With　DRAM　memory　systems　power　consumption　growing　and　performance　declining,　memory　system　optimization　is　imperative.　At　present　most　studies　focus　on　reducing　power　consumption　or　improving　performance　of　DRAM　chips,　but　rarely　do　both.　In　this　paper,　we　propose　the　bank　partitioning　based　adaptive　page　policy　to　optimize　both　performance　and　power　efficiency　of　DRAM　chips,　while　at　the　same　time　reduce　the　inter-thread　interference.　First,　we　use　bank　partitioning　to　isolate　memory　streams　of　different　threads.　Second,　we　put　forward　an　adaptive　page　policy　to　dynamically　allocate　the　optimal　page　policy　for　each　bank.　Experimental　results　show　that　our　scheme　improves　the　system　performance　by　20.4%　on　average　(up　to　55%)　and　reduces　DRAM　power　by　8%　on　average　(up　to　29%)　for　all　workloads.