A method includes providing a collection that includes a plurality of local lists. Each local list is associated with a different processor or thread in a multi-processor system. An interface to the collection is provided for adding elements to and removing elements from the collection. An add operation is performed with a first processor in the multi-processor system using the interface to add a first element to the collection. The interface is configured to cause the first element to be added to the local list associated with the first processor.