Improve performance by using Jprofile to study thread allocation and synchronization to uncover deadlock and data contention issues

Deadlock Example program: ThreadTest, which is a classic example of a deadlock that occurs with synchronous nesting;

 Public classThreadTest { Public StaticObject Lock1 =NewObject ();  Public StaticObject Lock2 =NewObject ();  Public Static voidmethod1 () {Trace ("Inside method1"); synchronized(lock1) {Trace ("Method1 got Lock1");            DoSomething (); synchronized(Lock2) {Trace ("Method1 got Lock2, sleeping");                DoSomething (); Trace ("Method1 Returning"); }        }    }     Public Static voidmethod2 () {Trace ("Inside method2"); synchronized(Lock2) {Trace ("Method2 got Lock2");            DoSomething (); synchronized(lock1) {Trace ("Method2 got Lock1, sleeping");                DoSomething (); Trace ("Method2 Returning"); }        }    }     Public Static voiddosomething () {Try{Thread.Sleep (5*1000); }        Catch(Interruptedexception x) {x.printstacktrace (); } Trace ("Waiking Up"); }     Public Static voidTrace (String msg) {System.out.println (Thread.CurrentThread ()+ " : " +msg); }     Public Static voidMain (string[] args)throwsException {NewThread (NewRunnable () { Public voidrun () {method1 ();        }}). Start (); NewThread (NewRunnable () { Public voidrun () {method2 ();    }}). Start (); }}

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You can see that two threads have been blocked;

To view the current lock view:

Right-click Export:

You can see the text description of the thread blocking situation;

Deadlock unlock cheats are to obtain the order of the locks to remain consistent;

Improve performance by using Jprofile to study thread allocation and synchronization to uncover deadlock and data contention issues