+1 Tommaso 2011/2/23 Alan Gates <ga...@yahoo-inc.com>
> I would like to call a vote on accepting Howl as an Incubator project. The > proposal is available at http://wiki.apache.org/incubator/HowlProposal. > You can see the discussion from the proposal thread at > http://tinyurl.com/5w7y9p9. > > Alan. > > ---------------------- > > Abstract > Howl is a table and storage management service for data created using > Apache Hadoop. > > > Proposal > The vision of Howl is to provide table management and storage management > layers for Apache Hadoop. This includes: > > • Providing a shared schema and data type mechanism. > • Providing a table abstraction so that users need not be concerned > with where or how their data is stored. > • Providing interoperability across data processing tools such as > Pig, Map Reduce, Streaming, and Hive. > > Background > Data processors using Apache Hadoop have a common need for table management > services. The goal of a table management service is to track data that > exists in a Hadoop grid and present that data to users in a tabular format. > Such a table management service needs to provide a single input and output > format to users so that individual users need not be concerned with the > storage formats that are chosen for particular data sets. As part of having > a single format, the data will need to be described by one type of schema > and have a single datatype system. > > Additionally, users should be free to choose the best tools for their use > cases. The Hadoop project includes Map Reduce, Streaming, Pig, and Hive, and > additional tools exist such as Cascading. Each of these tools has users who > prefer it, and there are use cases best addressed by each of these tools. > Two users on the same grid who need to share data should not be constrained > to use the same tool but rather should be free to choose the best tool for > their use case. A table management service that presents data in the same > way to all of the tools can alleviate this problem by providing interfaces > to each of the data processing tools. > > There are also a few other features a table management service should > provide, such as notification of when data arrives. > > A couple of developers at Yahoo! started the project. It is based on the > Hive MetaStore component. There is good amount of interest in such a service > expressed from Yahoo!, Facebook, LinkedIn, and, others. We are therefore > proposing to place Howl in the Apache incubator and to build an open source > community around it. > > > Rationale > There is a strong need for a table management service, especially for large > grids with petabytes of data, and where the data volume is increasing by the > day. Hadoop users need to find data to read and have a place to store their > data. Currently users must understand the location of data to read, the > storage format, compression techniques used, etc. To write data they need to > understand where on HDFS their data belongs, the best compression format to > use, how their data should be serialized, etc. > > Most users do not want to be concerned with these issues. They want these > managed for them. > > Having it as an Apache Open Source project will highly benefit Howl from > the point of view of getting a large community that currently uses Hadoop > and the other products built around Hadoop (like Pig, Hive, etc.). Users of > the Hadoop ecosystem can influence Howl’s roadmap, and contribute to it. > Looking at it in another way, we believe having Howl as part of the Hadoop > ecosystem will be a great benefit to the current Hadoop/Pig/Hive community > too. > > > Current Status > > Meritocracy > Our intent with this incubator proposal is to start building a diverse > developer community around Howl following the Apache meritocracy model. We > have wanted to make the project open source and encourage contributors from > multiple organizations from the start. We plan to provide plenty of support > to new developers and to quickly recruit those who make solid contributions > to committer status. > > > Community > Howl is currently being used by developers at Yahoo! and there has been an > expressed interest from LinkedIn and Facebook. Yahoo! also plans to deploy > the current version of Howl in production soon. We hope to extend the user > and developer base further in the future. The current developers and users > are all interested in building a solid open source community around Howl. > > To work towards an open source community, we have started using the GitHub > issue tracker and mailing lists at Yahoo! for development discussions within > our group. > > > Core Developers > Howl is currently being developed by four engineers from Yahoo! - Devaraj > Das, Ashutosh Chauhan, Sushanth Sowmyan, and Mac Yang. All the engineers > have deep expertise in Hadoop and the Hadoop Ecosystem in general. > > > Alignment > The ASF is a natural host for Howl given that it is already the home of > Hadoop, Pig, HBase, Cassandra, and other emerging cloud software projects. > Howl was designed to support Hadoop from the beginning in order to solve > data management challenges in Hadoop clusters. Howl complements the existing > Apache cloud computing projects by providing a unified way to manage data. > > > Known Risks > > Orphaned Products > The core developers plan to work full time on the project. There is very > little risk of Howl getting orphaned since large companies like Yahoo! are > planning to deploy this in their production Hadoop clusters. We believe we > can build an active developer community around Howl (companies like Facebook > and LinkedIn have also expressed interest). > > > Inexperience with Open Source > All of the core developers are active users and followers of open source. > Devaraj Das is an Apache Hadoop committer and Apache Hadoop PMC member, and > has experience with the Apache infrastructure and development process. > Ashutosh Chauhan is an Apache Pig committer and Apache Pig PMC member. > Sushanth Sowmyan and Mac Yang made contributions to the Apache Hive and the > Apache Chukwa projects. > > > Homogeneous Developers > The current core developers are all from Yahoo! However, we hope to > establish a developer community that includes contributors from several > corporations, and we are starting to work towards this with Facebook and > LinkedIn. > > > Reliance on Salaried Developers > Currently, the developers are paid to do work on Howl. However, once the > project has a community built around it, we expect to get committers and > developers from outside the current core developers. Companies like Yahoo! > are invested in Howl being a solution to the data management problem in > Hadoop clusters, and that is not likely to change. > > > Relationships with Other Apache Products > Howl is going to be used by users of Hadoop, Pig, and Hive. See section > Initial Source below for more information about Howl's relationship to Hive. > > > An Excessive Fascination with the Apache Brand > While we respect the reputation of the Apache brand and have no doubts that > it will attract contributors and users, our interest is primarily to give > Howl a solid home as an open source project following an established > development model. We have also given reasons in the Rationale and Alignment > sections. > > > Documentation > Information about Howl can be found at http://wiki.apache.org/pig/Howl. > The following sources may be useful to start with: > > • > The GitHub site: https://github.com/yahoo/howl > > • > The roadmap: http://wiki.apache.org/pig/HowlJournal > > > Initial Source > Howl has been under development since Summer 2010 by a team of engineers in > Yahoo!. It is currently hosted on GitHub under an Apache license at > https://github.com/yahoo/howl. > > The initial development of Howl has consisted of: > > • maintaining a branch of the entire Hive codebase > • getting Howl-related patches committed to Hive > • developing Howl-specific plugins and wrappers to customize Hive > behavior > At runtime, Howl executes Hive code for metastore and CLI+DDL, disabling > anything related to Hadoop map/reduce execution. It also makes use of the > RCFile storage format contained in Hive. > > This approach was taken as a first step in order to validate the required > functionality and get a production version working. However, in the > long-term, maintaining a clone of Hive is undesirable. One possible > resolution is to factor the metastore+CLI+DDL components out of Hive and > move them into Howl (making Hive dependent on Howl). Another possible > resolution is to remove the copy of Hive from Howl and do the build/release > engineering necessary to make Howl depend on Hive. As part of the incubation > process, we plan to work towards resolution of these issues. > > > External Dependencies > The dependencies all have Apache compatible licenses. > > > Cryptography > Not applicable. > > > Required Resources > > Mailing Lists > • howl-private for private PMC discussions (with moderated > subscriptions) > • howl-dev > • howl-commits > • howl-user > > Subversion Directory > https://svn.apache.org/repos/asf/incubator/howl > > > Issue Tracking > JIRA Howl (HOWL) > > > Other Resources > The existing code already has unit tests, so we would like a Hudson > instance to run them whenever a new patch is submitted. This can be added > after project creation. > > > Initial Committers > • Devaraj Das > • Ashutosh Chauhan > • Sushanth Sowmyan > • Mac Yang > • Paul Yang > • Alan Gates > A CLA is already on file for Sushanth. > > > Affiliations > • Devaraj Das (Yahoo!) > • Ashutosh Chauhan (Yahoo!) > • Sushanth Sowmyan (Yahoo!) > • Mac Yang (Yahoo!) > • Paul Yang (Facebook) > • Alan Gates (Yahoo!) > > Sponsors > > Champion > Owen O’Malley > > > Nominated Mentors > • Olga Natkovich (Pig PMC member and Apache VP for Pig) > • Alan Gates (Pig PMC member) > • John Sichi (Hive PMC member) > > Sponsoring Entity > We are requesting the Incubator to sponsor this project. > --------------------------------------------------------------------- > To unsubscribe, e-mail: general-unsubscr...@incubator.apache.org > For additional commands, e-mail: general-h...@incubator.apache.org > >
