The IBM z13 memory subsystem for big data The IBM z13™ system uses the new IBM Centaur memory buffer chip, along with system topology changes, to more than triple system memory capacity (relative to the IBM zEnterprise™ EC12) to 10 TB, and more than triple the drawer-level memory bandwidth to 384 GB/s, and double the DIMM (dual in-line memory module) frequency to 1,600 MHz. The z13 eliminates an asynchronous interface for better store protect key performance. The new memory power save feature on the z13 extends the benefit of the IBM customer power save mode and the IBM cycle steering recovery for lower power. The z13 system builds upon the IBM redundant array of independent memory (RAIM), introduced on the IBM z196 system. New reliability features include single-channel memory bus replay, incremental background lane calibration, and memory scrub hard-error management. An innovative fetch and store tagging architecture, along with a memory quiesce engine, is added to detect RAIM asynchronization events and to re-synchronize memory channels for better performance.