Slide 1Slide 2Slide 3Slide 4Slide 5Slide 6Slide 7Slide 8Slide 9Multithreading9-12-2011Opening DiscussionMinute essay commentsMaps and Buffers in projects.Analysis is required for this project.MotivationThe future is parallel.Core counts are growing but clock speed isn't and neither is single thread performance.Software developers are behind the curve on this.Basic ApproachYou can use the java.lang.Thread class to represent a thread.Pass it a new Runnable that you define a run method in and call start to make it go.This makes it very easy to start new threads, but there are significant pitfalls when mutable memory is involved.joinThe join method of Thread will block until that thread has finished working.This is something you can do when you want a computation to continue only after each of the threads has completed.This only works if you are completely done with those threads.SynchronizationThreads use shared memory and you don't get significant control over what happens when.Race conditions are errors that occur because of dependence on timing details.Bank example.You can synchronize on objects to make sure critical blocks aren't accessed in parallelobj.synchronized { … }Slow and can cause deadlock.wait/notifyAllAllows synchronization between threads. A thread can wait and it won't restart until another thread notifies it.Put wait in while loop that checks boolean.Always use notifyAll instead of notify. Failure to do so leads to deadlocks.CodeI want to get commands working so that we can play with some of this in the drawing program.Minute EssayHow many cores does your computer have? Have you ever tried to keep them all busy?The next IcP is
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