Extract from [Felix Wiedemann]
This storage stack uses multiple layers to reduce the complexity of the design and to simplify the reasoning for each component (see Figure 3.1). Many concepts shown in this chapter are heavily based on ZFS which will be presented in detail later on in Section 4.2.
At the bottom of the storage stack, we have the Vdev Layer (short for virtual device) and the Storage Pool Layer (SPL).
SMASH is a research project that is investigating the benefits of a common storage engine that manages a heterogeneous storage landscape, including traditional storage devices and non-volatile memory technologies. The core of this storage engine will be Bϵ-trees, which can be used to efficiently exploit these different devices. Furthermore, data placement and migration strategies will be investigated to minimize the overhead caused by transferring data between different devices. Eliminating the need for volatile caches will allow data consistency guarantees to be improved.