Efficient Sanitization Design for LSM-based Key-Value Store over 3D MLC NAND Flash

Abstract

Conventional LSM tree designs delete data by inserting a delete mark to the specified key, and they thus it leaves several out-of-date values to the specified key on the LSM tree. As a result, the LSM tree encounters a serious data security issue due to the undeleted values when there arises the need for data sanitization. Sanitization is a time-consuming process that involves completely removing sensitive data from storage devices. Flash-based SSDs are widely used in many systems, but they lack an in-place update feature, which makes it difficult for LSM trees to maintain both privacy and performance on these devices. This work proposes an efficient sanitizable LSM-tree design for LSM-based key-value store over 3D NAND flash memories. Our proposed efficient sanitizable LSM-tree design focuses on integrating the processes of key-value pair updating and the execution of sanitization by exploiting our proposed influence-conscious programming method. The capability of the proposed design is evaluated by a series of experiments, for which we have very encouraging results.