CS 636: Shared Memory Synchronization Swarnendu Biswas

Total Page:16

File Type:pdf, Size:1020Kb

CS 636: Shared Memory Synchronization Swarnendu Biswas CS 636: Shared Memory Synchronization Swarnendu Biswas Semester 2020-2021-II CSE, IIT Kanpur Content influenced by many excellent references, see References slide for acknowledgements. What is the desired property? class Set { final Vector elems = new Vector(); void add(Object x) { if (!elems.contains(x)) { elems.add(x); } } } class Vector { synchronized void add(Object o) { ... } synchronized boolean contains(Object o) { ... } } CS 636 Swarnendu Biswas What is the desired property? Q.insert(elem): Q.remove(): atomic { atomic { while (Q.full()) {} while (Q.empty()) {} // Add elem to the Q // Return data from Q } } CS 636 Swarnendu Biswas Synchronization Patterns • Mutual exclusion lock:bool := false Lock.acquire(): Lock.release(): while TAS(&lock) lock := false // spin • Condition synchronization while ¬ condition // do nothing (spin) • Global synchronization CS 636 Swarnendu Biswas Locks (Mutual Exclusion) public interface Lock { Lock mtx = new LockImpl(…); public void lock(); … public void unlock(); } mtx.lock(); … try { public class LockImpl … // body implements Lock { } finally { … mtx.unlock(); … } } CS 636 Swarnendu Biswas Desired Synchronization Properties • Mutual exclusion • Critical sections on the same lock from different threads do not overlap • Safety property • Livelock freedom If a lock is available, then some thread should be able to acquire it within bounded steps CS 636 Swarnendu Biswas Deadlock-Free • If some thread calls lock() – And never returns – Then other threads must complete lock() and unlock() calls infinitely often • System as a whole makes progress – Even if individuals starve Art of Multiprocessor Programming 7 Starvation-Free • If some thread calls lock() – It will eventually return • Individual threads make progress Art of Multiprocessor Programming 8 Desired Synchronization Properties • Deadlock freedom • If a thread attempts to acquire the lock, then some thread should be able to acquire the lock • Individual threads may starve • Liveness property • Starvation freedom • Every thread that acquires a lock eventually releases it • A lock acquire request must eventually succeed within bounded steps • Implies deadlock freedom CS 636 Swarnendu Biswas Classic Mutual Exclusion Algorithms CS 636 Swarnendu Biswas LockOne: What could go wrong? class LockOne implements Lock { private boolean[] flag = new boolean[2]; public void lock() { flag[i] = true; j = 1-i; while (flag[j]) {} } } Art of Multiprocessor Programming 12 Deadlock Freedom • LockOne Fails deadlock-freedom – Concurrent execution can deadlock flag[i] = true; flag[j] = true; while (flag[j]){} while (flag[i]){} – Sequential executions OK Art of Multiprocessor Programming 13 LockOne Satisfies Mutual Exclusion j k • Assume CSA overlaps CSB • Consider each thread's last (j-th and k-th) read and write in the lock() method before entering • Derive a contradiction Art of Multiprocessor Programming 14 From the Code • writeA(flag[A]=true) → readA(flag[B]==false) →CSA • writeB(flag[B]=true) → readB(flag[A]==false) → CSB class LockOne implements Lock { … public void lock() { flag[i] = true; j = 1 – i; while (flag[j]) {} } } Art of Multiprocessor Programming 15 From the Assumption • readA(flag[B]==false) → writeB(flag[B]=true) • readB(flag[A]==false) → writeA(flag[B]=true) Art of Multiprocessor Programming 16 Combining • Assumptions: – readA(flag[B]==false) → writeB(flag[B]=true) – readB(flag[A]==false) → writeA(flag[A]=true) • From the code – writeA(flag[A]=true) → readA(flag[B]==false) – writeB(flag[B]=true) → readB(flag[A]==false) Art of Multiprocessor Programming 17 Combining • Assumptions: – readA(flag[B]==false) → writeB(flag[B]=true) – readB(flag[A]==false) → writeA(flag[A]=true) • From the code – writeA(flag[A]=true) → readA(flag[B]==false) – writeB(flag[B]=true) → readB(flag[A]==false) Art of Multiprocessor Programming 18 Combining • Assumptions: – readA(flag[B]==false) → writeB(flag[B]=true) – readB(flag[A]==false) → writeA(flag[A]=true) • From the code – writeA(flag[A]=true) → readA(flag[B]==false) – writeB(flag[B]=true) → readB(flag[A]==false) Art of Multiprocessor Programming 19 Combining • Assumptions: – readA(flag[B]==false) → writeB(flag[B]=true) – readB(flag[A]==false) → writeA(flag[A]=true) • From the code – writeA(flag[A]=true) → readA(flag[B]==false) – writeB(flag[B]=true) → readB(flag[A]==false) Art of Multiprocessor Programming 20 Combining • Assumptions: – readA(flag[B]==false) → writeB(flag[B]=true) – readB(flag[A]==false) → writeA(flag[A]=true) • From the code – writeA(flag[A]=true) → readA(flag[B]==false) – writeB(flag[B]=true) → readB(flag[A]==false) Art of Multiprocessor Programming 21 Combining • Assumptions: – readA(flag[B]==false) → writeB(flag[B]=true) – readB(flag[A]==false) → writeA(flag[A]=true) • From the code – writeA(flag[A]=true) → readA(flag[B]==false) – writeB(flag[B]=true) → readB(flag[A]==false) Art of Multiprocessor Programming 22 Cycle! Art of Multiprocessor Programming 23 LockTwo: What could go wrong? public class LockTwo implements Lock { private int victim; public void lock() { victim = i; while (victim == i) {}; } public void unlock() {} } Art of Multiprocessor Programming 25 LockTwo Claims • Satisfies mutual exclusion – If thread i in CS public void LockTwo() { – Then victim == j victim = i; – Cannot be both 0 and 1 while (victim == i) {}; } • Not deadlock free – Sequential execution deadlocks – Concurrent execution does not Art of Multiprocessor Programming 26 Peterson’s Algorithm class PetersonLock { public void lock() { int i = ThreadID.get(); static volatile boolean[] flag = int j = 1-i; new boolean[2]; flag[i] = true; static volatile int victim; victim = i; while (flag[j] && victim == i) {} public void unlock() { } int i = ThreadID.get(); flag[i] = false; } } CS 636 Swarnendu Biswas Mutual Exclusion public void lock() { flag[i] = true; victim = i; while (flag[j] && victim == i) {}; • If thread 0 in • If thread 1 in critical section, critical section, – flag[0]=true, – flag[1]=true, – victim = 1 – victim = 0 Cannot both be true Art of Multiprocessor Programming 28 Starvation Free • Thread i blocked only if j repeatedly public void lock() { flag[i] = true; re-enters so that victim = i; while (flag[j] && victim == i) {}; flag[j] == true and } victim == i public void unlock() { flag[i] = false; • When j re-enters } – it sets victim to j. – So i gets in Art of Multiprocessor Programming 29 Deadlock Free public void lock() { … while (flag[j] && victim == i) {}; • Thread blocked – only at while loop – only if it is the victim • One or the other must not be the victim Art of Multiprocessor Programming 30 Peterson’s Algorithm class PetersonLock { public void lock() { int i = ThreadID.get(); static volatile boolean[] flag = int j = 1-i; new boolean[2]; flag[i] = true; static volatile int victim; victim = i; while (flag[j] && victim == i) {} public void unlock() { } int i = ThreadID.get(); flag[i] = false; •} Is this algorithm correct under } sequential consistency? • What if we do not have sequential consistency? CS 636 Swarnendu Biswas Filter Lock for n Threads non-CS with n threads level=0 • There are n-1 waiting rooms n-1 threads level=1 called “levels” • At least one thread trying to enter a level succeeds • One thread gets blocked at each level if many threads try to enter 2 threads level=n-2 CS level=n-1 CS 636 Swarnendu Biswas Filter Lock class FilterLock { public void unlock() { int me = ThreadID.get(); volatile int[] level; level[me]= 0; volatile int[] victim; } public FilterLock() { level = new int[n]; victim = new int[n]; for (int i = 0; i < n; i++) { level[i] = 0; } } CS 636 Swarnendu