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Accelerating Critical Section Execution with Asymmetric MultiCore Architectures
 In Proceedings of the Int’l Conference on Architectural Support for Programming Language and Operating Systems (ASPLOS
, 2009
"... To improve the performance of a single application on Chip Multiprocessors (CMPs), the application must be split into threads which execute concurrently on multiple cores. In multithreaded applications, critical sections are used to ensure that only one thread accesses shared data at any given time ..."
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Cited by 66 (3 self)
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To improve the performance of a single application on Chip Multiprocessors (CMPs), the application must be split into threads which execute concurrently on multiple cores. In multithreaded applications, critical sections are used to ensure that only one thread accesses shared data at any given time. Critical sections can serialize the execution of threads, which significantly reduces performance and scalability. This paper proposes Accelerated Critical Sections (ACS), a technique that leverages the highperformance core(s) of an Asymmetric Chip Multiprocessor (ACMP) to accelerate the execution of critical sections. In ACS, selected critical sections are executed by a highperformance core, which can execute the critical section faster than the other, smaller cores. Consequently, ACS reduces serialization: it lowers the likelihood of threads waiting for a critical section to finish. Our evaluation on a set of 12 criticalsectionintensive workloads shows that ACS reduces the average execution time by 34 % compared to an equalarea 32core symmetric CMP and by 23 % compared to an equalarea ACMP. Moreover, for 7 of the 12 workloads, ACS also increases scalability (i.e. the number of threads at which performance saturates).
What is a `Good' Encoding of Guarded Choice?
 INFORMATION AND COMPUTATION
, 1997
"... The calculus with synchronous output and mixedguarded choices is strictly more expressive than the calculus with asynchronous output and no choice. As a corollary, Palamidessi recently proved that there is no fully compositional encoding from the former into the latter that preserves divergenc ..."
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Cited by 66 (2 self)
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The calculus with synchronous output and mixedguarded choices is strictly more expressive than the calculus with asynchronous output and no choice. As a corollary, Palamidessi recently proved that there is no fully compositional encoding from the former into the latter that preserves divergencefreedom and symmetries. This paper shows
Sharedmemory mutual exclusion: Major research trends since
 Distributed Computing
, 1986
"... * Exclusion: At most one process executes its critical section at any time. ..."
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Cited by 59 (6 self)
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* Exclusion: At most one process executes its critical section at any time.
The Mutual Exclusion Problem  Part II: Statement and Solutions
, 2000
"... The theory developed in Part I is used to state the mutual exclusion problem and several additional fairness and failuretolerance requirements. Four "distributed " Nprocess solutions are given, ranging from a solution requiring only one communication bit per process that permits individu ..."
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Cited by 57 (2 self)
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The theory developed in Part I is used to state the mutual exclusion problem and several additional fairness and failuretolerance requirements. Four "distributed " Nprocess solutions are given, ranging from a solution requiring only one communication bit per process that permits individual starvation, to one requiring about N ! communication bits per process that satisfies every reasonable fairness and failuretolerance requirement that we can conceive of. Contents 1 Introduction 3 2 The Problem 4 2.1 Basic Requirements . . . . . . . . . . . . . . . . . . . . . . . . 4 2.2 Fairness Requirements . . . . . . . . . . . . . . . . . . . . . . 6 2.3 Premature Termination . . . . . . . . . . . . . . . . . . . . . 8 2.4 Failure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 3 The Solutions 14 3.1 The Mutual Exclusion Protocol . . . . . . . . . . . . . . . . . 15 3.2 The OneBit Solution . . . . . . . . . . . . . . . . . . . . . . 17 3.3 A Digression . . . . . . . . . . . ...
Modular finegrained concurrency verification
"... Traditionally, concurrent data structures are protected by a single mutual exclusion lock so that only one thread may access the data structure at any time. This coarsegrained approach makes it relatively easy to reason about correctness, but it severely limits parallelism. More advanced algorithms ..."
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Cited by 53 (7 self)
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Traditionally, concurrent data structures are protected by a single mutual exclusion lock so that only one thread may access the data structure at any time. This coarsegrained approach makes it relatively easy to reason about correctness, but it severely limits parallelism. More advanced algorithms instead perform synchronisation at a finer grain. They employ sophisticated synchronisation schemes (both blocking and nonblocking) and are usually written in lowlevel languages such as C. This dissertation addresses the formal verification of such algorithms. It proposes techniques that are modular (and hence scalable), easy for programmers to use, and yet powerful enough to verify complex algorithms. In doing so, it makes two theoretical and two practical contributions to reasoning about finegrained concurrency. First, building on rely/guarantee reasoning and separation logic, it develops a new logic, RGSep, that subsumes these two logics and enables simple, modular proofs of finegrained concurrent algorithms that use complex dynamically allocated data structures and may explicitly deallocate memory. RGSep allows for ownershipbased reasoning and ownership
Indexed Predicate Discovery for Unbounded System Verification
 IN CAV’04
, 2004
"... Predicate abstraction has been proved effective for verifying several infinitestate systems. In predicate abstraction, an abstract system is automatically constructed given a set of predicates. Predicate abstraction coupled with automatic predicate discovery provides for a completely automatic v ..."
