Rethinking the Interface to Solid-State Storage

Опубликовано 28 июля 2016, 0:29

Solid-state storage devices such as flash and phase-change memory have dramatically different properties than disks, yet are exposed in many systems as a generic block device. In this talk, I will present two systems that update the interface to such devices to better match their capabilities with their intended use. First, we investigated use of solid-state flash drives (SSDs) as a cache in front of slower disks. We find that there are numerous differences between the interface offered by the device, a persistent block store, and the service it provides, caching data. I will describe a new flash-caching system called FlashTier that redresses these differences through new block-addressing and space-management techniques. I will then discuss our work on storage devices that support direct access by applications. New storage-class memory (SCM) technologies, such as phase-change memory, promise user-level access to non-volatile storage through regular memory instructions. We built Mnemosyne, a simple interface for programming with persistent memory that addresses two challenges: how to create and manage such memory, and how to ensure consistency in the presence of failures.