Merge "Yield to another greenthread when some time-consuming task fin…

…ished."

nova/manager.py

@@ -53,6 +53,8 @@
 
 """
 
+import eventlet
+
 from nova.db import base
 from nova import flags
 from nova.openstack.common import log as logging
@@ -171,6 +173,9 @@ def periodic_tasks(self, context, raise_on_error=False):
 
             try:
                 task(self, context)
+                # NOTE(tiantian): After finished a task, allow manager to
+                # do other work (report_state, processing AMPQ request etc.)
+                eventlet.sleep(0)
             except Exception as e:
                 if raise_on_error:
                     raise

nova/virt/libvirt/driver.py

@@ -1996,6 +1996,8 @@ def get_vcpu_used(self):
                 total += 1
             else:
                 total += len(vcpus[1])
+            # NOTE(gtt116): give change to do other task.
+            greenthread.sleep(0)
         return total
 
     def get_memory_mb_used(self):
@@ -2690,7 +2692,8 @@ def get_disk_available_least(self):
             except exception.InstanceNotFound:
                 # Instance was deleted during the check so ignore it
                 pass
-
+            # NOTE(gtt116): give change to do other task.
+            greenthread.sleep(0)
         # Disk available least size
         available_least_size = dk_sz_gb * (1024 ** 3) - instances_sz
         return (available_least_size / 1024 / 1024 / 1024)