PPT-Concurrency/synchronization using UML state models

April 14 th 2008 Michigan State University Overview State models of monitor objects Monitorprocess pattern Heuristic for generating correct synchronization code from a state model Use of signal vs broadcast to notify waiting threads. and . efficient. implementations of . synchronous. models on . asynchronous. execution platforms. Stavros . Tripakis. UC Berkeley and . Verimag. EC^2 Workshop, Grenoble, June 2009. Some observations. Slides. are . mainly. . taken. from «O. perating. Systems: Internals and Design Principles”, . 8/E . William Stallings (Chapter . 5). . Sistemi di Calcolo (II semestre) – Roberto Baldoni. Multiple Processes. CSCI 201L. Jeffrey Miller, Ph.D.. http://www-scf.usc.edu/~csci201. USC CSCI 201L. Outline. USC CSCI 201L. 2. /9. Synchronization. Critical Section. Motivation for Synchronization. Thread synchronization is used to coordinate the execution of dependent threads. Prof. O. Nierstrasz. Selected material © Magee and Kramer. © Oscar Nierstrasz. 2. Roadmap. Modelling Concurrency. Finite State Processes . Labelled Transition Systems. Java Threads. Thread creation. Rui. . Gu. , . Guoliang. . Jin. , . Linhai. Song, . Linjie. Zhu, Shan Lu. University . of Wisconsin – Madison, USA. Proper Thread Synchronization . is . Hard. Very easy to get things wrong. H. ard-to-find concurrency bugs(Data race, Atomicity Violation, Dead Lock). Hakim Weatherspoon. CS 3410, Spring 2012. Computer Science. Cornell University. P&H Chapter 2.11. Administrivia. Pizza . party: PA3 Games Night. Friday, April 27. th. , 5:00-7:00pm. Location: Upson . . draft-dimitri-ospf-phased-db-sync-00.txt. Dimitri Papadimitriou. Alcatel-Lucent. IETF 79 – Beijing. November 7-12, 2010. Motivation. Opaque LSAs . OSPF extensibility: information contained in Opaque LSAs often used by application wishing to distribute information throughout OSPF domain (so called "non-IP routing information"). in Wireless Sensor Networks. Philipp Sommer. Roger Wattenhofer. Time Synchronization is a well-studied Problem. Time, Clocks, and the Ordering of Events in a Distributed System. L. Lamport, Communications of the ACM, 1978.. Multicore. Programming. Brendan Lynch. Introduction. Synchronization techniques. l. ocks, barriers, non-blocking approaches, atomic primitives. Concurrent memory paradigms. s. hared memory, . d. istributed memory. Dr. Yanqing Zhang. Agenda. Overview. Synchronization Techniques. WebDAV(Web Distributed Authoring and Versioning). Future Work. References. What is Synchronization?. In general it is . process of precisely coordinating or matching two or more activities, devices, or processes in time.. Software & the Concurrency Revolution by Sutter & Larus ACM Queue Magazine, Sept. 2005 For CMPS 5433 - Halverson 1 In a Nutshell “The concurrency revolution is primarily a software revolution The Desired Brand Effect Stand Out in a Saturated Market with a Timeless Brand The Desired Brand Effect Stand Out in a Saturated Market with a Timeless Brand Replication Benefits. Replication enhances tolerance to failure. Performance can be improved in different ways. Placing replicas in the proximity of the process using them. Replicating servers and subsequently dividing the work among them.