YARN-2604. Scheduler should consider max-allocation-* in conjunction with the largest node. (Robert Kanter via kasha)
HDFS-7420. Delegate permission checks to FSDirectory. Contributed by Haohui Mai.
YARN-2679. Add metric for container launch duration. (Zhihai Xu via kasha)
Update release date for 2.5.2
YARN-2669. FairScheduler: queue names shouldn't allow periods (Wei Yan via Sandy Ryza)
HDFS-7425. NameNode block deletion logging uses incorrect appender. Contributed by Chris Nauroth.
HDFS-7331. Add Datanode network counts to datanode jmx page. Contributed by Charles Lamb.
MAPREDUCE-5785. Derive heap size or mapreduce.*.memory.mb automatically. (Gera Shegalov and Karthik Kambatla via kasha)