Merge "Eliminates simultaneous schedule race."

4 files changed, 35 insertions, 21 deletions

diff --git a/nova/scheduler/host_manager.py b/nova/scheduler/host_manager.py
index 4727c4706..fc9f3c8cc 100644
--- a/nova/scheduler/host_manager.py
+++ b/nova/scheduler/host_manager.py
@@ -96,15 +96,8 @@ class HostState(object):
     def __init__(self, host, topic, capabilities=None, service=None):
         self.host = host
         self.topic = topic
+        self.update_capabilities(topic, capabilities, service)
 
-        # Read-only capability dicts
-
-        if capabilities is None:
-            capabilities = {}
-        self.capabilities = ReadOnlyDict(capabilities.get(topic, None))
-        if service is None:
-            service = {}
-        self.service = ReadOnlyDict(service)
         # Mutable available resources.
         # These will change as resources are virtually "consumed".
         self.total_usable_disk_gb = 0
@@ -130,8 +123,22 @@ class HostState(object):
         # Resource oversubscription values for the compute host:
         self.limits = {}
 
+        self.updated = None
+
+    def update_capabilities(self, topic, capabilities=None, service=None):
+        # Read-only capability dicts
+
+        if capabilities is None:
+            capabilities = {}
+        self.capabilities = ReadOnlyDict(capabilities.get(topic, None))
+        if service is None:
+            service = {}
+        self.service = ReadOnlyDict(service)
+
     def update_from_compute_node(self, compute):
         """Update information about a host from its compute_node info."""
+        if self.updated and self.updated > compute['updated_at']:
+            return
         all_ram_mb = compute['memory_mb']
 
         # Assume virtual size is all consumed by instances if use qcow2 disk.
@@ -148,6 +155,7 @@ class HostState(object):
         self.free_disk_mb = free_disk_mb
         self.vcpus_total = compute['vcpus']
         self.vcpus_used = compute['vcpus_used']
+        self.updated = compute['updated_at']
 
         stats = compute.get('stats', [])
         statmap = self._statmap(stats)
@@ -191,6 +199,7 @@ class HostState(object):
         self.free_ram_mb -= ram_mb
         self.free_disk_mb -= disk_mb
         self.vcpus_used += vcpus
+        self.updated = timeutils.utcnow()
 
         # Track number of instances on host
         self.num_instances += 1
@@ -270,6 +279,7 @@ class HostManager(object):
 
     def __init__(self):
         self.service_states = {}  # { <host> : { <service> : { cap k : v }}}
+        self.host_state_map = {}
         self.filter_classes = filters.get_filter_classes(
                 FLAGS.scheduler_available_filters)
 
@@ -341,8 +351,6 @@ class HostManager(object):
             raise NotImplementedError(_(
                 "host_manager only implemented for 'compute'"))
 
-        host_state_map = {}
-
         # Get resource usage across the available compute nodes:
         compute_nodes = db.compute_node_get_all(context)
         for compute in compute_nodes:
@@ -352,10 +360,15 @@ class HostManager(object):
                 continue
             host = service['host']
             capabilities = self.service_states.get(host, None)
-            host_state = self.host_state_cls(host, topic,
-                    capabilities=capabilities,
-                    service=dict(service.iteritems()))
+            host_state = self.host_state_map.get(host)
+            if host_state:
+                host_state.update_capabilities(topic, capabilities,
+                                               dict(service.iteritems()))
+            else:
+                host_state = self.host_state_cls(host, topic,
+                        capabilities=capabilities,
+                        service=dict(service.iteritems()))
+                self.host_state_map[host] = host_state
             host_state.update_from_compute_node(compute)
-            host_state_map[host] = host_state
 
-        return host_state_map
+        return self.host_state_map
diff --git a/nova/tests/scheduler/fakes.py b/nova/tests/scheduler/fakes.py
index 29466fbe1..ba255c32c 100644
--- a/nova/tests/scheduler/fakes.py
+++ b/nova/tests/scheduler/fakes.py
@@ -28,19 +28,19 @@ from nova.scheduler import host_manager
 COMPUTE_NODES = [
         dict(id=1, local_gb=1024, memory_mb=1024, vcpus=1,
              disk_available_least=512, free_ram_mb=512, vcpus_used=1,
-             free_disk_mb=512, local_gb_used=0,
+             free_disk_mb=512, local_gb_used=0, updated_at=None,
              service=dict(host='host1', disabled=False)),
         dict(id=2, local_gb=2048, memory_mb=2048, vcpus=2,
              disk_available_least=1024, free_ram_mb=1024, vcpus_used=2,
-             free_disk_mb=1024, local_gb_used=0,
+             free_disk_mb=1024, local_gb_used=0, updated_at=None,
              service=dict(host='host2', disabled=True)),
         dict(id=3, local_gb=4096, memory_mb=4096, vcpus=4,
              disk_available_least=3072, free_ram_mb=3072, vcpus_used=1,
-             free_disk_mb=3072, local_gb_used=0,
+             free_disk_mb=3072, local_gb_used=0, updated_at=None,
              service=dict(host='host3', disabled=False)),
         dict(id=4, local_gb=8192, memory_mb=8192, vcpus=8,
              disk_available_least=8192, free_ram_mb=8192, vcpus_used=0,
-             free_disk_mb=8192, local_gb_used=0,
+             free_disk_mb=8192, local_gb_used=0, updated_at=None,
              service=dict(host='host4', disabled=False)),
         # Broken entry
         dict(id=5, local_gb=1024, memory_mb=1024, vcpus=1, service=None),
diff --git a/nova/tests/scheduler/test_filter_scheduler.py b/nova/tests/scheduler/test_filter_scheduler.py
index b6bdd359b..be6bc3317 100644
--- a/nova/tests/scheduler/test_filter_scheduler.py
+++ b/nova/tests/scheduler/test_filter_scheduler.py
@@ -224,7 +224,7 @@ class FilterSchedulerTestCase(test_scheduler.SchedulerTestCase):
         hostinfo.update_from_compute_node(dict(memory_mb=1000,
                 local_gb=0, vcpus=1, disk_available_least=1000,
                 free_disk_mb=1000, free_ram_mb=872, vcpus_used=0,
-                local_gb_used=0))
+                local_gb_used=0, updated_at=None))
         self.assertEquals(872, fn(hostinfo, {}))
 
     def test_max_attempts(self):
diff --git a/nova/tests/scheduler/test_host_manager.py b/nova/tests/scheduler/test_host_manager.py
index 5074d188a..74c24d56b 100644
--- a/nova/tests/scheduler/test_host_manager.py
+++ b/nova/tests/scheduler/test_host_manager.py
@@ -264,7 +264,8 @@ class HostStateTestCase(test.TestCase):
             dict(key='io_workload', value='42'),
         ]
         compute = dict(stats=stats, memory_mb=0, free_disk_gb=0, local_gb=0,
-                       local_gb_used=0, free_ram_mb=0, vcpus=0, vcpus_used=0)
+                       local_gb_used=0, free_ram_mb=0, vcpus=0, vcpus_used=0,
+                       updated_at=None)
 
         host = host_manager.HostState("fakehost", "faketopic")
         host.update_from_compute_node(compute)