Fixed performance issue in list_permitted_lpars/partitions()

Details:

* In zhmcclient version 1.13.0, an optimization was added where list() and
  find_local() were now utilizing the name-to-URI cache when only the
  resource name was specified as a filter argument.
  The Console.list_permitted_lpars/partitions() methods used find_local() to
  look up the parent CPC of the returned LPARs/partitions and specified
  'se-version' as an additional property. However, find_local() uses the
  additional properties only when the resource object was not found in the
  name-to-URI cache. Because of the optimization, the Cpc object was now
  found in the cache, and the 'se-version' property was therefore not
  added anymore.

  The performance degradation was fixed by (1) creating local resource
  objects for the parent CPCs Console.list_permitted_lpars/partitions()
  in order to have better control over the properties they have, and (2) by
  reducing the Cpc objects to one for each real CPC (before we created one
  Cpc object for each Lpar/Partition object.

Signed-off-by: Andreas Maier <maiera@de.ibm.com>

docs/changes.rst

@@ -77,6 +77,17 @@ Released: not yet
 
 * Development: Fixed dependency issue with safety 3.0.0 by pinning it.
 
+* Performance: In zhmcclient version 1.13.0, an optimization was added where
+  list() and find_local() were now utilizing the name-to-URI cache when only the
+  resource name was specified as a filter argument. This caused the 'se-version'
+  property to no longer be in the local zhmcclient.Cpc objects that were used
+  as the parent objects of the Lpar/Partition objects returned by
+  Console.list_permitted_lpars/partitions() and caused a performance
+  degradation in the zhmc_lpar_list and zhmc_partition_list Ansible modules due
+  to repeated "Get CPC Properties" operations for retrieving the 'se-version'
+  property. This was fixed in the Console.list_permitted_lpars/partitions()
+  methods.
+
 **Enhancements:**
 
 * Test: Added Python 3.8 with latest package levels to normal tests because

zhmcclient/_console.py

@@ -670,8 +670,10 @@ def list_permitted_partitions(
             self.uri, query_parms_str)
         result = self.manager.session.get(uri, resource=self)
 
+        cpcs_by_uri = {}  # caches local Cpc objects for CPCs already seen
         partition_objs = []
         if result:
+            cpc_manager = self.manager.client.cpcs
             partition_items = result['partitions']
             for partition_item in partition_items:
 
@@ -682,18 +684,21 @@ def list_permitted_partitions(
                 # * cpc-object-uri (CPC property 'object-uri')
                 # * se-version (CPC property 'se-version') (if >=2.14.1)
 
-                # Create a 'skeleton' local Cpc object we can hang the
-                # Partition objects off of, even if the user does not have
-                # access permissions to these CPCs. Note that different
-                # partitions can have different parent CPCs.
-                cpc_props = {}
-                if 'se-version' in partition_item:
-                    cpc_props['se-version'] = partition_item['se-version']
-                cpc = self.manager.client.cpcs.find_local(
-                    partition_item['cpc-name'],
-                    partition_item['cpc-object-uri'],
-                    cpc_props,
-                )
+                cpc_uri = partition_item['cpc-object-uri']
+                try:
+                    cpc = cpcs_by_uri[cpc_uri]
+                except KeyError:
+                    # Create a 'skeleton' local Cpc object we can hang the
+                    # Partition objects off of, even if the user does not have
+                    # access permissions to these CPCs. Note that different
+                    # partitions can have different parent CPCs.
+                    cpc_props = {}
+                    cpc_props['name'] = partition_item['cpc-name']
+                    if 'se-version' in partition_item:
+                        cpc_props['se-version'] = partition_item['se-version']
+                    cpc = cpc_manager.resource_object(cpc_uri, cpc_props)
+
+                    cpcs_by_uri[cpc_uri] = cpc
 
                 partition_obj = cpc.partitions.resource_object(
                     partition_item['object-uri'],
@@ -798,8 +803,10 @@ def list_permitted_lpars(
             self.uri, query_parms_str)
         result = self.manager.session.get(uri, resource=self)
 
+        cpcs_by_uri = {}  # caches local Cpc objects for CPCs already seen
         lpar_objs = []
         if result:
+            cpc_manager = self.manager.client.cpcs
             lpar_items = result['logical-partitions']
             for lpar_item in lpar_items:
 
@@ -811,18 +818,21 @@ def list_permitted_lpars(
                 # * cpc-object-uri (CPC property 'object-uri')
                 # * se-version (CPC property 'se-version') (if >=2.14.1)
 
-                # Create a 'skeleton' local Cpc object we can hang the
-                # Partition objects off of, even if the user does not have
-                # access permissions to these CPCs. Note that different
-                # partitions can have different parent CPCs.
-                cpc_props = {}
-                if 'se-version' in lpar_item:
-                    cpc_props['se-version'] = lpar_item['se-version']
-                cpc = self.manager.client.cpcs.find_local(
-                    lpar_item['cpc-name'],
-                    lpar_item['cpc-object-uri'],
-                    cpc_props,
-                )
+                cpc_uri = lpar_item['cpc-object-uri']
+                try:
+                    cpc = cpcs_by_uri[cpc_uri]
+                except KeyError:
+                    # Create a 'skeleton' local Cpc object we can hang the
+                    # Partition objects off of, even if the user does not have
+                    # access permissions to these CPCs. Note that different
+                    # partitions can have different parent CPCs.
+                    cpc_props = {}
+                    cpc_props['name'] = lpar_item['cpc-name']
+                    if 'se-version' in lpar_item:
+                        cpc_props['se-version'] = lpar_item['se-version']
+                    cpc = cpc_manager.resource_object(cpc_uri, cpc_props)
+
+                    cpcs_by_uri[cpc_uri] = cpc
 
                 lpar_props = {
                     'name': lpar_item['name'],
@@ -970,13 +980,13 @@ def list_permitted_adapters(
 
             # Group the returned adapters by CPC
             adapter_items_by_cpc = {}
-            cpcs_by_cpc = {}
+            cpcs_by_name = {}
             for adapter_item in result['adapters']:
                 cpc_name = adapter_item['cpc-name']
                 if cpc_name not in adapter_items_by_cpc:
                     adapter_items_by_cpc[cpc_name] = []
                 adapter_items_by_cpc[cpc_name].append(adapter_item)
-                if cpc_name not in cpcs_by_cpc:
+                if cpc_name not in cpcs_by_name:
                     # Create a 'skeleton' local Cpc object we can hang the
                     # Adapter objects off of, even if the user does not have
                     # access permissions to these CPCs. Note that different
@@ -991,10 +1001,10 @@ def list_permitted_adapters(
                         uri=adapter_item['cpc-object-uri'],
                         properties=cpc_props,
                     )
-                    cpcs_by_cpc[cpc_name] = cpc
+                    cpcs_by_name[cpc_name] = cpc
 
             # Process the returned adapters
-            for cpc_name, cpc in cpcs_by_cpc.items():
+            for cpc_name, cpc in cpcs_by_name.items():
                 adapter_items = adapter_items_by_cpc[cpc_name]
                 adapter_manager = cpc.adapters
                 if full_properties: