dineshchitlangia commented on a change in pull request #764: HDDS-2294. Create a new HISTORY.md in the new repository. URL: https://github.com/apache/hadoop-ozone/pull/764#discussion_r403229029
########## File path: HISTORY.txt ########## @@ -0,0 +1,60 @@ +<!--- + Licensed to the Apache Software Foundation (ASF) under one or more + contributor license agreements. See the NOTICE file distributed with + this work for additional information regarding copyright ownership. + The ASF licenses this file to You under the Apache License, Version 2.0 + (the "License"); you may not use this file except in compliance with + the License. You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. +--> + +# History of Apache Hadoop Ozone project + +Ozone development is started on a feature branch of HDFS-7240 as part of the Apache Hadoop HDFS project. Based on the Jira information the first Ozone commit was the commit of [HDFS-8456 Ozone: Introduce STORAGE_CONTAINER_SERVICE as a new NodeType.](https://issues.apache.org/jira/browse/HDFS-8456) in the May of 2015. + +Ozone is an Object Store for Hadoop which is based on a lower level storage replication layer. This layer is called originally HDSL (Hadoop Distributed Storage Layer) and renamed later to HDDS (Hadoop Distributed Data Storage). + +This generic storage layer started be implemented under [HDFS-11118](https://issues.apache.org/jira/browse/HDFS-11118) together with a jScsi based block storage layer ("CBlock") introduced by [HDFS-11361](https://issues.apache.org/jira/browse/HDFS-11361). + +As a summary: + + * HDDS (earlier HDSL): replicate huge binary _containers_ between datanodes + * Ozone: provides Object Store semantics with the help of HDDS + * CBlock: provides mountable volumes with the help of the HDDS layer (based on iScsi protocol) + +In the beginning of the year 2017 a new poddling project is started inside [Apache Incubator](http://incubator.apache.org/): [Apache Ratis](https://ratis.apache.org/). Ratis is an embeddable RAFT protcol implementation it is which become the main corner stone of the consensus inside Ozone/HDDS projects both (Started to [be used](https://issues.apache.org/jira/browse/HDFS-11519) by Ozone at March of 2017) + +In the October of 2017 a [discussion](https://lists.apache.org/thread.html/3b5b65ce428f88299e6cb4c5d745ec65917490be9e417d361cc08d7e@%3Chdfs-dev.hadoop.apache.org%3E) has been started on hdfs-dev mailing list to merge the existing functionality to the Apache Hadoop trunk. After a long debate Owen O'Malley [suggested a consensus](https://lists.apache.org/thread.html/c85e5263dcc0ca1d13cbbe3bcfb53236784a39111b8c353f60582eb4@%3Chdfs-dev.hadoop.apache.org%3E) to merge it to the trunk but use separated release cycle: + + > * HDSL become a subproject of Hadoop. + > * HDSL will release separately from Hadoop. Hadoop releases will notcontain HDSL and vice versa. + > * HDSL will get its own jira instance so that the release tags stay separate. + > * On trunk (as opposed to release branches) HDSL will be a separate module in Hadoop's source tree. This will enable the HDSL to work on their trunk and the Hadoop trunk without making releases for every change. + > * Hadoop's trunk will only build HDSL if a non-default profile is enabled. When Hadoop creates a release branch, the RM will delete the HDSL module from the branch. + > * HDSL will have their own Yetus checks and won't cause failures in the Hadoop patch check. Review comment: NIT: their -> its ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org With regards, Apache Git Services --------------------------------------------------------------------- To unsubscribe, e-mail: ozone-issues-unsubscr...@hadoop.apache.org For additional commands, e-mail: ozone-issues-h...@hadoop.apache.org
