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From Alan Gates <>
Subject [VOTE] Accept Stratosphere into the incubator
Date Thu, 10 Apr 2014 17:42:47 GMT
Based on the results of the discussion thread (
in particular notice the discussion on name change in the disucssion ), I would like to call
a vote on accepting Stratosphere into the incubator.

[ ] +1 Accept Stratosphere into the Incubator
[ ] +0 Indifferent to the acceptance of Stratosphere
[ ] -1 Do not accept Stratosphere because …

The vote will be open until Monday April 14 18:00 UTC.

= Stratosphere =
== Abstract ==
Stratosphere is an open source system for parallel data analysis. Stratosphere deeply integrates
MapReduce and database technologies to provide expressive and optimizable programming interfaces
and at the same time efficient and scalable execution.

== Proposal ==
Stratosphere is an open source system for expressive, declarative, fast, and efficient data
analysis. Stratosphere combines the scalability and programming flexibility of distributed
MapReduce-like platforms with the efficiency, out-of-core execution, and query optimization
capabilities found in parallel databases.

== Background ==
There is currently a need for general-purpose cluster computing platforms that are compatible
with the Hadoop ecosystem, are more efficient, easier to use, and can support more applications
than Hadoop MapReduce, but are not restricted to a specific data model and language (such
as the relational model and a variant of SQL). Stratosphere fulfils these needs.

Stratosphere exposes expressive APIs in Java and Scala (conceptually similar to Spark, Cascading,
Scalding) that allow arbitrary user-defined functions in the same language and data model
that the program is written in. Stratosphere programs pass through a cost-based optimizer
that finds the best execution path for these programs depending on the data and cluster characteristics.
The design and implementation of Stratosphere is based on research that generalizes query
optimizers in relational databases. Stratosphere has a distributed runtime that is architected
upon the principles of parallel databases, providing true pipelining (a basis for stream processing)
and efficient out-of-core algorithms for grouping, sorting, joining, and aggregating data.
Stratosphere provides first-class support for iterative algorithms via a built-in iterate
operator, covering Machine Learning and graph analysis use cases. It achieves performance
similar to Apache Giraph without being a specialized graph processing system.

Stratosphere has undergone three major releases (v0.1, v0.2, v0.4) and some minor ones.

== Rationale ==
Stratosphere started out in 2008 as a research project by the Technical University of Berlin,
the Humboldt University of Berlin, and the Hasso Plattner Institute, and has received subsequent
funding from the German Research Council, the European Institute of Innovation and Technology,
the European Commision, and industry.

The traction of Stratosphere has by far exceeded our initial expectations, and we are therefore
seeking an organizational long-term home for Stratosphere beyond the University walls that
will house and further encourage contributors from companies and other organizations that
are interested in Stratosphere. We believe that the Apache Software Foundation is the ideal
home for Stratosphere. Stratosphere integrates with several existing Apache projects, such
as HDFS, YARN, HBase, and Avro. The team is familiar with the Apache processes and fully subscribes
to the Apache mission. One of the proposing members is a long-time Apache contributor and
PMC member.

== Initial Goals ==
 * Move the existing codebase to Apache
 * Integrate with the Apache development process
 * Ensure all dependencies are compliant with Apache License version 2.0
 * Incremental development and releases per Apache guidelines

== Current Status ==
=== Meritocracy ===
Stratosphere operated on meritocratic principles from the get go. The initial project proposal
submitted to the German Research Council in 2008 stated that all code developed in the project
will be released as open source under the Apache 2 license. Currently, all the discussions
pertaining to Stratosphere development are public on [[|GitHub]]
 and our [[!forum/stratosphere-dev|mailing list]]. The current
incubation proposal includes the major code contributors to Stratosphere. Several additional
people have worked on the Stratosphere codebase for research prototypes and industry use cases
and would be interested in becoming committers. We are starting with a small committer group
and we plan to add additional committers following an open merit-based decision process during
the incubation phase.

=== Community ===
Currently, the core of Stratosphere is developed at TU Berlin, mainly by the committers listed
in this proposal. Additional people from several Universities and companies in Europe are
working with Stratosphere and are interested in becoming committers to the project.

During the years, Stratosphere has been adopted as a platform for research and teaching in
several Universities (TU Berlin, HU Berlin, HPI, RWTH, Inria, KTH, U. Trento, UCSD, and others),
and it is currently witnessing its first industrial installations. We are seeing a rapidly
growing interest in Stratosphere by both startups and large companies, as well as a growing
community (our first [[|Stratosphere Summit]]
in November 2013 attracted over 80 participants). Stratosphere was recently accepted as a
mentoring organization in Google Summer of Code 2014.

We believe that acceptance in the Apache Software Foundation will consolidate the current
community under one organizational umbrella, and most importantly accelerate the growth of
the community.

=== Core developers ===
The core developers of the system are Stephan Ewen, Fabian Hueske, Daniel Warneke, Robert
Metzger, Ufuk Celebi, and Aljoscha Krettek, who are all committers in the current proposal.

=== Alignment ===
Stratosphere is compatible with, and related to several Apache projects. Stratosphere re-uses
parts of Apache Hadoop, in particular HDFS and YARN, as well as Apache HBase and Apache Avro.
Stratosphere is a very good compilation target for query languages such as Apache Hive and
Apache Pig.

== Known Risks ==
=== Orphaned Products ===
There is strong interest in Stratosphere by several companies and organizations, and there
is currently a long-term commitment to fund salaried developers for Stratosphere by public
and private organizations in Europe.

