Impact of new storage technologies on an OLTP DBMS, its architecture and algorithms.

Abstract

New developments in hardware storage technology introduce fundamentally different performance characteristics and device properties. Storage technologies such as Flash and Non Volatile Memories (NVMs) are asymmetric in terms of their read and write performance, they read much faster than they write. Modern DBMSs are not aware of the underlying asymmetric storage technologies. They are well-developed systems and in principle capable of working with asymmetric storage technologies as a mere replacement, yet they fail to exploit their key properties. Huge performance potential is lying idle and durability of the storage media is shortened which ultimately leads to higher costs. This work is a remedy for those shortcomings, making the DBMS aware of the underlying asymmetric Flash storage and questioning existing multi-version DBMS (MV-DBMS) architecture, algorithms and optimizations. We exploit the performance potential of the asymmetric Flash storage and increase its durability. A re-evaluation and redesign of components within the DBMS is necessary, inevitably leading to a redesign of the whole DBMS. Without such a redesign, the DBMS software stack will become the new I/O bottleneck. The combination of the MV-DBMS, multi-versioning concurrency control (MVCC) and append/log-based storage management (LbSM) on Flash storage delivers optimal performance figures which are needed to satisfy the urgent demand in scalable performance for modern DBMSs