Biswas Filter Lock … public void lock() { int me = ThreadID.get(); for (int i = 1; i < n; i++) { // Attempt to enter level i level[me] = i; // visit level i victim[i] = me; // Thread “me” is a good guy! // spin while conflict exits while ((∃k != me) level[k] >= i && victim[i] == me) { } } } } CS 636 Swarnendu Biswas Claim • Start at level L=0 • At most n-L threads enter level L • Mutual exclusion at level L=n-1 ncs L=0 L=1 L=n-2 cs L=n-1 Art of Multiprocessor Programming 35 Induction Hypothesis • No more than n-L+1 at level L-1 • Induction step: by contradiction • Assume all at level L-1 enter level L ncs assume • A last to write victim[L] L-1 has n-L+1 L has n-L • B is any other thread at level L cs prove Art of Multiprocessor Programming 36 Proof Structure ncs Assumed to enter L-1 A B n-L+1 = 4 n-L+1 = 4 Last to write cs By way of contradiction victim[L] all enter L Show that A must have seen B in level[L] and since victim[L] == A could not have entered Art of Multiprocessor Programming 37 From the Code (1) writeB(level[B]=L)➔writeB(victim[L]=B) public void lock() { for (int L = 1; L < n; L++) { level[i] = L; victim[L] = i; while (($ k != i) level[k] >= L) && victim[L] == i) {}; }} Art of Multiprocessor Programming 38 From the Code (2) writeA(victim[L]=A)➔readA(level[B]) public void lock() { for (int L = 1; L < n; L++) { level[i] = L; victim[L] = i; while (($ k != i) level[k] >= L) && victim[L] == i) {}; }} Art of Multiprocessor Programming 39 By Assumption (3) writeB(victim[L]=B)➔writeA(victim[L]=A) By assumption, A is the last thread to write victim[L] Art of Multiprocessor Programming 40 Combining Observations (1) writeB(level[B]=L)➔writeB(victim[L]=B) (3) writeB(victim[L]=B)➔writeA(victim[L]=A) (2) writeA(victim[L]=A)➔readA(level[B]) Art of Multiprocessor Programming 41 Combining Observations (1) writeB(level[B]=L)➔writeB(victim[L]=B) (3) writeB(victim[L]=B)➔writeA(victim[L]=A) (2) writeA(victim[L]=A)➔readA(level[B])
Recommended publications
  • Process Synchronisation Background (1)
    Process Synchronisation Background (1) Concurrent access to shared data may result in data inconsistency Maintaining data consistency requires mechanisms to ensure the orderly execution of cooperating processes Producer Consumer Background (2) Race condition count++ could be implemented as register1 = count register1 = register1 + 1 count = register1 count- - could be implemented as register2 = count register2 = register2 - 1 count = register2 Consider this execution interleaving with ―count = 5‖ initially: S0: producer execute register1 = count {register1 = 5} S1: producer execute register1 = register1 + 1 {register1 = 6} S2: consumer execute register2 = count {register2 = 5} S3: consumer execute register2 = register2 - 1 {register2 = 4} S4: producer execute count = register1 {count = 6 } S5: consumer execute count = register2 {count = 4} Solution: ensure that only one process at a time can manipulate variable count Avoid interference between changes Critical Section Problem Critical section: a segment of code in which a process may be changing Process structure common variables ◦ Only one process is allowed to be executing in its critical section at any moment in time Critical section problem: design a protocol for process cooperation Requirements for a solution ◦ Mutual exclusion ◦ Progress ◦ Bounded waiting No assumption can be made about the relative speed of processes Handling critical sections in OS ◦ Pre-emptive kernels (real-time programming, more responsive) Linux from 2.6, Solaris, IRIX ◦ Non-pre-emptive kernels (free from race conditions) Windows XP, Windows 2000, traditional UNIX kernel, Linux prior 2.6 Peterson’s Solution Two process solution Process Pi ◦ Mutual exclusion is preserved? ◦ The progress requirements is satisfied? ◦ The bounded-waiting requirement is met? Assumption: LOAD and STORE instructions are atomic, i.e.
