The HBase team is happy to announce the immediate availability of Apache HBase 2.0.0-alpha-3.
Apache HBase is an open-source, distributed, versioned, non-relational database. Apache HBase gives you low latency random access to billions of rows with millions of columns atop non-specialized hardware. To learn more about HBase, see https://hbase.apache.org/. hbase-2.0.0-alpha-3 is a rough cut ('alpha'), not-for-production preview of what hbase-2.0.0 will look like. It is meant for devs and downstreamers to test drive and flag us early if we messed up anything ahead of our rolling GAs. hbase-2.0.0-alpha-3 is our third alpha release on our march toward an hbase-2.0.0. It includes all that was in previous alphas (new assignment manager, offheap read/write path, in-memory compactions, etc.), but had a focus on polishing our public API: old API that had been deprecated since hbase-1.0.0 or before was purged and new API was added with sympathetic deprecation of the previous. Along the Admin plane, incompatible changes were unavoidable; you will not be able to administer a hbase2 cluster using an hbase1 client (see dev-list "[DISCUSS] hbase-2.0.0 compatibility expectations" thread for discussion and see [1] for current list of Incompatibles). What is here will be our public API for 2.0.0 unless we get pushback from our gracious downstreamers. Alpha-3 does not have the final version of our Coprocessor API. Finishing the Coprocessor API for hbase-2.0.0 is the topic of our last planned alpha, 2.0.0-alpha-4. The Coprocessor API changes pretty radically in hbase-2.0.0 (though Coprocessor Endpoints will continue to work across an upgrade). See [2] for why and why it was unavoidable. Input now from Coprocessor API users before alpha-4 would be especially effective. The list of features addressed in 2.0.0 so far can be found here [3]. There are about 2700+. The list of ~500 fixes in 2.0.0 exclusively can be found here [4]. We've updated our overview doc. on the state of 2.0.0 [6] but JIRA 2.0.0 label [5] has undergone extensive weeding and presents a fairly good picture on what is yet to do before we 2.0.0. Check it out. Please take it for a spin and let us know if there is anything you would have us change or anything you see missing by mailing dev@hbase.apache.org or by filing issues at https://issues.apache.org/jira/projects/HBASE/summary We are planning one more alpha release before we move to beta (the above mentioned alpha-4). Now is the time to catch the egregious and flag the incompatibilities while we have time to bend. Once we move to beta, APIs and feature-set will be fixed. Download through an ASF mirror near you: https://www.apache.org/dyn/closer.lua/hbase/2.0.0-alpha-3 Checksums can be found here: https://www.apache.org/dist/hbase/2.0.0-alpha-3/hbase-2.0.0-alpha3-bin.tar.gz.md5 https://www.apache.org/dist/hbase/2.0.0-alpha-3/hbase-2.0.0-alpha3-src.tar.gz.md5 Project member signature keys can be found at https://www.apache.org/dist/hbase/KEYS PGP signatures are here: https://www.apache.org/dist/hbase/2.0.0-alpha-3/hbase-2.0.0-alpha3-src.tar.gz.asc https://www.apache.org/dist/hbase/2.0.0-alpha-3/hbase-2.0.0-alpha3-bin.tar.gz.asc For instructions on verifying ASF release downloads, please see https://www.apache.org/dyn/closer.cgi#verify Known issues are: + The LoadTestTool does not work (HBASE-18832). + MapReduce may fail for you (HBASE-18803 Mapreduce job get failed caused by NoClassDefFoundError: org/apache/commons/lang3/ArrayUtils.) Question, comments, and problems are always welcome at: dev@hbase.apache.org. Yours, The HBase Dev Team 1. Current list of Incompatibles: https://docs.google.com/document/d/1WCsVlnHjJeKUcl7wHwqb4z9iEu_ktczrlKHK8N4SZzs/edit#heading=h.723jjn18p2jr 2. Why CPs are Incompatible: https://docs.google.com/document/d/1WCsVlnHjJeKUcl7wHwqb4z9iEu_ktczrlKHK8N4SZzs/edit#heading=h.9k7mjbauv0wj 3. goo.gl/Gcrp4f 4. goo.gl/xHE7fF 5. https://issues.apache.org/jira/projects/HBASE/versions/12327188 6. https://docs.google.com/document/d/1WCsVlnHjJeKUcl7wHwqb4z9iEu_ktczrlKHK8N4SZzs/