LEVEL-LRU

LEVEL-LRU

Level_0:old lru lists
Level_1:new lru lists

a) insert entry into old-lru list ahead
b) if old-lru size >OMAX,remove last entry from list;then if hits >HIT,move it to new-lru list ahead
c) if new-lru size >NMAX,remove all old-lru entries,move last N entries to old-lru