Removing the Costs of Indirection in Flash-based SSDs with Nameless Writes

We present nameless writes, a new interface that obviates the need for indirection in modern solid-state storage devices (SSDs). Nameless writes allow the device to pick the location of a write and only then inform the client above of the decision. Doing so keeps control of block allocation decisions in the device, thus enabling it to perform important tasks such as wear-leveling, while removing the need for large and costly indirection tables. We discuss the proposed interface as well as the requisite device and file-system support.