INF 329 – Selected
                    topics in programming theory
                    Java Concurrency in
                              Practice
                      Chapters 10 and 11
                       Speaker: Guido Di Ridolfi
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                      Chapter 10
         “Avoiding Liveness Hazards”
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                              Intro
        • There is often a tension between safety and 
          liveness. We use locking to ensure thread 
          safety, but indiscriminate use of locking can 
          cause lock-ordering deadlocks.
        • This chapter explores some of the causes of 
          liveness failures and what can be done to 
          prevent them.
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                        10.1 - Deadlock
        • The following situation is the simplest case of 
           deadlock (or deadly embrace), where multiple 
           threads wait forever due to acyclic locking 
           dependency.
            • When thread A holds lock L and tries to acquire lock M, 
              but at the same time thread B holds M and tries to 
              acquire L, both threads will wait forever.
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