Remove resource used fields from ComputeNode

The node resource(vcpu, memory and disk) used infomation need
to change when creating or deleting instances. Now Placement do
not send notifications, so there is not a good way to capture
the change. We remove these fields and leave the process to strategy.

Partially Implements: blueprint improve-compute-data-model

Change-Id: I3f9a3279a26f3df444117d9265e74cca57b38d6e

watcher/decision_engine/model/collector/nova.py

@@ -341,23 +341,6 @@ class NovaModelBuilder(base.BaseModelBuilder):
             disk_gb_reserved = 0
             disk_ratio = 1.0
 
-        usages = self.placement_helper.get_usages_for_resource_provider(
-            node.id)
-        if usages and orc.VCPU in usages:
-            vcpus_used = usages[orc.VCPU]
-        else:
-            vcpus_used = node.vcpus_used
-
-        if usages and orc.MEMORY_MB in usages:
-            memory_used = usages[orc.MEMORY_MB]
-        else:
-            memory_used = node.memory_mb_used
-
-        if usages and orc.DISK_GB in usages:
-            disk_used = usages[orc.DISK_GB]
-        else:
-            disk_used = node.local_gb_used
-
         # build up the compute node.
         node_attributes = {
             # The id of the hypervisor as a UUID from version 2.53.
@@ -366,7 +349,6 @@ class NovaModelBuilder(base.BaseModelBuilder):
             "memory": memory_mb,
             "memory_ratio": memory_ratio,
             "memory_mb_reserved": memory_mb_reserved,
-            "memory_mb_used": memory_used,
             # The node.free_disk_gb does not take allocation ratios used
             # for overcommit into account so this value may be negative.
             # We do not need this field and plan to set disk to total disk
@@ -374,13 +356,11 @@ class NovaModelBuilder(base.BaseModelBuilder):
             "disk": disk_capacity,
             # TODO(licanwei): remove and replace by disk field
             "disk_capacity": disk_capacity,
-            "disk_gb_used": disk_used,
             "disk_gb_reserved": disk_gb_reserved,
             "disk_ratio": disk_ratio,
             "vcpus": vcpus,
             "vcpu_reserved": vcpu_reserved,
             "vcpu_ratio": vcpu_ratio,
-            "vcpus_used": vcpus_used,
             "state": node.state,
             "status": node.status,
             "disabled_reason": node.service["disabled_reason"]}