by Andrew Purtell, the 0.98.0 Release Manager
Apache HBase 0.98.0 is now available for download from the Apache mirrors and its artifacts are available in the Apache Maven repository.
HBase 0.98.0 is the next major release after HBase 0.96.
This release includes several new security features like cell visibility labels, cell ACLs, and transparent server side encryption. Please see the Security section of the HBase Online Manual for more information. There are significant performance improvements, such as a change to the write ahead log threading model that provides higher transaction throughput under high load, reverse scanners, MapReduce over snapshot files, and striped compaction. The complete list of changes in this release can be found in the release notes.
HBase 0.98 is expected to be wire compatible with HBase 0.96, so clients and servers mixed between these versions will seamlessly interoperate, provided new features available in 0.98 are not enabled. However, the HBase 0.98.0 release is not intended to be binary compatible at the Java API level with any HBase 0.96 release or earlier. You may need to recompile applications which reference the HBase JARs. Users of HBase 0.94 will have to perform an offline data migration procedure during upgrade. Consult the HBase Online Manual for more information. It is not necessary to migrate data from 0.94 to 0.98 through 0.96, you can upgrade from 0.94 to 0.98 directly if desired following the same procedure for upgrading from 0.94 to 0.96.
Thanks to all who contributed to this release!