+1 (non-binding) Regards Ram
-----Original Message----- From: Andrew Purtell [mailto:andrew.purt...@gmail.com] Sent: Friday, March 4, 2016 11:55 AM To: general@incubator.apache.org Subject: Re: [VOTE] Accept Tephra into the Apache Incubator +1 (binding) > On Mar 3, 2016, at 5:29 PM, Poorna Chandra <poo...@apache.org> 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. --------------------------------------------------------------------- To unsubscribe, e-mail: general-unsubscr...@incubator.apache.org For additional commands, e-mail: general-h...@incubator.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: general-unsubscr...@incubator.apache.org For additional commands, e-mail: general-h...@incubator.apache.org
