In this paper we address the problem of dynamic memory management in real-time Java embeddedsystems. Our work aims at suppressing the need for garbage collection in order to avoid unpredictable pause times. For that ...
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ISBN:
(纸本)9780769529752
In this paper we address the problem of dynamic memory management in real-time Java embeddedsystems. Our work aims at suppressing the need for garbage collection in order to avoid unpredictable pause times. For that we use a simple static analysis algorithm coupled with region-based memory management as presented in [151] To overcome the well-known limitations of region inference, we propose in this paper to involve the developer in the analysis process by providing feedback on programming constructs likely to produce memory leaks. Experiments show that for most programming patterns, our system behaves as efficiently as a garbage collector in terms of memory consumption. Our analysis tool is furthermore able to provide useful feedback to the programmer to pinpoint problematic constructs.
In network-enabled consumer electronics development, much of the time and effort is spent analyzing and solving network performance problems. In this paper, we define an instance of such problems discovered while deve...
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ISBN:
(纸本)9780769529752
In network-enabled consumer electronics development, much of the time and effort is spent analyzing and solving network performance problems. In this paper, we define an instance of such problems discovered while developing a commercial home network gateway. We then analyze its cause and propose a solution mechanism. Our home network gateway uses an asymmetric link (ADSL) and suffers from an undesirable phenomenon where downlink traffic interferes with upload speed. We call this phenomenon the network performance interference problem. While this problem can easily be confused with receive livelock caused by packet contention at the input queue, we find that this is not the case. By performing extensive experiments and analysis, we reveal that our problem is caused by packet contention at the output queue and certain intrinsic characteristics of TCP. We devise an ACK-separation queuing mechanism for this problem and implement it in the home network gateway. Our experiments show that it effectively solves the problem.
We consider a resource synthesis technique for real-timesystems where dynamic voltage scaling is supported, the energy budget is limited, and the performance of the system depends on how resources and energy are used...
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ISBN:
(纸本)9780769529752
We consider a resource synthesis technique for real-timesystems where dynamic voltage scaling is supported, the energy budget is limited, and the performance of the system depends on how resources and energy are used We propose a resource synthesis technique that derives boththe supply voltages and the resource allocation of the tasks in the system to maximize system performance. the resulting system satisfies real-time schedulability and energy requirements.
Two architectural paradigms for the development of hierarchical systems arguably stand out for their flexibility and ease of reconfiguration: the server-based architecture and the priority-band architecture. Whilst th...
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ISBN:
(纸本)9780769529752
Two architectural paradigms for the development of hierarchical systems arguably stand out for their flexibility and ease of reconfiguration: the server-based architecture and the priority-band architecture. Whilst the former has been deeply investigated, the latter, a fresh addition to a mainstream programming language standard, still lacks an accurate study of its timing behaviour In this paper we relate those two architectural paradigms and devise timing analysis equations for the priority-band systems off the solid roots of the server-based theory.
the paper presents a time-triggered distributed object computing environment for embedded control systems such as automotive control systems. the time-triggered architecture is suitable for hard real-timesystems. We ...
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ISBN:
(纸本)9780769529752
the paper presents a time-triggered distributed object computing environment for embedded control systems such as automotive control systems. the time-triggered architecture is suitable for hard real-timesystems. We present a time-triggered distributed object model as an extension to the time-triggered object model that consists of objects periodically updating their own attribute values. the model is suitable for embedded control systems in which the control logics are designed with control block diagrams. Replica objects are used for efficient location transparency in the model and inter-object communications are local method calls, not remote method invocations. We have developed a distributed computing environment based on the time-triggered distributed object model. the middleware maintains the replicas to be consistent withthe original objects using periodic state messages. the middleware executes the replication processing withthe stubs that bridge the original objects, the middleware, and the replicas. We have also developed a development environment for embedded control application programs based on the time-triggered distributed object model. the stubs are generated from the interface definitions written in CORBA-compliant IDL.
In this paper we analyze the influence of the urgency in the timed transitions, and as consequence, in the test suite generation. As result, we formalize rules to generate sequences where the messages exchanged may be...
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ISBN:
(纸本)9780769529752
In this paper we analyze the influence of the urgency in the timed transitions, and as consequence, in the test suite generation. As result, we formalize rules to generate sequences where the messages exchanged may be instantaneous or delayed. In addition, the generated scenarios are able to detect timing faults. For test generation, we use a prototype tool called HJ2IF It is based on a test purpose algorithm, called Hit-or-Jump and it is applied for systems specified using Intermediate Format language (IF).
this paper attempts to analyze the boot-up time of bootloader and Linux Kernel. and to compare performance of several root file-systems for fast boot-up time in the embedded Linux. therefore, it was implemented with t...
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ISBN:
(纸本)9780769529752
this paper attempts to analyze the boot-up time of bootloader and Linux Kernel. and to compare performance of several root file-systems for fast boot-up time in the embedded Linux. therefore, it was implemented withtime measurement module to analyze the boot-up time of bootloader and Linux kernel, and measured the time at each event point related to boot-up. As a result of analysis of six cases packaging, it has turned out the fact that the data checksum routine, decompressing the kernel and ramdisk image takes most of the boot-up time. Root file-system was packaged through analyzing such performance as boot-up time, memory usage, file system size. this is based on raw-kernel image and a combination of CRAMFS and JFFS2, and it has small size of the root file-system, the boot-up time is decreased.
Remote health monitoring affords the possibility of improving the quality of health care by enabling relatively inexpensive out-patient care. However, remote health monitoring raises new a problem: the potential for d...
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ISBN:
(纸本)9780769529752
Remote health monitoring affords the possibility of improving the quality of health care by enabling relatively inexpensive out-patient care. However, remote health monitoring raises new a problem: the potential for data explosion in health care systems. To address this problem, the remote health monitoring systems must be integrated with analysis tools that provide automated trend analysis and event detection in realtime. In this paper, we propose an overview of Century, an extensible framework for analysis of large numbers of remote sensor-based medical data streams.
Code optimization of the offset assignment generated in embeddedsystems allows for power and space efficient systems. We propose a new heuristic that uses edge classification to commutatively transformation and optim...
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ISBN:
(纸本)9780769529752
Code optimization of the offset assignment generated in embeddedsystems allows for power and space efficient systems. We propose a new heuristic that uses edge classification to commutatively transformation and optimize the assignment. We introduce concept of breakable and unbreakable edges, which assists in selecting edges for path cover and edges for commutative transformation.
the message scheduling is an essential mechanism in the context of Nerworked Control systems (NCS) which are systems based on communication networks and which allow, in particular the implementation of closed loop dis...
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ISBN:
(纸本)9780769529752
the message scheduling is an essential mechanism in the context of Nerworked Control systems (NCS) which are systems based on communication networks and which allow, in particular the implementation of closed loop distributed control applications. the scheduling of the messages of the flows of these closed loop distributed applications strongly influences the stability of these applications. the message scheduling is, in several networks, mainly based on fixed (static) priorities associated to the messages (for example the network CAN). In previous works, we have shown that the static priority scheme has intrinsic limitations and so, we propose in this paper in order to overcome these limitations, the concept of hybrid (hierarchical) priority. Different hybrid priority schemes are presented and evaluated with respect to the stability performances of the closed loop distributed process control applications. We show, in particular the advantage of a scheduling based on a scheme "hybrid priority + time strategy".
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