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From Josh Elser <>
Subject Re: [VOTE] Accept Omid into the Apache Incubator
Date Thu, 24 Mar 2016 04:33:05 GMT
+1 (binding)

Daniel Dai wrote:
> Following the discussion earlier, I'm calling a vote to accept Omid as
> a new Incubator project.
> [ ] +1 Accept Omid into the Incubator
> [ ] +0 Indifferent to the acceptance of Omid
> [ ] -1 Do not accept Omid because ...
> The vote will be open for the next 72 hours.
> Thanks,
> Daniel
> = Omid Proposal =
> === Abstract ===
> Omid is a flexible, reliable, high performant and scalable ACID
> transactional framework that allows client applications to execute
> transactions on top of MVCC key/value-based NoSQL datastores
> (currently Apache HBase) providing Snapshot Isolation guarantees on
> the accessed data.
> === Proposal ===
> Omid is a flexible open-source transactional framework that provides
> ACID transactions with Snapshot Isolation guarantees on top of NoSQL
> datastores. In particular, the current codebase brings the concept of
> transactions to the popular Apache HBase datastore. Omid offers great
> performance, it is highly available, and scalable. Omid's current
> version is able to scale to thousands of clients triggering concurrent
> transactions on application data stored in HBase. Omid can scale
> beyond 100K transactions per second on mid-range hardware while
> incurring in a minimal impact on the speed of data access in the
> datastore. We’re currently experimenting with a prototype version that
> can improve the performance up to ~380K TPS.
> Omid has been publicly available as an open-source project in Github
> under Apache License Version 2.0 since 2011 [1]. During these years,
> it has generated certain interest in the open source community,
> especially since the public presentation of the first version in
> Hadoop Summit 2013 [2]. Currently the Github project has 241 Stars and
> 93 forks. Yahoo Inc. submits this proposal to the Apache Software
> Foundation with the aim to transfer the Omid project -including its
> source code and documentation- to Apache in order to start the build
> of a stable open source community around it.
> [1]
> [2] Omid presentation at Hadoop Summit 2013:
> === Background ===
> An Omid prototype was first released as an open-source project back in
> 2011. Inspired by Google Percolator [1], it offered a lock-free
> approach to transactions in NoSQL datastores (See [2]). However,
> during these years, the design of Omid has evolved significantly.
> Whilst the current open-sourced version maintains many aspects of the
> original implementation, it is the result of a major redesign of the
> first prototype released in 2011.
> Omid has now a more decentralized design that does not sacrifice the
> consistency and performance of the original version. The current
> design also enables Omid to scale to thousands of clients executing
> transactions concurrently on application data stored in HBase.
> Internally, Omid still utilizes a lock-free approach to support
> multiple concurrent clients. Its design also relies on a centralized
> conflict detection component, the TSO, which now resolves in an
> efficient manner writeset collisions among concurrent transactions
> without having to piggyback commit information to the clients. Another
> important benefit of Omid is that it doesn't require any modification
> of the underlying key-value datastore, HBase in this case. Moreover,
> the recently added high availability algorithm allows to eliminate the
> single point of failure represented by the TSO in those system
> deployments requiring a higher degree of dependability. Last but not
> least, the provided user API is very simple, mimicking transaction
> managers in the relational world: begin, commit, rollback.
> Omid is used internally at Yahoo. Sieve, Yahoo’s web-scale content
> management platform powering some of next-generation search and
> personalization products is using Omid as a transaction manager in its
> processing pipeline. Sieve essentially acts as a huge processing hub
> between content feeds and serving systems. It provides an environment
> for highly customizable, real-time, streamed information processing,
> with typical discovery-to-service latencies of just a few seconds. In
> terms of scale and availability, Omid’s new design was largely driven
> by Sieve’s requirements.
> At Yahoo, we are also making an effort to disseminate the current
> status of the project through blog entries (See [3], [4] and [5]) and
> submissions to technical and academic conferences such as ATC 2016,
> Hadoop Summit 2016, HBaseConf 2016. Last but not least, Omid also
> appeared in a TechCrunch article in the last quarter of 2015 (See [6])
> [1] D. Peng and F. Dabek, Large-scale Incremental Processing Using
> Distributed Transactions and Notifications. USENIX Symposium on
> Operating Systems Design and Implementation, 2010
> [2] D. Gomez-Ferro, F. Junqueira, I. Kelly, B. Reed, and M. Yabandeh.
> Omid: Lock-free transactional support for distributed data stores. In
> Proc. of ICDE, 2013.
