+1 (non-binding) -Andreas.
On Fri, Mar 4, 2016 at 12:19 PM, Terence Yim <cht...@gmail.com> wrote: > +1 (non-binding) > > Terence > > On Fri, Mar 4, 2016 at 1:13 AM, Jean-Baptiste Onofré <j...@nanthrax.net> > wrote: > > > +1 (binding) > > > > Regards > > JB > > > > > > On 03/04/2016 02:29 AM, Poorna Chandra wrote: > > > >> Hi All, > >> > >> Tephra proposal was sent out for discussion last week. The proposal is > >> available at https://wiki.apache.org/incubator/TephraProposal > >> > >> Please vote to accept Tephra into the Apache Incubator. The vote will be > >> open for the next 72 hours. > >> > >> [ ] +1 Accept Tephra as an Apache Incubator podling. > >> [ ] +0 Abstain. > >> [ ] -1 Don’t accept Tephra as an Apache Incubator podling because ... > >> > >> Thanks, > >> Poorna. > >> > >> ------ > >> > >> = Abstract = > >> > >> Tephra is a system for providing globally consistent transactions on > >> top of Apache HBase and other storage engines. > >> > >> = Proposal = > >> > >> Tephra is a transaction engine for distributed data stores like Apache > >> HBase. > >> It provides ACID semantics for concurrent data operations that span over > >> region > >> boundaries in HBase using Optimistic Concurrency Control. > >> > >> = Background = > >> > >> HBase provides strong consistency with row- or region-level ACID > >> operations. However, it sacrifices cross-region and cross-table > >> consistency in favor of scalability. This trade-off requires application > >> developers to handle the complexity of ensuring consistency when their > >> modifications span region boundaries. By providing support for global > >> transactions that span regions, tables, or multiple RPCs, > >> Tephra simplifies application development on top of HBase, without a > >> significant impact on performance or scalability for many workloads. > >> > >> Tephra leverages HBase’s native data versioning to provide > multi-versioned > >> concurrency control (MVCC) for transactional reads and writes. > >> With MVCC capability, each transaction sees its own consistent > “snapshot” > >> of > >> data, providing snapshot isolation of concurrent transactions. > >> MVCC along with conflict detection and handling enables Optimistic > >> Concurrency > >> Control. > >> > >> Tephra consists of three main components: > >> * Transaction Server – maintains global view of transaction state, > >> assigns > >> new transaction IDs and performs conflict detection; > >> * Transaction Client – coordinates start, commit, and rollback of > >> transactions; and > >> * Transaction Processor Coprocessor – applies filtering to the data > >> read (based > >> on a given transaction’s state) and cleans up any data from old > >> (no longer visible) transactions. > >> > >> Although Tephra only supports HBase now, it can be extended to support > >> transactions on any store that has multi-versioning and rollback > >> support. The transactions > >> can span over multiple stores and storage paradigms. > >> > >> = Rationale = > >> > >> Tephra has simple abstractions which can be used by an application to > >> add transaction support over HBase. By abstracting away transaction > >> handling using Tephra, the application is freed of > >> transaction logic, and the application developer can focus on the use > >> case. > >> Also, Tephra can be extended to support transactions on data sources > other > >> than HBase. > >> > >> By making Tephra an Apache open source project, we believe that there > will > >> be wider adoption and more opportunities for Tephra to be integrated > >> into other Apache projects. > >> > >> = Current Status = > >> > >> Tephra was built at Cask Data Inc. initially as part of > >> open-source framework Cask Data Application Platform (CDAP) > >> [[http://cdap.io/]]. > >> It was later converted into an independent open source project with > >> Apache 2.0 License [[https://github.com/caskdata/tephra]]. > >> > >> Tephra is used in CDAP as the transaction engine. As part of CDAP, > Tephra > >> has been deployed at multiple companies. > >> > >> Apache Phoenix is using Tephra as transaction engine in the next > release. > >> > >> == Meritocracy == > >> > >> Our intent with this incubator proposal is to start building a diverse > >> developer community around Tephra following the Apache meritocracy > model. > >> Since Tephra was initially developed in early 2013, we have had fast > >> adoption and contributions within Cask Data. We are looking forward to > >> new contributors. We wish to build a community based on Apache's > >> meritocracy principles, working with those who contribute significantly > to > >> the project and welcoming them to be committers both during the > incubation > >> process and beyond. > >> > >> == Community == > >> > >> Core developers of Tephra are at Cask Data. Recently the developer > >> community > >> has expanded to include folks from Apache Phoenix. We hope to extend our > >> contributor base significantly and we will invite all who are interested > >> in working on distributed transaction engine. > >> > >> == Core Developers == > >> > >> A few engineers from Cask Data and outside have developed Tephra: > >> Andreas Neumann, Terence Yim, Gary Helmling, Andrew Purtell and > >> Poorna Chandra. > >> > >> > >> == Alignment == > >> > >> The ASF is the natural choice to host the Tephra project as its goal of > >> encouraging community-driven open source projects fits with our vision > for > >> Tephra. > >> > >> Additionally, many other projects with which we are familiar and expect > >> Tephra to integrate with, such as Phoenix, Zookeeper, HDFS, log4j, and > >> others > >> mentioned in the External Dependencies section are Apache projects, and > >> Tephra will benefit by close proximity to them. > >> > >> = Known Risks = > >> > >> == Orphaned Products == > >> > >> There is very