基於當前存取集合之超大容量快閃記憶體位址投射

Abstract

隨著儲存裝置容量的快速成長，設計快閃記憶體管理層之位址投射機制已儼然形成一個艱鉅的挑戰。不同於以往的設計，我們提出了一個和儲存裝置容量無關、但基於使用者之當前存取集合（稱為 working-set）來設計的位置投射機制。這個機制顯著地提升了系統效能並達到了小單位位址投射機制的存取速率。此外，我們也提出了一個簡單且可實施的方式來平均地使用快閃記憶體，並同時能提供快閃記憶體壽命估測之能力。最後，藉由一系列之實驗，我們驗證了所提出方法之有效性，並得到了令人振奮的結果。

Address mapping for flash devices has been a challenging design problem for controllers because of the rapidly growing device capacity. Different from the past work, a capacity-independent address mapping scheme that only depends on users' access data set, referred to as working set, is proposed. As a result, fine-grained address mapping is achieved with significant performance boosting, compared to the past work. In addition, a simple but practical wear-leveling design is proposed with the capability in lifetime estimation of flash devices. The proposed scheme was evaluated by a series of experiments with encouraging results.