1,721,222 research outputs found
Behavior investigation of concurrent Java programs: an approach based on source-code instrumentation
No full textJava makes easier the coding phase of concurrent applications and provides friendly mechanisms for the information exchange among threads and different processes. The nature of communication and synchronization mechanisms and the actual parallelism of a distributed environment introduce potential sources of non-deterministic behavior in concurrent applications. In order to investigate on undesired effects related to non-deterministic behaviors, tracing and replay capabilities can be added to the programming environment. Such capabilities are useful for testing, debugging, monitoring, performance evaluation and program profiling purposes. This paper presents a solution for providing tracing and replay capabilities to a number of Java concurrent applications. Such a solution addresses portability and it is based on the automatic instrumentation of the original source code. Some transformation schemes have been applied to some classes in the standard Java packages in order to make easier and more efficient the automatic instrumentation task. It is shown how the object-oriented structure of Java can be exploited in a deep and efficient way both in the instrumentation and in the tracing and replay phases. (C) 2001 Elsevier Science B.V. All rights reserved
Optimizing the Instruction Cache Performance of Embedded Systems
No full textIn the embedded domain, the gap between memory and processor performance and the increase in application complexity need to be supported without wasting precious system resources: die size, power, etc. For these reasons, effective exploitation of small and simple cache memories is of the utmost importance. However, programs running on such caches can experience serious inefficiencies due to cache conflicts.We present a new Cache-Aware Code Allocation Technique (CAT), which transforms the structure of programs so that their behavior toward memory can meet the locality features the cache is able to exploit. The proposed approach uses detailed information of program execution to place program areas into memory and employs the new idea of “look-forward estimation” that helps to seek better global layouts during the placement of each area. CAT-optimized programs outperform the original ones achieving the same miss rate on two times, and sometimes four times, smaller caches. Moreover, CAT improves the instruction miss rate by more than 40% if compared to the best procedure-reordering algorithm. CAT performances derive from the increased number of cache lines that support the execution of optimized applications and from a more balanced load on them
DISDEB: an interactive high-level debugging system for a multi-microprocessor system
No full textThis paper describes the architecture of the interactive debugging system DISDEB, which is intended to debug programs on a multi-microprocessor system constituting a node of the Selenia Mara architecture. DISDEB requires neither changes in or additions to the code produced by the compiler nor heavy modifications to the operating system Kernel. Moreover, the use of ad hoc hardware provided with autonomous processing power allows the user to monitor and control the execution of both concurrent and distributed processes and their interactions, while, in most cases, maintaining the real-time operation of the target Mara system
Instrumentation of Concurrent Java Applications for Program Behavior Investigation
No full textJava makes easier the coding phase of concurrent applications and provides friendly mechanisms for the information exchange among threads and different processes. The nature of communication and synchronization mechanisms and the actual parallelism of a distributed environment introduce potential sources of non-deterministic behavior in concurrent applications. In order to investigate on undesired effects related to non-deterministic behaviors, tracing and replay capabilities can be added to the programming environment. Such capabilities are useful for testing, debugging, monitoring and performance evaluation purposes. This paper presents a solution for providing tracing and replay capabilities to Java concurrent applications. Such a solution addresses portability and it is based on the automatic instrumentation of the original source code. Some transformation schemes have been applied to some classes in the standard Java packages in order to make easier and more efficient the automatic instrumentation task. It is shown how the object-oriented structure of Java can be exploited in a deep and efficient way both in the instrumentation and in the tracing and replay phases
Hipeac Network of Excellence N. IST-004408 Deliverable D3.b - Report on Research Results. Cluster 1150 - Adaptable Computers for Embedded Applications
No full text- …