little risk of Tephra being orphaned, as it is a key part > of > >> Cask Data’s products. The core Tephra developers plan to continue to > work > >> on Tephra, and Cask Data has funding in place to support their efforts > >> going forward. > >> Also with Phoenix using Tephra for transactions, Phoenix developers are > >> keen on contributing to Tephra. > >> > >> > >> == Inexperience with Open Source == > >> > >> Several of the core developers have experience with open source > >> development. Andreas Neumann is an Apache committer for Oozie and Twill. > >> Terence Yim is an Apache committer for Helix and Twill. Poorna Chandra > >> is an Apache committer for Twill. Gary Helmling is a committer for > >> Apache Twill and a committer and PMC member for Apache HBase. > >> James Taylor is PMC chair for Apache Phoenix, PMC member of Apache > >> Calcite, > >> and an IPMC member. > >> > >> == Homogeneous Developers == > >> > >> The current core developers are all Cask Data employees. However, we > >> intend to establish a developer community that includes independent and > >> corporate contributors. We are encouraging new contributors via our > >> mailing > >> lists, public presentations, and personal contacts, and we will continue > >> to > >> do so. > >> > >> Apache Phoenix developers have already contributed several patches to > >> Tephra, > >> and have expressed interest in becoming long term contributors. > >> > >> == Reliance on Salaried Developers == > >> > >> Currently, these developers are paid to work on Tephra. Once the project > >> has > >> built a community, we expect to attract committers, developers and > >> community > >> other than the current core developers. However, because Cask Data > >> products use Tephra internally, the reliance on salaried developers is > >> unlikely to change, at least in the near term. > >> > >> == Relationships with Other Apache Products == > >> > >> Tephra is deeply integrated with Apache projects. Tephra provides > >> transactions > >> over Apache HBase, and uses Apache Twill and Apache Zookeeper for > >> coordination. > >> A number of other Apache projects are Tephra dependencies, and are > >> listed in the External Dependencies section. > >> > >> In addition, Apache Phoenix is using Tephra as the transaction engine. > >> > >> == An Excessive Fascination with the Apache Brand == > >> > >> While we respect the reputation of the Apache brand and have no doubt > that > >> it will attract contributors and users, our interest is primarily to > give > >> Tephra a solid home as an open source project following an established > >> development model. We have also given additional reasons in the > Rationale > >> and Alignment sections. > >> > >> = Documentation = > >> > >> The current documentation for Tephra is at > >> https://github.com/caskdata/tephra. > >> > >> = Initial Source = > >> > >> Tephra codebase is currently hosted at > https://github.com/caskdata/tephra > >> . > >> > >> = Source and Intellectual Property Submission Plan = > >> > >> Tephra codebase is currently licensed under Apache 2.0 license. > >> Cask Data owns the trademark for "Tephra". As part of the incubation > >> process > >> Cask Data will transfer the trademark to Apache Foundation. > >> > >> = External Dependencies = > >> > >> The dependencies all have Apache-compatible licenses: > >> * dropwizard metrics (Apache 2.0) > >> * fastutil (Apache 2.0) > >> * gson (Apache 2.0) > >> * guava-libraries (Apache 2.0) > >> * guice (Apache 2.0) > >> * hadoop (Apache 2.0) > >> * hbase (Apache 2.0) > >> * hdfs (Apache 2.0) > >> * junit (EPL v1.0) > >> * logback (EPL v1.0 ) > >> * slf4j (MIT) > >> * thrift (Apache 2.0) > >> * twill (Apache 2.0) > >> * zookeeper (Apache 2.0) > >> > >> = Cryptography = > >> > >> Tephra does not use cryptography itself, however it can run on secure > >> Hadoop, > >> which uses Kerberos. > >> > >> = Required Resources = > >> > >> == Mailing Lists == > >> > >> * tephra-private for private PMC discussions (with moderated > >> subscriptions) > >> * tephra-dev for technical discussions among contributors > >> * tephra-commits for notification about commits > >> > >> == Subversion Directory == > >> > >> Git is the preferred source control system: git://git.apache.org/tephra > >> > >> == Issue Tracking == > >> > >> JIRA Tephra (TEPHRA) > >> > >> == 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 = > >> > >> * Andreas Neumann <anew at apache dot org> > >> * Terence Yim <chtyim at apache dot org> > >> * Poorna Chandra <poorna at apache dot org> > >> * Gokul Gunasekaran <gokul at cask dot co> > >> * James Taylor <jamestaylor at apache dot org> > >> * Thomas D'Silva <tdsilva at apache dot org> > >> * Gary Helmling <garyh at apache dot org> > >> > >> = Affiliations = > >> > >> * Andreas Neumann (Cask Data) > >> * Terence Yim (Cask Data) > >> * Poorna Chandra (Cask Data) > >> * Gokul Gunasekaran (Cask Data) > >> * James Taylor (Salesforce.com) > >> * Thomas D'Silva (Salesforce.com) > >> * Gary Helmling (Facebook) > >> > >> = Sponsors = > >> > >> == Champion == > >> > >> James Taylor <jamestaylor at apache dot org> (V.P., Apache Phoenix) > >> > >> == Nominated Mentors == > >> > >> * James Taylor <jamestaylor at apache dot org> > >> * Lars Hofhansl <larsh at apache dot org> > >> * Andrew Purtell <apurtell at apache dot org> > >> * Alan Gates <gates at apache dot org> > >> * Henry Saputra <hsaputra at apache dot org> > >> > >> == Sponsoring Entity == > >> > >> We are requesting that the Incubator sponsor this project. > >> > >> > > -- > > Jean-Baptiste Onofré > > jbono...@apache.org > > http://blog.nanthrax.net > > Talend - http://www.talend.com > > > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: general-unsubscr...@incubator.apache.org > > For additional commands, e-mail: general-h...@incubator.apache.org > > > > >
