Computer pioneers correctly predicted that programmers would want unlimited amounts of fast memory. Since fast memory is expensive, an economical solution to that desire is a memory hierarchy organized into several levels. Each level has greater capacity than the preceding but it is less quickly accessible. The goal of the memory hierarchy is to provide a memory system with cost almost as low a...

This tutorial provides an overview of recent developments in mainmemory database systems. With growing memory sizes and memory prices dropping by a factor of 10 every 5 years, data having a “primary home” in memory is now a reality. Main-memory databases eschew many of the traditional architectural tenets of relational database systems that optimized for disk-resident data. Innovative approache...

Recovery activities like logging checkpointing and restart are used to restore a database to a consistent state after a system crash has occurred Recovery related overhead is likely to form a bottleneck in a main memory database since I O activities are performed for the sole purpose of ensuring data durability In this paper we present recovery algorithms which reduce recovery related overheads...

A growing gap between CPU and DRAM performance is driving processors further away from their peak execution rates by increasing the amount of time spent waiting for the memory system. To date, cache memories have been used to good e ect in o setting lagging DRAM speeds by bu ering frequently referenced instructions and data near the CPU. However, continued increases in the cost of DRAM accesses...

This paper describes the VoltDB DBMS as it exists in mid 2013. The focus is on design decisions, especially in concurrency control and high availability, as well as on the application areas where the system has found acceptance. Run-time performance numbers are also included.