> [3]
> [4]
> [5]
> [6]
> === Rationale ===
> Programming with ACID (Atomicity, Consistency, Isolation, Durability)
> transactions is very popular and it is featured in relational
> databases. However, in the Big Data ecosystem, applications typically
> use NoSQL datastores, which do not provide ACID transactions. Such
> NoSQL datastores used to give up transactional support for greater
> agility and scalability. However, while early NoSQL data store
> implementations did not include transaction support, the need for
> transactions soon emerged in Big Data applications when accessing
> shared data; for  example, transactions are very important  for
> modern, scalable systems that process content incrementally.
> NoSQL datastores -including HBase- don’t provide transactional
> frameworks to coordinate the access to the underlying data for
> preserving consistency. By using Omid, Big Data applications that need
> to bundle multiple read and write operations on HBase into logically
> indivisible units of work can execute transactions with ACID
> properties, just as they would use transactions in the relational
> database world. Omid extends the HBase key-value access APl with
> transaction semantics. It can be exercised either directly, or via
> higher level data management API’s. For example, Apache Phoenix
> (SQL-on-top-of-HBase) might use Omid as its transaction management
> component.
> The following features make Omid an attractive choice for system
> designers and other projects in the Apache community:
> * Semantics. Omid implements Snapshot Isolation (SI,) supported by
> major SQL and NoSQL technologies (e.g. Google Percolator).
> * Performance and Scalability. Omid  provides a highly scalable,
> lock-free implementation of SI. To the best of our knowledge, it is
> also one of the few open source NoSQL transactional platforms that can
> execute more than 100K transactions per second [1]. A new prototype
> still in development can go even further, up to ~380K TPS.
> * Reliability.  Omid has a high-availability (HA) mode, in which the
> core service performing writeset conflict resolution operates as
> primary-backup process pair with automatic failover. The HA support
> has zero overhead on the mainstream operation.
> * Adaptability. Omid current version provides transactions on data
> stored in Apache HBase. However, Omid’s components are generic enough
> to be adapted to any other key-value NoSQL datasource that supports
> * Development. Omid provides a very simple interface that mimics
> standard HBase APIs, making it developer friendly. Only minimal
> extensions to the standard interfaces have been introduced to enable
> transactions.
> * Simplicity. Omid leverages the HBase infrastructure for managing its
> own metadata. It entails no additional services apart from those
> provided and used by HBase.
> * Track Record. As we have mentioned, Omid is already in use by
> very-large-scale production systems at Yahoo. Also, Hortonworks is
> integrating Omid in a metastore implementation for Hive based on
> HBase.
> [1] See also Haeinsa:
> === Current Status ===
> Current Omid implementation is available in both, Yahoo’s internal
> Github repository for internal use at Yahoo as well as in Yahoo’s
> Github public repository ( Both
> repositories are managed by Omid’s current developers at Yahoo.
> As it is mentioned above, Yahoo is currently using Omid for providing
> transactions in Sieve, a web-scale content management platform that
> powers Yahoo’s next-generation search and personalization products.
> ==== Meritocracy ====
> The first version of Omid was originally created in 2011 by Maysam
> Yabandeh, Daniel Gomez-Ferro, Ivan B. Kelly, Benjamin Reed and Flavio
> Junqueira at the R&D Scalable Computing Group of Yahoo Labs in Spain.
> During the years after its inception, Omid has matured to operate at
> Web scale and has been used internally by strategic projects at Yahoo
> such as Sieve. The current base of committers belong to the Yahoo team
> that took over the initial Omid prototype and rewrote it to meet the
> high availability and scalability requirements of the Sieve project.
> This base of committers has recently incorporated Hortonworks members
> that helped in the Omid adaptation to HBase 1.x versions.
> With this initial committer base, we aim to form a larger community
> that can collaborate with new ideas over the current code base. This
> new community will run the project following the "Apache Way"
> ( Users and new contributors
> will be treated with respect and welcomed. To grow the community, we
> will encourage contributors to provide patches, review code, propose
> new features improvements, talk at conferences such as Hadoop Summit,
> HBaseCon, ApacheCon, etc. Committership and PMC membership will be
> offered according to meritocracy.
> ==== Community ====
> The public Yahoo Omid repository at Github currently has 241 Stars and
> 93 forks, which means that there is an important interest for the
> project in the open-source community, at least compared with other
> similar projects (See
> Recently, Hortonworks contributors to the Apache Hive project which
> are working on storing Hive metadata in HBase (Apache Jira HIVE-9452)
> manifested interest in using Omid. We started with them a fruitful
> collaboration that resulted in Omid supporting HBase 1.x versions.
