Hi, in current codebase, myfaces use mostly enhanced loop for iterating over chidren:
for (UIComponent child: getChildren()) that creates new instance of iterator. After change to plain old indices: for (i = 0; i < childCount; i++) child = getChildren().get(i); I achieved following results in my test case: 1) number of AbstractList$Itr from ~ 100 000 down to ~1500 instances per one render/response 2) time for one render/response from ~1500ms down to ~900ms please see https://issues.apache.org/jira/browse/MYFACES-3130 for more details. We know that getChildren() is type of ArrayList (javax.faces.component._ComponentChildrenList) - in this situation is index-based loop safe change. But custom component can override implementation of getChildren() and provide own implementation which can be slower: I know about Trinidad: uses ArrayList too, so no risk here (org.apache.myfaces.trinidad.component.ChildArrayList) I use RichFaces and PrimeFaces too and don't see custom implementation of children in their codebase. What do you think about this problem? The performance gain is pretty big but also risky. Regards, Kočičák
