Periodically fetch for disk io stats

Change-Id: Id48337a598e8941d9e1793ad552251369ef3954f
Signed-off-by: Julien Danjou <julien.danjou@enovance.com>

bin/ceilometer-nova-compute

@@ -0,0 +1,39 @@
+#!/usr/bin/env python
+# -*- encoding: utf-8 -*-
+#
+# Copyright © 2012 eNovance <licensing@enovance.com>
+#
+# Author: Julien Danjou <julien@danjou.info>
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+import eventlet
+eventlet.monkey_patch()
+
+import sys
+
+from nova import flags
+from nova import log as logging
+from nova import service
+from nova import utils
+
+if __name__ == '__main__':
+    utils.default_flagfile()
+    flags.FLAGS(sys.argv)
+    logging.setup()
+    utils.monkey_patch()
+    server = service.Service.create(binary='ceilometer-nova-compute',
+                                    topic='ceilometer',
+                                    manager='ceilometer.nova.manager.ComputeManager')
+    service.serve(server)
+    service.wait()

ceilometer/nova/manager.py

@@ -16,9 +16,12 @@
 # License for the specific language governing permissions and limitations
 # under the License.
 
+from lxml import etree
+
 from nova import log as logging
 from nova import manager
 from nova import flags
+import nova.virt.connection
 
 # Import rabbit_notifier to register notification_topics flag
 import nova.notifier.rabbit_notifier
@@ -40,3 +43,25 @@ class InstanceManager(manager.Manager):
     def _on_notification(self, body):
         event_type = body.get('event_type')
         LOG.info('NOTIFICATION: %s', event_type)
+
+
+class ComputeManager(manager.Manager):
+    def _get_disks(self, conn, instance):
+        """Get disks of an instance, only used to bypass bug#998089."""
+        domain = conn._conn.lookupByName(instance)
+        tree = etree.fromstring(domain.XMLDesc(0))
+        return filter(bool,
+                      [target.get('dev') \
+                           for target in tree.findall('devices/disk/target')])
+
+    @manager.periodic_task
+    def _fetch_diskio(self, context):
+        if FLAGS.connection_type == 'libvirt':
+            conn = nova.virt.connection.get_connection(read_only=True)
+            for instance in self.db.instance_get_all_by_host(context,
+                                                             self.host):
+                # TODO(jd) This does not work see bug#998089
+                # for disk in conn.get_disks(instance.name):
+                for disk in self._get_disks(conn, instance.name):
+                    stats = conn.block_stats(instance.name, disk)
+                    LOG.info("DISKIO USAGE: %s %s: read-requests=%d read-bytes=%d write-requests=%d write-bytes=%d errors=%d" % (instance, disk, stats[0], stats[1], stats[2], stats[3], stats[4]))