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169
Algorithms for Scalable Synchronization on SharedMemory Multiprocessors
 ACM Transactions on Computer Systems
, 1991
"... Busywait techniques are heavily used for mutual exclusion and barrier synchronization in sharedmemory parallel programs. Unfortunately, typical implementations of busywaiting tend to produce large amounts of memory and interconnect contention, introducing performance bottlenecks that become marke ..."
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Cited by 486 (31 self)
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Busywait techniques are heavily used for mutual exclusion and barrier synchronization in sharedmemory parallel programs. Unfortunately, typical implementations of busywaiting tend to produce large amounts of memory and interconnect contention, introducing performance bottlenecks that become markedly more pronounced as applications scale. We argue that this problem is not fundamental, and that one can in fact construct busywait synchronization algorithms that induce no memory or interconnect contention. The key to these algorithms is for every processor to spin on separate locallyaccessible ag variables, and for some other processor to terminate the spin with a single remote write operation at an appropriate time. Flag variables may be locallyaccessible as a result of coherent caching, or by virtue of allocation in the local portion of physically distributed shared memory. We present a new scalable algorithm for spin locks that generates O(1) remote references per lock acquisition, independent of the number of processors attempting to acquire the lock. Our algorithm provides reasonable latency in the absence of contention, requires only a constant amount of space per lock, and requires no hardware support other than
Proving the Correctness of Multiprocess Programs
, 1977
"... The inductive assertion method is generalized to permit formal, machineverifiable proofs of correctness for multiprocess programs. Individual processes are represented by ordinary flowcharts, and no special synchronization mechanisms are assumed, so the method can be applied to a large class of mul ..."
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Cited by 300 (19 self)
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The inductive assertion method is generalized to permit formal, machineverifiable proofs of correctness for multiprocess programs. Individual processes are represented by ordinary flowcharts, and no special synchronization mechanisms are assumed, so the method can be applied to a large class of multiprocess programs. A correctness proof can be designed together with the program by a hierarchical process of stepwise refinement, making the method practical for larger programs. The resulting proofs tend to be natural formalizations of the informal proofs that are now used.
The Octagon Abstract Domain
"... ... domain for static analysis by abstract interpretation. It extends a former numerical abstract domain based on DifferenceBound Matrices and allows us to represent invariants of the form (±x ± y ≤ c), where x and y are program variables and c is a real constant. We focus on giving an efficient re ..."
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Cited by 229 (23 self)
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... domain for static analysis by abstract interpretation. It extends a former numerical abstract domain based on DifferenceBound Matrices and allows us to represent invariants of the form (±x ± y ≤ c), where x and y are program variables and c is a real constant. We focus on giving an efficient representation based on DifferenceBound Matrices—O(n²) memory cost, where n is the number of variables—and graphbased algorithms for all common abstract operators—O(n³) time cost. This includes a normal form algorithm to test equivalence of representation and a widening operator to compute least fixpoint approximations.
Concurrent Reading and Writing
, 1977
"... The problem of sharing data among asynchronous processes is considered. It is assumed that only one process at a time can modify the data, but concurrent reading and writing is permitted. Two general theorems are proved, and some algorithms are presented to illustrate their use. These include a solu ..."
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Cited by 110 (3 self)
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The problem of sharing data among asynchronous processes is considered. It is assumed that only one process at a time can modify the data, but concurrent reading and writing is permitted. Two general theorems are proved, and some algorithms are presented to illustrate their use. These include a solution to the general problem in which a read is repeated if it might have obtained an incorrect result, and two techniques for transmitting messages between processes. These solutions do not assume any synchronizing mechanism other than data which can be written by one process and read by other processes.
Basic Techniques for the Efficient Coordination of Very Large Numbers of Cooperating Sequential Processors
, 1981
"... In this paper we implement several basic operating system primitives by using a "replaceadd" operation, which can supersede the standard "test and set", and which appears to be a universal primitive for efficiently coordinating large numbers of independently acting sequential processors. We also pr ..."
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Cited by 89 (2 self)
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In this paper we implement several basic operating system primitives by using a "replaceadd" operation, which can supersede the standard "test and set", and which appears to be a universal primitive for efficiently coordinating large numbers of independently acting sequential processors. We also present a hardware implementation of replaceadd that permits multiple replaceadds to be processed nearly as efficiently as loads and stores. Moreover, the crucial special case of concurrent replaceadds updating the same variable is handled particularly well: If every PE simultaneously addresses a replaceadd at the same variable, all these requests are satisfied in the time required to process just one request.