=== Inexperience with Open Source ===
Sebastian Schelter is a committer and PMC member of Apache Mahout and Apache Giraph, member
of the Apache Software Foundation, member of the Incubator PMC and project mentor for Apache
Drill. Sebastian, along with our mentors, will guide the rest of the committers that have
experience with releasing software as open source but little experience in participating in
an open source project besides Stratosphere itself.

In mid-2013 Stratosphere transitioned from an “open source project with publicly accessible
source code” to an open source project that puts the community first. We moved from a University-hosted
git repository to GitHub, where we discuss all issues publicly. This also includes release
planning (via GitHub’s milestone feature) and code reviews. We also moved our build system
to the publicly available Travis-CI. The mailing lists are hosted with Google Groups, we use
the public Maven repository infrastructure of Sonatype. The source code of the
website is publicly available and is meant to be changed by external contributors (for example
for documentation purposes).

=== Homogeneous Developers ===
Most committers in this proposal belong to the same institution (TU Berlin). The engagement
of these committers goes well beyond the necessary development to support research, and all
committers work on Stratosphere in their free time. Several people from other institutions
are working on and are familiar with the Stratosphere codebase. We will work to attract them
as future committers during the incubation phase, following a merit-based approach.

=== Reliance on Salaried Developers ===
Currently, Stratosphere receives support from salaried developers, in particular from graduate
students at TU Berlin that are funded by the German Research Council, the European Institute
of Technology, and the European Commission. These students work in their free time on Stratosphere
in addition to their employment.

We expect that Stratosphere development will occur on both salaried and volunteer time. We
will recruit additional committers, including non-salaried developers, and we will work to
ensure that the project will move forward independently of salaried developers.

=== Relationship with Other Apache Products ===
Stratosphere interfaces with several existing Apache projects: Apache HBase for storage, Apache
Hadoop (HDFS for storage, YARN for resource management, and Stratosphere contains a generic
wrapper for Hadoop MapReduce input formats), and Apache Avro (for serialization). Stratosphere
uses Apache Maven and Apache Commons libraries internally. Stratosphere can be a great compilation
target for Apache Pig and Apache Hive, although such functionality is not yet implemented.

Stratosphere is also related with several projects undergoing incubation in the Apache Incubation
project, such as Tez, Drill, and Spark (graduated). While all these projects target sufficiently
different spaces and have different architectures, it would be interesting to explore code
reuse possibilities. For example, we are currently basing our design for compiling SQL to
Stratosphere on the Optiq library, also used by Apache Drill.

=== An Excessive Fascination with the Apache Brand ===
We believe that the Apache brand will help us attract contributors to Stratosphere, by giving
us a well-defined, transparent development process under a known brand. At the same time,
Stratosphere already has a healthy community and current funding guarantees the further codebase
development and growth of the project for the next 3-5 years. The reason for this proposal
is not to gain publicity, but to further strengthen the longevity of the project as explained
in the Rationale section.

== Documentation ==
 * [[|Project website]]
 * [[|Documentation]]
 * [[|Codebase]]
 * [[!forum/stratosphere-dev|Mailing list]]

== Initial Source ==
Stratosphere is hosted on [[|GitHub]] . This is
the codebase that we will migrate to the Apache Foundation. The code was previously hosted
on a TU Berlin’s own git infrastructure. It has always been Apache 2.0 licensed.

=== Source and Intellectual Property Submission Plan ===
All initial and past committers will sign a CLA with the ASF while the incubator proposal
for Stratosphere is being discussed. All organizations that have employed Stratosphere contributors
in the past will sign a SGA. Current contributors will sign a CCLA. All major contributors
are still active in the project.

=== External Dependencies ===
All critical dependencies are, to the extend of our knowledge, from other Apache projects.
These include Apache Hadoop (for YARN and HDFS) and some libraries (log4j, commons codec,
junit and more). Our web frontend uses some MIT-licensed JavaScript libraries.

== Required Resources ==
=== Mailing list ===
We will migrate our mailing lists to the following:


=== Source control ===
We would like to use Git for source control and enable GitHib mirroring functionality, where
code reviews on GitHub are automatically forwarded to the developer mailing list. (See also:

=== Issue tracking ===
We are currently using GitHub for issue tracking. We request an Apache-hosted JIRA, and we
will import existing issues there.

== Initial committers ==
 * Stephan Ewen -
 * Fabian Hueske -
 * Daniel Warneke -
 * Robert Metzger -
 * Ufuk Celebi -
 * Aljoscha Krettek -
 * Kostas Tzoumas -
 * Sebastian Schelter  -

=== Affiliations ===
 * Stephan Ewen (TU Berlin)
 * Fabian Hueske (TU Berlin)
 * Daniel Warneke (Amadeus IT Group)
 * Robert Metzger (TU Berlin)
 * Ufuk Celebi (FU Berlin)
 * Aljoscha Krettek (TU Berlin)
 * Kostas Tzoumas (TU Berlin)
 * Sebastian Schelter (TU Berlin)

== Sponsors ==
=== Champion ===
Alan Gates ( )

=== Nominated Mentors ===
 * Sean Owen ( ) (Note: Sean is an Apache member but not currently on the
IPC, he will need to request IPMC membership)
 * Ted Dunning ( )
 * Owen O'Malley ( )
 * Henry Saputra ( )
 * Ashutosh Chauhan (

=== Sponsoring Entity ===
The Apache Incubator

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