    [Show full text]
  • Gnu Smalltalk Library Reference Version 3.2.5 24 November 2017
    gnu Smalltalk Library Reference Version 3.2.5 24 November 2017 by Paolo Bonzini Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.2 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled \GNU Free Documentation License". 1 3 1 Base classes 1.1 Tree Classes documented in this manual are boldfaced. Autoload Object Behavior ClassDescription Class Metaclass BlockClosure Boolean False True CObject CAggregate CArray CPtr CString CCallable CCallbackDescriptor CFunctionDescriptor CCompound CStruct CUnion CScalar CChar CDouble CFloat CInt CLong CLongDouble CLongLong CShort CSmalltalk CUChar CByte CBoolean CUInt CULong CULongLong CUShort ContextPart 4 GNU Smalltalk Library Reference BlockContext MethodContext Continuation CType CPtrCType CArrayCType CScalarCType CStringCType Delay Directory DLD DumperProxy AlternativeObjectProxy NullProxy VersionableObjectProxy PluggableProxy SingletonProxy DynamicVariable Exception Error ArithmeticError ZeroDivide MessageNotUnderstood SystemExceptions.InvalidValue SystemExceptions.EmptyCollection SystemExceptions.InvalidArgument SystemExceptions.AlreadyDefined SystemExceptions.ArgumentOutOfRange SystemExceptions.IndexOutOfRange SystemExceptions.InvalidSize SystemExceptions.NotFound SystemExceptions.PackageNotAvailable SystemExceptions.InvalidProcessState SystemExceptions.InvalidState
    [Show full text]
  • Learning Javascript Design Patterns
    Learning JavaScript Design Patterns Addy Osmani Beijing • Cambridge • Farnham • Köln • Sebastopol • Tokyo Learning JavaScript Design Patterns by Addy Osmani Copyright © 2012 Addy Osmani. All rights reserved. Revision History for the : 2012-05-01 Early release revision 1 See http://oreilly.com/catalog/errata.csp?isbn=9781449331818 for release details. ISBN: 978-1-449-33181-8 1335906805 Table of Contents Preface ..................................................................... ix 1. Introduction ........................................................... 1 2. What is a Pattern? ...................................................... 3 We already use patterns everyday 4 3. 'Pattern'-ity Testing, Proto-Patterns & The Rule Of Three ...................... 7 4. The Structure Of A Design Pattern ......................................... 9 5. Writing Design Patterns ................................................. 11 6. Anti-Patterns ......................................................... 13 7. Categories Of Design Pattern ............................................ 15 Creational Design Patterns 15 Structural Design Patterns 16 Behavioral Design Patterns 16 8. Design Pattern Categorization ........................................... 17 A brief note on classes 17 9. JavaScript Design Patterns .............................................. 21 The Creational Pattern 22 The Constructor Pattern 23 Basic Constructors 23 Constructors With Prototypes 24 The Singleton Pattern 24 The Module Pattern 27 iii Modules 27 Object Literals 27 The Module Pattern
    [Show full text]
  • Bespoke Tools: Adapted to the Concepts Developers Know
    Bespoke Tools: Adapted to the Concepts Developers Know Brittany Johnson, Rahul Pandita, Emerson Murphy-Hill, and Sarah Heckman Department of Computer Science North Carolina State University, Raleigh, NC, USA {bijohnso, rpandit}@ncsu.edu, {emerson, heckman}@csc.ncsu.edu ABSTRACT Such manual customization is undesirable for several rea- Even though different developers have varying levels of ex- sons. First, to choose among alternative tools, a developer pertise, the tools in one developer's integrated development must be aware that alternatives exist, yet lack of awareness environment (IDE) behave the same as the tools in every is a pervasive problem in complex software like IDEs [3]. other developers' IDE. In this paper, we propose the idea of Second, even after being aware of alternatives, she must be automatically customizing development tools by modeling able to intelligently choose which tool will be best for her. what a developer knows about software concepts. We then Third, if a developer's situation changes and she recognizes sketch three such \bespoke" tools and describe how devel- that the tool she is currently using is no longer the optimal opment data can be used to infer what a developer knows one, she must endure the overhead of switching to another about relevant concepts. Finally, we describe our ongoing ef- tool. Finally, customization takes time, time that is spent forts to make bespoke program analysis tools that customize fiddling with tools rather than developing software. their notifications to the developer using them. 2. WHAT IS THE NEW IDEA? Categories and Subject Descriptors Our idea is bespoke tools: tools that automatically fit D.2.6 [Software Engineering]: Programming Environments| themselves to the developer using them.
