Performance tweaking and benchmarks.

1 files changed, 40 insertions, 7 deletions

diff --git a/cobbler/serializer.py b/cobbler/serializer.py
index 8593aad..ae9f18c 100644
--- a/cobbler/serializer.py
+++ b/cobbler/serializer.py
@@ -16,52 +16,82 @@ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 import errno
 import os
 from rhpl.translate import _, N_, textdomain, utf8
+import fcntl
 
 from cexceptions import *
 import utils
 import api as cobbler_api
 
+LOCK_ENABLED = True
+LOCK_HANDLE = None
+
+def __grab_lock():
+   if not LOCK_ENABLED:
+       return
+   if not os.path.exists("/var/lib/cobbler/lock"):
+       fd = open("/var/lib/cobbler/lock","w+")
+       fd.close()
+   LOCK_HANDLE = open("/var/lib/cobbler/lock","r")
+   fcntl.flock(LOCK_HANDLE.fileno(), fcntl.LOCK_EX)
+
+def __release_lock():
+   if not LOCK_ENABLED:
+       return
+   LOCK_HANDLE = open("/var/lib/cobbler/lock","r")
+   fcntl.flock(LOCK_HANDLE.fileno(), fcntl.LOCK_UN)
+   LOCK_HANDLE.close()
+
 def serialize(obj):
     """
     Save a collection to disk or other storage.  
     """
+    __grab_lock()
     storage_module = __get_storage_module(obj.collection_type())
     storage_module.serialize(obj)
+    __release_lock()
     return True
 
 def serialize_item(collection, item):
     """
     Save an item.
     """
+    __grab_lock()
     storage_module = __get_storage_module(collection.collection_type())
     save_fn = getattr(storage_module, "serialize_item", None)
     if save_fn is None:
         # print "DEBUG: WARNING: full serializer"
-        return storage_module.serialize(collection)
+        rc = storage_module.serialize(collection)
     else:
         # print "DEBUG: partial serializer"
-        return save_fn(collection,item)
+        rc = save_fn(collection,item)
+    __release_lock()
+    return rc
 
 def serialize_delete(collection, item):
     """
     Delete an object from a saved state.
     """
+    __grab_lock()
     storage_module = __get_storage_module(collection.collection_type())
     delete_fn = getattr(storage_module, "serialize_delete", None)
     if delete_fn is None:
         # print "DEBUG: full delete"
-        return storage_module.serialize(collection)
+        rc = storage_module.serialize(collection)
     else:
         # print "DEBUG: partial delete"
-        return delete_fn(collection,item)
-    
+        rc = delete_fn(collection,item)
+    __release_lock()
+    return rc
 
 def deserialize(obj,topological=False):
     """
     Fill in an empty collection from disk or other storage
     """
+    __grab_lock()
     storage_module = __get_storage_module(obj.collection_type())
-    return storage_module.deserialize(obj,topological)
+    rc = storage_module.deserialize(obj,topological)
+    __release_lock()
+    return rc
 
 def deserialize_raw(collection_type):
     """
@@ -69,8 +99,11 @@ def deserialize_raw(collection_type):
     disk state, without going through the Cobbler object system.
     Much faster, when you don't need the objects.
     """
+    __grab_lock()
     storage_module = __get_storage_module(collection_type)
-    return storage_module.deserialize_raw(collection_type)
+    rc = storage_module.deserialize_raw(collection_type)
+    __release_lock()
+    return rc
 
 def __get_storage_module(collection_type):
     """