Managing a computing cluster using durability level indicators

A method for managing data in a distributed data processing system including a number of processing nodes includes storing data units in data stores that are associated with a number of different levels of durability. The method includes maintaining indicators including a first indicator associated with a first durability level and a second indicator associated with a second durability level. The first indicator is maintained to reflect a time interval at which all sets of data units associated with the time interval are stored at the first durability level. The second indicator is maintained to reflect a timer interval at which all sets of data units associated with the time interval are stored at the second durability level. The first and second indicators are used to manage processing of the data units in the distributed data processing system.