[ISCA09] PCM for main memory (DAc'o9j CCD’11 [CIDR'1 CPU CPU CPU L1/L2 Cache L1/L2 Cache L1/L2 Cache Memory Controller Memory Controller Memory Controller DRAM Cache Write buffer Phase Change Memory Phase Change Memory Phase Change Memory HDD/SSD Disk HDD/SSD Disk HDD/SSD Disk (a PCM-only memory (b DRAM as a cache memory cDRAM as a write bufferPCM for main memory Phase Change Memory Memory Controller HDD/SSD Disk CPU L1/L2 Cache (a)PCM-only memory Phase Change Memory Memory Controller HDD/SSD Disk CPU L1/L2 Cache DRAM Cache (b)DRAM as a cache memory Phase Change Memory Memory Controller HDD/SSD Disk CPU L1/L2 Cache DRAM Write buffer (c)DRAM as a write buffer [ISCA’09] [ICCD’11] [DAC’09] [CIDR’11]