These release notes cover new developer and user-facing incompatibilities, important issues, features, and major improvements.
SerializationFactory now uses the current context ClassLoader allowing for user supplied Serialization instances.
Simulated Datanodes should not include blocks that are still being written in their block report.
Checksum verification was mistakenly disabled for LocalFileSystem.
Checksum input stream can sometimes return invalid data to the user.
Changed bytes_read, bytes_written to type long to prevent metrics overflow.