The International Conference for High Performance Computing, Networking, Storage and Analysis
WrAP: Write Aside Persistence for Storage Class Memory in High Performance Computing.
Student: Ellis Giles (Rice University)
Supervisor: Peter Varman (Rice University)
Abstract: Emerging memory technologies like Phase Change Memory or Memristors (generically called SCM or Storage Class Memory) combine the ability to access data at byte granularity with the persistence of storage devices like hard disks or SSDs. By accessing data directly from SCM addresses instead of slow block I/O operations, developers can gain 1-2 orders of performance. However, this pushes upon developers the burden of ensuring that SCM stores are ordered correctly, flushed from processor caches, and if interrupted by sudden machine stoppage, do not leave objects in SCM in inconsistent states.
Software based Write Aside Persistence, or WrAP, provides durability and consistency for SCM writes, while ensuring fast paths to data in caches, DRAM, and persistent memory tiers. Simulations such as the Graph 500 Benchmark indicate significant performance gains over traditional log based approaches.