    [Show full text]
  • An Analysis of the Dynamic Behavior of Javascript Programs
    An Analysis of the Dynamic Behavior of JavaScript Programs Gregor Richards Sylvain Lebresne Brian Burg Jan Vitek S3 Lab, Department of Computer Science, Purdue University, West Lafayette, IN fgkrichar,slebresn,bburg,[email protected] Abstract becoming a general purpose computing platform with office appli- The JavaScript programming language is widely used for web cations, browsers and development environments [15] being devel- programming and, increasingly, for general purpose computing. oped in JavaScript. It has been dubbed the “assembly language” of the Internet and is targeted by code generators from the likes As such, improving the correctness, security and performance of 2;3 JavaScript applications has been the driving force for research in of Java and Scheme [20]. In response to this success, JavaScript type systems, static analysis and compiler techniques for this lan- has started to garner academic attention and respect. Researchers guage. Many of these techniques aim to reign in some of the most have focused on three main problems: security, correctness and dynamic features of the language, yet little seems to be known performance. Security is arguably JavaScript’s most pressing prob- about how programmers actually utilize the language or these fea- lem: a number of attacks have been discovered that exploit the lan- tures. In this paper we perform an empirical study of the dynamic guage’s dynamism (mostly the ability to access and modify shared behavior of a corpus of widely-used JavaScript programs, and an- objects and to inject code via eval). Researchers have proposed ap- alyze how and why the dynamic features are used.
    [Show full text]
  • Platform SDK Developer's Guide
    Platform SDK Developer's Guide Platform SDK 9.0.x 3/6/2020 Table of Contents Welcome to the Developer's Guide! 4 Introductory Topics 6 Introducing the Platform SDK 7 Architecture of the Platform SDK 12 Connecting to a Server 14 Configuring Platform SDK Channel Encoding for String Values 32 Using the Warm Standby Application Block 33 Using the Application Template Application Block 42 Using the Cluster Protocol Application Block 74 Event Handling 88 Setting up Logging in Platform SDK 100 Additional Logging Features 106 Log4j2 Configuration with the Application Template Application Block 116 Advanced Platform SDK Topics 132 Using Kerberos Authentication in Platform SDK 133 Secure connections using TLS 137 Quick Start 143 TLS and the Platform SDK Commons Library 147 TLS and the Application Template Application Block 160 Configuring TLS Parameters in Configuration Manager 167 Using and Configuring Security Providers 190 OpenSSL Configuration File 201 Use Cases 208 Using and Configuring TLS Protocol Versions 211 Lazy Parsing of Message Attributes 214 Log Filtering 218 Hide or Tag Sensitive Data in Logs 230 Profiling and Performance Services 237 IPv6 Resolution 243 Managing Protocol Configuration 248 Friendly Reaction to Unsupported Messages 252 Creating Custom Protocols 258 JSON Support 267 Working with Custom Servers 276 Bidirectional Messaging 282 Hide Message Attributes in Logs 287 Resources Releasing in an Application Container 289 Transport Layer Substitution 292 Server-Specific Overviews 301 Telephony (T-Server) 302 Introduction to TLib
    [Show full text]
  • Design Patterns for Parsing Dung “Zung” Nguyen Mathias Ricken Stephen Wong Dept
    Design Patterns for Parsing Dung “Zung” Nguyen Mathias Ricken Stephen Wong Dept. of Computer Science Dept. of Computer Science Dept. of Computer Science Rice University Rice University Rice University Houston, TX 77005 Houston, TX 77005 Houston, TX 77005 +1 713-348-3835 +1 713-348-3836 +1 713-348-3814 [email protected] [email protected] [email protected] ABSTRACT be effective, they must progress normally yet quickly to cover We provide a systematic transformation of an LL(1) grammar to topics that are complex enough to make a compelling case for an object model that consists of OOP (see for instance, [2][3]). A wealth of problems in various • an object structure representing the non-terminal symbols and phases of a compiler can be appropriately modeled as object- their corresponding grammar production rules, oriented systems. However, such problems are rarely discussed at the introductory level in current computer science curricula. • a union of classes representing the terminal symbols (tokens). A quick tour of web sites and extant textbooks [4][5][6][7] seems We present a variant form of the visitor pattern and apply it to the to indicate that context-free grammars (CFG) and their related above union of token classes to model a predictive recursive topics are usually relegated to upper division courses in descent parser on the given grammar. Parsing a non-terminal is programming languages and compiler construction. Efforts have represented by a visitor to the tokens. For non-terminals that have been made to introduce object-oriented design patterns such as the more than one production rule, the corresponding visitors are composite and visitor patterns into such courses at the semantic chained together according to the chain of responsibility pattern in analysis phases but not at the syntax analysis phase [5][8].
