ class Node(OperatedMixin, TimeStampedModel):
                 # Example:
                 # {"target": "circle.szianode.cpu.usage",
                 #  "datapoints": [[0.6, 1403045700], [0.5, 1403045760]
+                logger.info('MONITOR_TARGET: %s', target)
                 try:
                     metric = target['target']
                     if metric.startswith(prefix):
                         metric = metric[len(prefix):]
                     else:
+            	        logger.info('MONITOR_MET: %s %s', target, metric)
                         continue
+                    value = target['datapoints'][-1][0]
+                    if value is None: 
                         value = target['datapoints'][-2][0]
                     retval[metric] = float(value)
+                    logger.info('MONITOR_RETVAL: %s %s, %s', target['target'], metric, retval[metric])
                 except (KeyError, IndexError, ValueError, TypeError):
+                    logger.info('MONITOR_ERR: %s %s', metric, value)
                     continue
 
             return retval
-        except:
+        except Exception:
             logger.exception('Unhandled exception: ')
             return self.remote_query(vm_tasks.get_node_metrics, timeout=30,
                                      priority="fast")
@@ -416,7 +441,7 @@ class Node(OperatedMixin, TimeStampedModel):
         vm_state_changed hook.
         """
         domains = {}
-        domain_list = self.remote_query(vm_tasks.list_domains_info, timeout=5,
+        domain_list = self.remote_query(vm_tasks.list_domains_info, timeout=10,
                                         priority="fast")
         if domain_list is None:
             logger.info("Monitoring failed at: %s", self.name)
@@ -425,7 +450,7 @@ class Node(OperatedMixin, TimeStampedModel):
             # [{'name': 'cloud-1234', 'state': 'RUNNING', ...}, ...]
             try:
                 id = int(i['name'].split('-')[1])
-            except:
+            except Exception:
                 pass  # name format doesn't match
             else:
                 domains[id] = i['state']

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
@@ -33,7 +35,7 @@ def update_domain_states():
 
 
 @celery.task(ignore_result=True)
-def garbage_collector(timeout=15):
+def garbage_collector(offset=timezone.timedelta(seconds=20)):
     """Garbage collector for instances.
 
     Suspends and destroys expired instances.
@@ -42,8 +44,10 @@ def garbage_collector(timeout=15):
     :type timeout: int
     """
     now = timezone.now()
+    bw = 0
     for i in Instance.objects.filter(destroyed_at=None).all():
-        if i.time_of_delete and now > i.time_of_delete:
+        if i.time_of_delete and now > i.time_of_delete + offset and bw < 20:
+	    bw = bw + 1
             i.destroy.async(system=True)
             logger.info("Expired instance %d destroyed.", i.pk)
             try:
@@ -57,7 +61,8 @@ def garbage_collector(timeout=15):
                 logger.debug('Could not notify owner of instance %d .%s',
                              i.pk, unicode(e))
         elif (i.time_of_suspend and now > i.time_of_suspend and
-              i.state == 'RUNNING'):
+              i.state == 'RUNNING' and bw < 20):
+            bw = bw + 1
             logger.info("Expired instance %d suspended." % i.pk)
             try:
                 i.sleep.async(system=True)
@@ -77,4 +82,44 @@ def garbage_collector(timeout=15):
             logger.debug("Instance %d expires soon." % i.pk)
             i.notify_owners_about_expiration()
         else:
-            logger.debug("Instance %d didn't expire." % i.pk)
+            logger.debug("Instance %d didn't expire. bw:%d", i.pk, bw)
+
+
+@celery.task(ignore_result=True)
+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)