Summary
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Replace non-concurrent list array with a concurrent queue for session management in sunpkcs11.


Success Metric
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Increase the performance.


Motivation
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Performance did not scale as well as it could have using microbenchmarks on some hardware platform.

Description
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Session management in sunpkcs11 has been done with synchronized methods around an ArrayList which holds idle PKCS#11 session in a queue.  This queue exists to provide better performance by giving open and idle sessions to new crypto operations. Without a queue, opening and closing PKCS#11 session through JNI to the native PKCS#11 library after each crypto operation would be CPU expensive.

The change is to modernize this queue by using a concurrent class, ConcurrentLinkedDeque, and an AtomicInteger as a session counter.  This leaves the locking solely in the queue where it is performed better, and releases five methods from being bottlenecked in synchronized locks.

Testing
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Used provided test tool in JDK-7107611, no other testing is required.