The performance and power benefits of Flash memory have paved its adoption in mass storage devices in the form of Solid-State Disks (SSDs). Despite these benefits, Flash memory's limited write endurance remains a big impediment to its wide adoption in the enterprise server market. Existing research efforts have mostly focused on proposing various mechanisms and algorithms to improve SSD's performance and reliability. However, there is still a lack of flexible tools that allow characterizing SSD endurance (i.e., wear-out behavior) and investigating its impact on applications without affecting the lifetime of the real SSD device. To address this issue,  SolidSim , a kernel-level simulator has been enhanced with capabilities to simulate state-of-the-art wear-leveling, garbage-collection and other advanced internal management techniques of an SSD. These extensions have further increased SolidSim's flexibility to study both SSD performance and endurance characteristics. Our approach allows investigating these characteristics without requiring any changes to applications or gathering any workload traces. The paper presents insights into wear-out behavior including logical, physical and translation characteristics, and correlates them with application behavior and SSD life-times using a set of representative workloads.
['Gokul B. Kandiraju', 'Kaoutar El Maghraoui']
A flexible OS-based approach for characterizing solid-state disk endurance