> Salesforce is also interested in collaborating in doing a Proof of
> Concept for integrating Omid as a pluggable transaction manager in
> Apache Phoenix.
> Yahoo, Hortonworks and Salesforce participants will constitute the
> initial set of committers and mentors for the proposal.
> ==== Core Developers ====
> The core developers of Omid are all skilled software developers and
> research engineers at Yahoo Inc. and Hortonworks with years of
> experiences in their fields. At this moment, developers are
> distributed across U.S. and Israel. The aim is to incorporate more
> committers from different organizations and locations over time.
> The current set of developers include experienced committers from
> Apache HBase, Hive and Hadoop projects that have been working with us
> in the current codebase found in Github.
> Finally, some of the core developers are currently NOT affiliated with
> the ASF and would require new ICLAs to be filed.
> === Alignment ===
> Omid enhances with transactions the already successful Apache HBase
> datastore project. We have collaborated with other developers inside
> and outside Yahoo which are involved in the Apache HBase community, so
> we have had reliable feedback from them.
> Although Omid brings value into HBase, the design of the current
> version provides a general transaction scheme that can potentially be
> adapted to other MVCC key-value datastores such as Apache Cassandra.
> Apache Phoenix is also a potential target. Phoenix is a SQL layer on
> top of HBase that can potentially integrate Omid in order to provide
> the well-know concept of transactions to Phoenix-based applications.
> === Known Risks ===
> ==== Orphaned products ====
> Yahoo’s Research and Search organizations have been taking care of
> Omid development since the first prototype creation in 2011. Yahoo has
> a long history participating in open-source projects, and has been
> also a long time contributor to the Apache community. For example, in
> Apache, Yahoo is an important contributor in many projects in the
> Hadoop ecosystem such as HBase, Pig, Storm or YARN, and has also
> open-sourced other well-known projects outside Hadoop, such as
> Zookeeper or Bookkeeper. So it is in the best interest of Yahoo make
> Omid also a successful open-source Apache product. If this happens, we
> are sure that a larger community will be formed around the project in
> a relatively short period of time, contributing to the diversification
> and stabilization of the base of committers.
> ==== Inexperience with Open Source ====
> This project has long standing experienced mentors and interested
> contributors from Apache HBase, Hive and Phoenix to help us moving
> through the open source process. We are actively working with
> experienced Apache community members to improve our project and
> further testing.
> ==== Homogeneous Developers ====
> Omid has been supported by Yahoo since its inception in 2011. However,
> all current committers are employed by their respective companies
> shown in the Affiliations section.
> ==== Reliance on Salaried Developers ====
> All the current developers are paid by their employers to contribute
> to this project. Yahoo developers will also continuing maintaining the
> internal Omid repository at their company.
> Of course, other developers are welcomed to contribute to this project
> after it is open sourced in Apache.
> ==== Relationships with Other Apache Product ====
> Current Omid incarnation serves transactional contexts to applications
> storing their data in HBase. However Omid design potentially allows to
> be adapted to serve transactions on top of other MVCC-based key-value
> datastores in Apache community such as Cassandra.
> As a transactional framework, many other Apache projects such as
> Apache Spark, Apache Phoenix, Apache Storm, Apache Flink could
> potentially benefit from Omid to get transactional contexts. In
> particular, Apache Phoenix -a SQL layer on top of HBase- might use
> Omid as its transaction management component. Once we open source Omid
> as an Apache project, we expect to generate more interest in the
> surrounded communities.
> Very recently, a new incubator proposal for a similar project called
> Tephra, has been submitted to the ASF. We think this is good for the
> Apache community, and we believe that there’s room for both proposals
> as the design of each of them is based on different principles (e.g.
> Omid does not require to maintain the state of ongoing transactions on
> the server-side component) and due to the fact that both -Tephra and
> Omid- have also gained certain traction in the open-source community.
> With regard to the Apache projects that Omid uses, apart from HBase,
> Omid relies on Apache Zookeeper and Curator projects in order to
> coordinate the (re)connection of transaction managers (acting as
> clients) to the conflict resolution component for transactions (server
> side.) They’re also used in order to coordinate the master and backup
> replicas in high availability scenarios.
> ==== An Excessive Fascination with the Apache Brand ====
> We are applying to the Incubator process because we think that it is
> the logical next step for the  Omid project after we open-sourced the
> code in Github some years ago. Yahoo has a long-standing history of
> contributing to Apache projects. The developers and contributors
> understand the implications of making it an Apache project, and
> strongly believe that the growing community can benefit from the
> Apache environment, ecosystem, and infrastrastructure.
> === Documentation ===
> Current documentation about the project is available in the wiki of
> Omid’s Github repository: . It will
> be moved under if the project
> is accepted as an Apache Incubator.
