HDFS-6487. TestStandbyCheckpoint#testSBNCheckpoints is racy. Contributed by Mit Desai.

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HDFS-6497. Make TestAvailableSpaceVolumeChoosingPolicy deterministic (cmccabe)

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YARN-2122. In AllocationFileLoaderService, the reloadThread should be created in init() and started in start(). (Robert Kanter via kasha)

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YARN-2128. FairScheduler: Incorrect calculation of amResource usage. (Wei Yan via kasha)

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