Accelerating Cloud Storage System with Byte-Addressable Non-Volatile Memory

摘要

As building block for cloud storage, distributed file system uses underlying local file systems to manage objects. However, the underlying file system, which is limited by metadata and journaling I/O, significantly affects the performance of the distributed file system. This paper presents an NVM-based file system (referred to as NV-Booster) to accelerate object access for storage node. The NV-Booster leverages byte-addressability and persistency of nonvolatile memory (NVM) to speedup metadata accesses and file system journaling. With NV-Booster, metadata is kept in NVM and accessed in byte-addressable manner through memory bus, while object is stored on hard disk and accessed from I/O bus. In addition, proposed NV-Booster enables fast object search and mapping between object ID and on-disk location with an efficient in-memory namespace management. NV-Booster is implemented in kernel space with NVDIMM and has been extensively evaluated under various workloads. Our experiments show that NV-Booster improves Ceph performance up to 10X, compared to the Ceph with existing local file systems.