A suffix tree is a fundamental data structure for string searching algorithms. Unfortunately, when it comes to the use of suffix trees in real-life applications, the current methods for constructing suffix trees do not scale for large inputs. As suffix trees are larger than the input sequences and quickly outgrow the main memory, the first attempts at building large suffix trees focused on algo...

The demand for real-time database services has been increasing recently. Examples include sensor data fusion, stock trading, decision support, web information services, and data-intensive smart spaces. In these systems, it is essential to execute transactions in time using fresh (temporally consistent) data. Due to the high service demand, many transactions may miss their deadlines regardless o...

In moving object databases, existing disk-based indexes are unable to keep up with the high update rate while providing speedy retrieval at the same time. However, efficient management of moving-object database can be achieved through aggressive use of main memory. In this paper, we propose an Integrated Memory Partitioning and Activity Conscious Twin-index (IMPACT) framework where the moving o...

The ever increasing amount of linked open data results in a demand for high performance graph databases. In this paper we therefore introduce a memory layout which is tailored to the storage of large RDF data sets in main memory. We present the memory layout SpiderStore. This layout features a node centric design which is in contrast to the prevailing systems using triple focused approaches. Th...

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In the field of disk-based parallel database management systems exists a great variety of solutions based on a shared-storage or a shared-nothing architecture. In contrast, main memory-based parallel database management systems are dominated solely by the shared-nothing approach as it preserves the in-memory performance advantage by processing data locally on each server. We argue that this uni...

The objective of this paper is to develop a high performance hash-based access method for main memory database systems. Chained bucket hashing is known to provide the fastest random access to a static file stored in main memory. For a dynamic file, however, chained bucket hashing is inappropriate because its address space cannot be adapted to the file size without total reorganization. Extendib...

Optimal search in main memory databases requires at most one key comparison to locate a record. Extendible hashing becomes impractical when it is adapted to yield optimal search in main memory databases because of its large directory size. Multi-directory hashing techniques can provide significantly improved directory utilization over extendible hashing. The objective of this paper is to analyz...

Energy is becoming a critical resource to not only small battery-powered devices but also large server systems, where high energy consumption translates to excessive heat dissipation, which, in turn, increases cooling costs and causes servers to become more prone to failure. Main memory is one of the most energy-consuming components in many systems. In this paper, we propose and evaluate a nove...

A growing part of the energy, battery-driven embedded system, is consumed by the off-chip main memory. In order to minimize this memory consumption, an architectural solution is recently adopted. It consists of multi-banking the addressing space instead of monolithic memory. The main advantage in this approach is the capability of setting banks in low power modes when they are not accessed, suc...