> === Initial Source ===
> Initial source code is currently hosted in Github for general viewing
> and contribution:
> Omid source code is written in Java code (99%) mixed with some shell
> script (1%) in order to configure and trigger the execution of main
> components.
> The code will be moved to Apache if accepted as
> an Incubator project.
> === Source and Intellectual Property Submission Plan ===
> The current Omid License for the code published in Github is Apache
> 2.0. If Omid fulfills and passes the conditions for being an Incubator
> project in the ASF, the source code will be transitioned via the
> Software Grant Agreement onto the ASF infrastructure and in turn made
> available under the Apache License, version 2.0.
> === External Dependencies ===
> The required external dependencies that are not Apache projects are
> all Apache licenses or other compatible Licenses:
> Maven&  Maven plugins ( [Apache 2.0]
> JDK7 or OpenJDK 7 ( [Oracle or Openjdk JDK License]
> Google Guava v11.0.2 ( [Apache 2.0]
> Google Guice v3.0 ( [Apache 2.0]
> Testng v6.8.8  ( [Apache 2.0]
> SLF4J ( v1.7.7 [MIT License]
> Netty ( v3.2.6.Final [Apache 2.0]
> Google Protocol Buffers v2.5.0
> ( [BSD License]
> Mockito ( v1.9.5 [MIT License]
> LMAX Disruptor v3.2.0 ( [Apache 2.0]
> Coda Hale/ Dropwizard Metrics v3.0.1
> ( [Apache 2.0]
> C.Beust, JCommander v1.35 ( [Apache 2.0]
> Hamcrest v1.3 ( [BSD License]
> === Cryptography ===
> Omid project does not use cryptography itself. However, Apache HBase
> -the datastore on top of which Omid works in its current version- uses
> standard APIs and tools for SSH and SSL communication where necessary.
> === Required Resources ===
> We request that following resources be created for the project to use:
> ==== Mailing lists ====
> omid-private (moderated subscriptions)
> omid-commits (commit notification)
> omid-dev (technical discussions)
> ==== Git repository ====
> ==== Documentation ====
> ==== JIRA instance ====
> === Initial Committers ===
> * Daniel Dai, Hortonworks (daijy<AT>hortonworks<DOT>com)
> * Alan Gates, Hortonworks, (gates<AT>hortonworks<DOT>com)
> * Lars Hofhansl, Salesforce (larsh<AT>apache<DOT>org)
> * Flavio P. Junqueira, Confluent (fpj<AT>apache<DOT>org)
> * Igor Katkov (katkovi<AT>yahoo-inc<DOT>com)
> * Francis C. Liu (fcliu<AT>yahoo-inc<DOT>com)
> * Thejas Nair, Hortonworks (thejas<AT>hortonworks<DOT>com)
> * Francisco Perez-Sorrosal (fperez<AT>yahoo-inc<DOT>com)
> * Sameer Paranjpye (sparanjpye<AT>yahoo<DOT>com)
> * Ohad Shacham (ohads<AT>yahoo-inc<DOT>com)
> * James Taylor, Salesforce (jamestaylor<AT>apache<DOT>org>)
> === Additional Interested Contributors ===
> * Ivan Kelly (ivank<AT>apache<DOT>org)
> * Maysam Yabandeh (myabandeh<AT>dropbox<DOT>com)
> === Affiliations ===
> * Edward Bortnikov, Yahoo Inc.
> * Daniel Dai, Hortonworks
> * Flavio P. Junqueira, Confluent
> * Igor Katkov, Yahoo Inc.
> * Ivan Kelly, Midokura
> * Francis C. Liu, Yahoo Inc.
> * Sameer Paranjpye, Arimo
> * Francisco Perez-Sorrosal, Yahoo Inc.
> * Ohad Shacham, Yahoo Inc.
> * Maysam Yabandeh, Dropbox Inc.
> === Sponsors ===
> ==== Champion ====
> Daniel Dai, Hortonworks (daijy<AT>hortonworks<DOT>com)
> ==== Nominated Mentors ====
> Alan Gates, Hortonworks, (gates<AT>hortonworks<DOT>com)
> Lars Hofhansl, Salesforce (larsh<AT>apache<DOT>org)
> Flavio P. Junqueira, Confluent (fpj<AT>apache<DOT>org)
> Thejas Nair, Hortonworks (thejas<AT>hortonworks<DOT>com)
> James Taylor, Salesforce (jamestaylor<AT>apache<DOT>org>)
> ==== Sponsoring Entity ====
> Apache Incubator PMC
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