Results 1  10
of
433
Software Transactional Memory
, 1995
"... As we learn from the literature, flexibility in choosing synchronization operations greatly simplifies the task of designing highly concurrent programs. Unfortunately, existing hardware is inflexible and is at best on the level of a Load Linked/Store Conditional operation on a single word. Building ..."
Abstract

Cited by 691 (14 self)
 Add to MetaCart
(Show Context)
As we learn from the literature, flexibility in choosing synchronization operations greatly simplifies the task of designing highly concurrent programs. Unfortunately, existing hardware is inflexible and is at best on the level of a Load Linked/Store Conditional operation on a single word. Building on the hardware based transactional synchronization methodology of Herlihy and Moss, we offer software transactional memory (STM), a novel software method for supporting flexible transactional programming of synchronization operations. STM is nonblocking, and can be implemented on existing machines using only a Load Linked/Store Conditional operation. We use STM to provide a general highly concurrent method for translating sequential object implementations to lockfree ones based on implementing a kword compare&swap STMtransaction. Empirical evidence collected on simulated multiprocessor architectures shows that the our method always outperforms all the lockfree translation methods in ...
Composing Specifications
 ACM TRANSACTIONS ON PROGRAMMING LANGUAGES AND SYSTEMS
, 1993
"... ..."
(Show Context)
Interface Automata
 Proceedings of the Ninth Annual Symposium on Foundations of Software Engineering (FSE), ACM
, 2001
"... Conventional type systems specify interfaces in terms of values and domains. ..."
Abstract

Cited by 455 (23 self)
 Add to MetaCart
Conventional type systems specify interfaces in terms of values and domains.
Probabilistic Simulations for Probabilistic Processes
, 1994
"... Several probabilistic simulation relations for probabilistic systems are defined and evaluated according to two criteria: compositionality and preservation of "interesting" properties. Here, the interesting properties of a system are identified with those that are expressible in an untimed ..."
Abstract

Cited by 367 (22 self)
 Add to MetaCart
(Show Context)
Several probabilistic simulation relations for probabilistic systems are defined and evaluated according to two criteria: compositionality and preservation of "interesting" properties. Here, the interesting properties of a system are identified with those that are expressible in an untimed version of the Timed Probabilistic concurrent Computation Tree Logic (TPCTL) of Hansson. The definitions are made, and the evaluations carried out, in terms of a general labeled transition system model for concurrent probabilistic computation. The results cover weak simulations, which abstract from internal computation, as well as strong simulations, which do not.
Computing Simulations on Finite and Infinite Graphs
, 1996
"... . We present algorithms for computing similarity relations of labeled graphs. Similarity relations have applications for the refinement and verification of reactive systems. For finite graphs, we present an O(mn) algorithm for computing the similarity relation of a graph with n vertices and m edges ..."
Abstract

Cited by 186 (6 self)
 Add to MetaCart
(Show Context)
. We present algorithms for computing similarity relations of labeled graphs. Similarity relations have applications for the refinement and verification of reactive systems. For finite graphs, we present an O(mn) algorithm for computing the similarity relation of a graph with n vertices and m edges (assuming m n). For effectively presented infinite graphs, we present a symbolic similaritychecking procedure that terminates if a finite similarity relation exists. We show that 2D rectangular automata, which model discrete reactive systems with continuous environments, define effectively presented infinite graphs with finite similarity relations. It follows that the refinement problem and the 8CTL modelchecking problem are decidable for 2D rectangular automata. 1 Introduction A labeled graph G = (V; E;A; hh\Deltaii) consist of a (possibly infinite) set V of vertices, a set E ` V 2 of edges, a set A of labels, and a function hh\Deltaii : V ! A that maps each vertex v to a label hh...
Atomic Snapshots of Shared Memory
, 1993
"... . This paper introduces a general formulation of atomic snapshot memory, a shared memory partitioned into words written (updated) by individual processes, or instantaneously read (scanned) in its entirety. This paper presents three waitfree implementations of atomic snapshot memory. The first imple ..."
Abstract

Cited by 184 (51 self)
 Add to MetaCart
. This paper introduces a general formulation of atomic snapshot memory, a shared memory partitioned into words written (updated) by individual processes, or instantaneously read (scanned) in its entirety. This paper presents three waitfree implementations of atomic snapshot memory. The first implementation in this paper uses unbounded (integer) fields in these registers, and is particularly easy to understand. The second implementation uses bounded registers. Its correctness proof follows the ideas of the unbounded implementation. Both constructions implement a singlewriter snapshot memory, in which each word may be updated by only one process, from singlewriter, nreader registers. The third algorithm implements a multiwriter snapshot memory from atomic nwriter, nreader registers, again echoing key ideas from the earlier constructions. All operations require \Theta(n 2 ) reads and writes to the component shared registers in the worst case. Categories and Subject Discriptors:...
Interaction and Intelligent Behavior
, 1994
"... This thesis addresses situated, embodied agents interacting in complex domains. It focuses on two problems: 1) synthesis and analysis of intelligent group behavior, and 2) learning in complex group environments. Basic behaviors, control laws that cluster constraints to achieve particular goals and h ..."
Abstract

Cited by 175 (20 self)
 Add to MetaCart
This thesis addresses situated, embodied agents interacting in complex domains. It focuses on two problems: 1) synthesis and analysis of intelligent group behavior, and 2) learning in complex group environments. Basic behaviors, control laws that cluster constraints to achieve particular goals and have the appropriate compositional properties, are proposed as effective primitives for control and learning. The thesis describes the process of selecting such basic behaviors, formally specifying them, algorithmically implementing them, and empirically evaluating them. All of the proposed ideas are validated with a group of up to 20 mobile robots using a basic behavior set consisting of: safewandering, following, aggregation, dispersion, and homing. The set of basic behaviors acts as a substrate for achieving more complex highlevel goals and tasks. Two behavior combination operators are introduced, and verified by combining subsets of the above basic behavior set to implement collective flocking, foraging, and docking. A methodology is introduced for automatically constructing higherlevel behaviors
Conversation specification: a new approach to design and analysis of eservice composition
 In World Wide Web Conference
, 2003
"... This paper introduces a framework for modeling and specifying the global behavior of eservice compositions. Under this framework, peers (individual eservices) communicate through asynchronous messages and each peer maintains a queue for incoming messages. A global “watcher ” keeps track of message ..."
Abstract

Cited by 173 (29 self)
 Add to MetaCart
(Show Context)
This paper introduces a framework for modeling and specifying the global behavior of eservice compositions. Under this framework, peers (individual eservices) communicate through asynchronous messages and each peer maintains a queue for incoming messages. A global “watcher ” keeps track of messages as they occur. We propose and study a central notion of a “conversation”, which is a sequence of (classes of) messages observed by the watcher. We consider the case where the peers are represented by Mealy machines (finite state machines with input and output). The sets of conversations exhibit unexpected behaviors. For example, there exists a composite eservice based on Mealy peers whose set of conversations is not context free (and not regular). (The set of conversations is always context sensitive.) One cause for this is the queuing of messages; we introduce an operator “prepone ” that simulates queue