    [Show full text]
  • Pharo by Example
    Portland State University PDXScholar Computer Science Faculty Publications and Computer Science Presentations 2009 Pharo by Example Andrew P. Black Portland State University, [email protected] Stéphane Ducasse Oscar Nierstrasz University of Berne Damien Pollet University of Lille Damien Cassou See next page for additional authors Let us know how access to this document benefits ouy . Follow this and additional works at: http://pdxscholar.library.pdx.edu/compsci_fac Citation Details Black, Andrew, et al. Pharo by example. 2009. This Book is brought to you for free and open access. It has been accepted for inclusion in Computer Science Faculty Publications and Presentations by an authorized administrator of PDXScholar. For more information, please contact [email protected]. Authors Andrew P. Black, Stéphane Ducasse, Oscar Nierstrasz, Damien Pollet, Damien Cassou, and Marcus Denker This book is available at PDXScholar: http://pdxscholar.library.pdx.edu/compsci_fac/108 Pharo by Example Andrew P. Black Stéphane Ducasse Oscar Nierstrasz Damien Pollet with Damien Cassou and Marcus Denker Version of 2009-10-28 ii This book is available as a free download from http://PharoByExample.org. Copyright © 2007, 2008, 2009 by Andrew P. Black, Stéphane Ducasse, Oscar Nierstrasz and Damien Pollet. The contents of this book are protected under Creative Commons Attribution-ShareAlike 3.0 Unported license. You are free: to Share — to copy, distribute and transmit the work to Remix — to adapt the work Under the following conditions: Attribution. You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work).
    [Show full text]
  • Object-Oriented Design Patterns
    Object-Oriented Design Patterns David Janzen EECS 816 Object-Oriented Software Development University of Kansas Outline • Introduction – Design Patterns Overview – Strategy as an Early Example – Motivation for Creating and Using Design Patterns – History of Design Patterns • Gang of Four (GoF) Patterns – Creational Patterns – Structural Patterns – Behavioral Patterns Copyright © 2006 by David S. 2 Janzen. All rights reserved. What are Design Patterns? • In its simplest form, a pattern is a solution to a recurring problem in a given context • Patterns are not created, but discovered or identified • Some patterns will be familiar? – If you’ve been designing and programming for long, you’ve probably seen some of the patterns we will discuss – If you use Java Foundation Classes (Swing), Copyright © 2006 by David S. 3 you have certaJiannzleyn. Aulls rieghdts rsesoervmed.e design patterns Design Patterns Definition1 • Each pattern is a three-part rule, which expresses a relation between – a certain context, – a certain system of forces which occurs repeatedly in that context, and – a certain software configuration which allows these forces to resolve themselves 1. Dick Gabriel, http://hillside.net/patterns/definition.html Copyright © 2006 by David S. 4 Janzen. All rights reserved. A Good Pattern1 • Solves a problem: – Patterns capture solutions, not just abstract principles or strategies. • Is a proven concept: – Patterns capture solutions with a track record, not theories or speculation 1. James O. Coplien, http://hillside.net/patterns/definition.html Copyright © 2006 by David S. 5 Janzen. All rights reserved. A Good Pattern • The solution isn't obvious: – Many problem-solving techniques (such as software design paradigms or methods) try to derive solutions from first principles.
