that large joins can be accelerated almost an order of magnitude on modern RISC hardware when both memory and CPU resources are optimized. Index TermsÐMain-memory databases, query processing, memory access optimization, decomposed storage model, join algorithms, implementation techniques. 1

As main memory grows, query performance is more and more determined by the raw CPU costs of query processing itself. The classical iterator style query processing technique is very simple and flexible, but shows poor performance on modern CPUs due to lack of locality and frequent instruction

for modern hardware. We devised new algorithms and methods to improve all components of database locking, including key range locking, intent locks, detection and recovery from deadlocks, and early lock release. Most of the techniques are easily applicable to other database systems. Experiments with Shore

LLAMA is a subsystem designed for new hardware environments that supports an API for page-oriented access methods, providing both cache and storage management. Caching (CL) and storage (SL) layers use a common mapping table that separates a page’s logical and physical location. CL supports data

applications which cannot harness the available computing power. To prevent the CPU from idling, a multitude of hardware mechanisms and software optimizations have been proposed. Their effectiveness, however, is limited by the sheer volume of data accessed and by the unpredictable sequence of memory requests.

We present a method for determining the worst case execution time (WCET) for programs running on systems with modern hardware architectures, e.g. pipelined processors and cache memory. The method is based on the implicit path enumeration technique (IPET), in which all possible execution paths of a

Abstract. This paper deals with the in uence of hardware aspects of modern computer architectures to the design of software for numerical simulations. We present performance tests for various tasks arising in FEM computations and show under which circumstances performance loss can occur. Further we

structured way details of instruction scheduling needed for performance-enhancing transformations. We show by example how it may be used to make better use of underlying hardware features, including software branch prediction and SIMD instructions. In each case, the use of Multi-Loop transformations allows

. With the introduction of new hardware virtualization extensions, VMI can be further enhanced to provide lightweight, in-band control over the execution of virtual machines. In publica-tions released before the extensions were available, security researchers issued warnings that these new extensions may be used

tures A realtime system is one in which the correctness of the system depends not only on the logical results but also on the time at which the results are produced Hard realtime systems are those where it is absolutely imperative that responses occur within the specied deadlines Examples of areas where realtime systems are used include process control nuclear power plants agile manufacturing intelligent vehicle high way systems avionics air tra c control telecommuni cations the information super highway multimedia realtime simulation virtual reality medical applica tions eg telemedicine and intensive care monitoring and defense applications eg command control and