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Cited by 52 (8 self)
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Predicate abstraction has been proved effective for verifying several infinitestate systems. In predicate abstraction, an abstract system is automatically constructed given a set of predicates. Predicate abstraction coupled with automatic predicate discovery provides for a completely automatic verification scheme. For systems with unbounded integer state variables (e.g. software), counterexample guided predicate discovery has been successful in identifying the necessary predicates. For
The Mutual Exclusion Problem  Part I: A Theory of Interprocess Communication
, 2000
"... A novel formal theory of concurrent systems is introduced that does not assume any atomic operations. The execution of a concurrent program is modeled as an abstract set of operation executions with two temporal ordering relations: "precedence" and "can causally a#ect". A primiti ..."
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Cited by 49 (3 self)
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A novel formal theory of concurrent systems is introduced that does not assume any atomic operations. The execution of a concurrent program is modeled as an abstract set of operation executions with two temporal ordering relations: "precedence" and "can causally a#ect". A primitive interprocess communication mechanism is then defined. In Part II, the mutual exclusion is expressed precisely in terms of this model, and solutions using the communication mechanism are given. Contents 1 Introduction 2 2 The Model 2 2.1 Physical Considerations . . . . . . . . . . . . . . . . . . . . . 3 2.2 System Executions . . . . . . . . . . . . . . . . . . . . . . . . 5 2.3 HigherLevel Views . . . . . . . . . . . . . . . . . . . . . . . . 7 3 Interprocess Communication 9 4 Processes 14 5 MultipleReader Variables 17 6 Discussion of the Assumptions 18 7 Conclusion 19 1 1 Introduction The mutual exclusion problem was first described and solved by Dijkstra in [3]. In this problem, there is a collection...
A classification of symbolic transition systems
 ACM TRANSACTIONS ON COMPUTATIONAL LOGIC
, 2005
"... We define five increasingly comprehensive classes of infinitestate systems, called STS1STS5, whose state spaces have finitary structure. For four of these classes, we provide examples from hybrid systems.STS1 These are the systems with finite bisimilarity quotients. They can be analyzed symbolica ..."
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Cited by 47 (5 self)
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We define five increasingly comprehensive classes of infinitestate systems, called STS1STS5, whose state spaces have finitary structure. For four of these classes, we provide examples from hybrid systems.STS1 These are the systems with finite bisimilarity quotients. They can be analyzed symbolically by iteratively applying predecessor and Boolean operations on state sets, starting from a finite number of observable state sets. Any such iteration is guaranteed to terminate in that only a finite number of state sets can be generated. This enables model checking of the μcalculus.STS2 These are the systems with finite similarity quotients. They can be analyzed symbolically by iterating the predecessor and positive Boolean operations. This enables model checking of the existential and universal fragments of the μcalculus.STS3 These are the systems with finite traceequivalence quotients. They can be analyzed symbolically by iterating the predecessor operation and a restricted form of positive Boolean operations (intersection is restricted to intersection with observables). This enables model checking of all ωregular properties, including linear temporal logic.STS4 These are the systems with finite distanceequivalence quotients (two states are equivalent if for every distance d, the same observables can be reached in d transitions). The systems in this class can be analyzed symbolically by iterating the predecessor operation and terminating when no new state sets are generated. This enables model checking of the existential conjunctionfree and universal disjunctionfree fragments of the μcalculus.STS5 These are the systems with finite boundedreachability quotients (two states are equivalent if for every distance d, the same observables can be reached in d or fewer transitions). The systems in this class can be analyzed symbolically by iterating the predecessor operation and terminating when no new states are encountered (this is a weaker termination condition than above). This enables model checking of reachability properties.
Counting Networks and MultiProcessor Coordination (Extended Abstract)
 In Proceedings of the 23rd Annual Symposium on Theory of Computing
, 1991
"... ) James Aspnes Maurice Herlihy y Nir Shavit z Digital Equipment Corporation Cambridge Research Lab CRL 90/11 September 18, 1991 Abstract Many fundamental multiprocessor coordination problems can be expressed as counting problems: processes must cooperate to assign successive values from a g ..."
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Cited by 44 (7 self)
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) James Aspnes Maurice Herlihy y Nir Shavit z Digital Equipment Corporation Cambridge Research Lab CRL 90/11 September 18, 1991 Abstract Many fundamental multiprocessor coordination problems can be expressed as counting problems: processes must cooperate to assign successive values from a given range, such as addresses in memory or destinations on an interconnection network. Conventional solutions to these problems perform poorly because of synchronization bottlenecks and high memory contention. Motivated by observations on the behavior of sorting networks, we offer a completely new approach to solving such problems. We introduce a new class of networks called counting networks, i.e., networks that can be used to count. We give a counting network construction of depth log 2 n using n log 2 n "gates," avoiding the sequential bottlenecks inherent to former solutions, and having a provably lower contention factor on its gates. Finally, to show that counting networks are not ...
Hundreds of Impossibility Results for Distributed Computing
 Distributed Computing
, 2003
"... We survey results from distributed computing that show tasks to be impossible, either outright or within given resource bounds, in various models. The parameters of the models considered include synchrony, faulttolerance, different communication media, and randomization. The resource bounds refe ..."
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Cited by 43 (5 self)
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We survey results from distributed computing that show tasks to be impossible, either outright or within given resource bounds, in various models. The parameters of the models considered include synchrony, faulttolerance, different communication media, and randomization. The resource bounds refer to time, space and message complexity. These results are useful in understanding the inherent difficulty of individual problems and in studying the power of different models of distributed computing.