Powerful Techniques for the Automatic Generation of Invariants
 In CAV
, 1996
"... . When proving invariance properties of programs one is faced with two problems. The first problem is related to the necessity of proving tautologies of the considered assertion language, whereas the second manifests in the need of finding sufficiently strong invariants. This paper focuses on the se ..."
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Cited by 89 (9 self)
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. When proving invariance properties of programs one is faced with two problems. The first problem is related to the necessity of proving tautologies of the considered assertion language, whereas the second manifests in the need of finding sufficiently strong invariants. This paper focuses on the second problem and describes techniques for the automatic generation of invariants. The first set of these techniques is applicable on sequential transition systems and allows to derive socalled local invariants, i.e. predicates which are invariant at some control location. The second is applicable on networks of transition systems and allows to combine local invariants of the sequential components to obtain local invariants of the global systems. Furthermore, a refined strengthening technique is presented that allows to avoid the problem of sizeincrease of the considered predicates which is the main drawback of the usual strengthening technique. The proposed techniques are illustrated by ex...
Secure and Scalable Replication in Phalanx
 In Proceedings of the 17th IEEE Symposium on Reliable Distributed Systems
, 1998
"... ) Dahlia Malkhi Michael K. Reiter AT&T Labs Research, Florham Park, NJ, USA fdalia,reiterg@research.att.com Abstract Phalanx is a software system for building a persistent, survivable data repository that supports shared data abstractions (e.g., variables, mutual exclusion) for clients. Phalanx ..."
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Cited by 88 (8 self)
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) Dahlia Malkhi Michael K. Reiter AT&T Labs Research, Florham Park, NJ, USA fdalia,reiterg@research.att.com Abstract Phalanx is a software system for building a persistent, survivable data repository that supports shared data abstractions (e.g., variables, mutual exclusion) for clients. Phalanx implements data abstractions that ensure useful properties without trusting the servers supporting these abstractions or the clients accessing them, i.e., Phalanx can survive even the arbitrarily malicious corruption of clients and (some number of) servers. At the core of the system are survivable replication techniques that enable efficient scaling to hundreds of Phalanx servers. In this paper we describe the implementation of some of the data abstractions provided by Phalanx, discuss their ability to scale to large systems, and describe an example application. 1. Introduction In this paper we introduce Phalanx, a software system for building persistent services that support shared data ab...
Scheme: An interpreter for extended lambda calculus
 MEMO 349, MIT AI LAB
, 1975
"... Inspired by ACTORS [7, 17], we have implemented an interpreter for a LISPlike language, SCHEME, based on the lambda calculus [2], but extended for side effects, multiprocessing, and process synchronization. The purpose of this implementation is tutorial. We wish to: 1. alleviate the confusion cause ..."
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Cited by 74 (3 self)
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Inspired by ACTORS [7, 17], we have implemented an interpreter for a LISPlike language, SCHEME, based on the lambda calculus [2], but extended for side effects, multiprocessing, and process synchronization. The purpose of this implementation is tutorial. We wish to: 1. alleviate the confusion caused by MicroPLANNER, CONNIVER, etc., by clarifying the embedding of nonrecursive control structures in a recursive host language like LISP. 2. explain how to use these control structures, independent of such issues as pattern matching and data base manipulation. 3. have a simple concrete experimental domain for certain issues of programming semantics and style. This paper is organized into sections. The first section is a short “reference manual ” containing specifications for all the unusual features of SCHEME. Next, we present a sequence of programming examples which illustrate various programming styles, and how to use them. This will raise certain issues of semantics which we will try to clarify with lambda calculus in the third section. In the fourth section we will give a general discussion of the issues facing an implementor of an interpreter for a language based on lambda calculus. Finally, we will present a completely annotated interpreter for SCHEME, written in MacLISP [13], to acquaint programmers with the tricks of the trade of implementing nonrecursive control structures in a recursive language like LISP.
Constructing TwoWriter Atomic Registers
, 1987
"... In this paper, we construct a 2writer, nreader atomic memory register from two lwriter, (n + l)reader atomic memory registers. There are no restrictions on the size of the constructed register. The simulation requires only a single extra bit per real register, and can survive the failure of any ..."
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Cited by 72 (0 self)
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In this paper, we construct a 2writer, nreader atomic memory register from two lwriter, (n + l)reader atomic memory registers. There are no restrictions on the size of the constructed register. The simulation requires only a single extra bit per real register, and can survive the failure of any set of readers and writers. This construction is a part of a systematic investigation of register simulations, by several researchers.
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 64 (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