We propose a parallel distributed memory on-the-fly algorithm for enumerative LTL model checking. The algorithm is designed for networks of workstations communicating via MPI. The detection of cycles (faulty runs) effectively employs the so-called back-level edges. In particular, a parallel level synchronized breadth-first search of the graph is performed to discover all back-level edges, and for each level the back-level edges are checked in parallel by a nested search procedure to confirm or refute the presence of a cycle. Several improvements of the basic algorithm are presented and advantages and drawbacks of their application to distributed LTL model checking are discussed.Research partially supported by grant No. 1ET-408050503 and the Grant Agency of Czech Republic grant No. 201/03/0509.相似文献
In this paper, we focus on the verification approach of Metropolis, an integrated design framework for heterogeneous embedded
systems. The verification approach is based on the formal properties specified in Linear Temporal Logic (LTL) or Logic of
Constraints (LOC). Designs may be refined due to synthesis or be abstracted for verification. An automatic abstraction propagation
algorithm is used to simplify the design for specific properties. A user-defined starting point may also be used with automatic
propagation. Two main verification techniques are implemented in Metropolis the formal verification utilizing the model checker
Spin and the simulation trace checking with automatic generated checkers. Translation algorithms from specification models
to verification models, as well as algorithms of generated checkers are discussed. We use several case studies to demonstrate
our approach for verification of system level designs at multiple levels of abstraction. 相似文献
The ntcc process calculus is a timed concurrent constraint programming (ccp) model equipped with a first-order linear-temporal logic (LTL) for expressing process specifications. A typical behavioral observation in ccp is the strongest postcondition (sp). The ntcc sp denotes the set of all infinite output sequences that a given process can exhibit. The verification problem is then whether the sequences in the sp of a given process satisfy a given ntcc LTL formula.
This paper presents new positive decidability results for timed ccp as well as for LTL. In particular, we shall prove that the following problems are decidable: (1) the sp equivalence for the so-called locally-independentntcc fragment; unlike other fragments for which similar results have been published, this fragment can specify infinite-state systems, (2) verification for locally-independent processes and negation-free first-order formulae of the ntcc LTL, (3) implication for such formulae, (4) Satisfiability for a first-order fragment of Manna and Pnueli's LTL. The purpose of the last result is to illustrate the applicability of ccp to well-established formalisms for concurrency. 相似文献
In this work we propose a verification methodology consisting of selective quantitative timing analysis and interval model checking. Our methods can aid not only in determining if a system works correctly, but also in understanding how well the system works. The selective quantitative algorithms compute minimum and maximum delays over a selected subset of system executions. A linear-time temporal logic (LTL) formula is used to select either infinite paths or finite intervals over which the computation is performed. We show how tableau for LTL formulas can be used for selecting either paths or intervals and also for model checking formulas interpreted over paths or intervals.To demonstrate the usefulness of our methods we have verified a complex and realistic distributed real-time system. Our tool has been able to analyze the system and to compute the response time of the various components. Moreover, we have been able to identify inefficiencies that caused the response time to increase significantly (about 50%). After changing the design we not only verified that the response time was lower, but were also able to determine the causes for the poor performance of the original model using interval model checking. 相似文献