On Cyclic Process Dependencies and the Veriication of Absence of Deadlocks in Reactive Systems

نویسندگان

  • Richard Carlsson
  • Stephen P. Masticola
چکیده

We introduce the class of weak process dependency relations, and give deenitions of starvation and deadlock cycles in terms of these. We show the usefulness of our deenitions in reasoning about deadlocks, in the general sense of all forms of innnite process suspension, including the local form also known as livelock. In particular, we make a formal distinction between three complementary cases of deadlock: starvation, deadlock cycles, and a form we call non-closing deadlocks. Furthermore, we state assumptions under which absence of deadlocks may be veriied for a program by verifying absence of deadlock cycles, and discuss when dependencies between deadlocked processes can safely be excluded. We give a generalised framework for verifying absence of deadlock cycles, in terms of our deenitions, extending the method developed by Stephen P. Masticola to local deadlocks. Lastly, we demonstrate how Masticola's method can be mapped onto our framework, and brieey discuss the relation between resource allocation dependencies and weak process dependency relations.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

A Methodology for Unified Assessment of Physical and Geographical Dependencies of Wide Area Measurement Systems in Smart Grids

Wide Area Measurement Systems (WAMS) enable real time monitoring and control of smart grids by combining digital measurement devices, communication and control systems. As WAMS consist of various infrastructures, they imply complex dependencies among their underlying systems and components of different types, such as cyber, physical and geographical dependencies. Although several works exist in...

متن کامل

Formal Veri cation of Robotic Missions and Tasks

An undersea robot like a long range AUV is a typical example of critical system, like a satellite or a planetary rover. We mean here that, for such a system, any repairing or recovery operation, even a mission reconnguration, which would involve the intervention of a human operator is always costly, often diicult and sometimes impossible. This is why such systems should be at least provided wit...

متن کامل

An experimental study on the determination of gantry angle and SSD dependencies of TLD and MOSFET dosimeter systems

Background: The purpose of this study was to investigate the various gantry angle and SSD dependencies of TLD and MOSFET dosimeters. Materials and Methods: LiF (Mg) TLD and MOSFET were used in this study. Dosimeter systems were calibrated and then irradiated at various gantry angle and SSD by applying 6 MV photon energy. Results: Based on the results, MOSFET changes were found to be in 2% range...

متن کامل

A Survey on Kernel

Formal methods have been traditionally used to model and verify operating systems. Different methods verify diierent operating systems properties, such as process management, mutual exclusion and inter-process communication. Moreover, various methods may capture diierent design errors, such as deadlocks or unspeciied receptions. The system kernel supports higher-level system services. Hence, ke...

متن کامل

Study of Photooxidative Degradation of Reactive Dyes from Aqueous Solutions by UV/ C102 Process

The color removal of three reactive dyes in an aquatic system without priortreatment was studied. Selected commercial dyes were treated with NaC102 andUV as oxidation agents. Effects of nature of oxidant, temperature, pH ofsolutions, concentration of C107—, contact time of C102— and UV irradiation wereinvestigated. Optimal C102— concentration for color removal in the absence of UVirradiation wa...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:

دوره   شماره 

صفحات  -

تاریخ انتشار 1997