Cache replacement algorithm

When a data is replicated on a site, it is possible that not enough disk/memory space is available. In that case, DAGDA allows to choose a strategy to delete a persistent data. Only a simple persistent data can be deleted, the sticky ones are never deleted by the chosen algorithm. DAGDA offers three algorithm to manage the cache replacement:

• LRU: The least recently used persistent data of sufficient size is deleted.
• LFU: The least frequently used persistent data of sufficient size is deleted.
• FIFO: Among the persistent data of sufficient size, the oldest is deleted.