    [Show full text]
  • IBM ILOG CPLEX Optimization Studio OPL Language Reference Manual
    IBM IBM ILOG CPLEX Optimization Studio OPL Language Reference Manual Version 12 Release 7 Copyright notice Describes general use restrictions and trademarks related to this document and the software described in this document. © Copyright IBM Corp. 1987, 2017 US Government Users Restricted Rights - Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp. Trademarks IBM, the IBM logo, and ibm.com are trademarks or registered trademarks of International Business Machines Corp., registered in many jurisdictions worldwide. Other product and service names might be trademarks of IBM or other companies. A current list of IBM trademarks is available on the Web at "Copyright and trademark information" at www.ibm.com/legal/copytrade.shtml. Adobe, the Adobe logo, PostScript, and the PostScript logo are either registered trademarks or trademarks of Adobe Systems Incorporated in the United States, and/or other countries. Linux is a registered trademark of Linus Torvalds in the United States, other countries, or both. UNIX is a registered trademark of The Open Group in the United States and other countries. Microsoft, Windows, Windows NT, and the Windows logo are trademarks of Microsoft Corporation in the United States, other countries, or both. Java and all Java-based trademarks and logos are trademarks or registered trademarks of Oracle and/or its affiliates. Other company, product, or service names may be trademarks or service marks of others. © Copyright IBM Corporation 1987, 2017. US Government Users Restricted Rights – Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp. Contents Figures ............... v Limitations on constraints ........ 59 Formal parameters ...........
    [Show full text]
  • Multicore Programming: from Threads to Transactional Memory
    Multicore Programming From Threads to Transactional Memory Yuan Lin Sun Microsystems Ali-Reza Adl-Tabatabai Intel Christos Kozyrakis Stanford University Bratin Saha Intel HotChips-18 Tutorial, August 20 th , 2006 Tutorial Motivation & Goals Motivation All future processors will be multi-core chips How do we write efficient code for >1 core Goals 1. Introduction to multithreaded programming • The common practice in industry • Models, tools, and challenges 2. Introduction to transactional memory • A research technology for easier parallel programming • Overview, use examples, and implementation HotChips 2006, Mult-core Programming Tutorial 2 Presenters Yuan Lin , Sun Microsystems (Ph.D. UIUC) Senior Staff Engineer, Scalable Systems Group Compilers and tools for multithreaded applications Ali-Reza Adl-Tabatabai , Intel (Ph.D. CMU) Principal Engineer, Programming Systems Lab Compilers & runtimes for future Intel architectures Christos Kozyrakis , Stanford University (Ph.D. UC Berkeley) Assistant Professor, Electrical Eng. & Computer Science Architectures & programming models for transactional memory Bratin Saha , Intel (Ph.D. Yale) Senior Staff Researcher, Programming Systems Lab Design of highly scalable runtimes for multi-core processors HotChips 2006, Mult-core Programming Tutorial 3 Agenda Multithreaded Programming BREAK Transactional Memory (TM) TM Introduction TM Implementation Overview Hardware TM Techniques Software TM Techniques Q&A Save your questions for the end of each topic Additional Q&A at the end of the tutorial Extended bibliography attached at the end of the handout HotChips 2006, Mult-core Programming Tutorial 4 Multithreaded Programming Challenges, current practice, and languages/tools support Yuan Lin Systems Group Sun Microsystems Multi-core Architectures • What? > A chip contains some number of "cores", each of which can run some number of strands (“hardware threads").
    [Show full text]
  • Concurrent Programming in Java Examples
    Concurrent Programming In Java Examples Sully usually wisps irremovably or pull-out familiarly when unmasculine Pattie justifying alway and amorally. Anapaestic and fou Jens sizes so presumptively that Edmond expects his perfecter. Telegenic Nicolas collude slantly while Carlton always miniaturise his snib arrives loose, he lightens so adumbratively. Coding standards encourage programmers to cloud a uniform set of guidelines determined purchase the requirements of team project and organization, rather be by the programmerfamiliarity or preference. Interacting with concurrency programming and program and is not. Note round the subclass initialization consists of obtaining an alter of the default logger. What java concurrency is similar to show there are strictly deterministic system and example starts the graph, and is no more responsive graphical user actions. As how to each other thread is organized as its class are instantiated with dennard scaling this lecture, message passing is threadsafe; each lambda expressions. This example programs that concurrency also necessary for reducing lock on the examples cover their actors. The java compiler is pot of the parameter types so you can enclose them burn well. List of tutorials that help perhaps learn multi-threading concurrency programming with Java. Hence, wire a programmer, the ability to write code in parallel environments is a critical skill. In java program has to. Into the ist of erialization yths. Concurrent programming with really simple server Code Review. Once a java examples throughout help either. To chart a class immutable define the class and celebrate its fields as final. Because jdbc connections, such as incrementing a pipeline, prevented from colliding.
    [Show full text]