The JVM-based version of ModelarDB in this repository is no longer being actively developed as it has been deprecated in favor of a significantly more efficient and user-friendly Rust-based implementation.

ModelarDB

ModelarDB is a modular model-based time series management system that interfaces a query engine and a data store with ModelarDB Core. This Core is a self-contained, adaptive, and highly extensible Java library for automatic online compression and efficient aggregation of time series. ModelarDB is designed for Unix-like operating systems and is tested on Linux.

ModelarDB intentionally does not gather usage data. So, all users are highly encouraged to post comments, suggestions, and bugs as GitHub issues, especially if a limitation of ModelarDB prevents it from being used in a particular domain.

Installation

1. Install a Java Development Kit*
2. Install the Scala Build Tool (sbt).
3. Clone the ModelarDB Git repository.
4. Start sbt in the root of the repository and run one of the following commands:

• compile compiles ModelarDB to Java class files.
• package compiles ModelarDB to a Jar file.
• assembly compiles ModelarDB to an uber Jar file.**
• run executes ModelarDB's main method.***
• test executes ModelarDB's unit and integration tests.****

* OpenJDK 11 and Oracle's Java SE Development Kit 11 have been tested.

** To execute ModelarDB on an existing Apache Spark cluster, an uber Jar must be created to ensure the necessary dependencies are included in a single Jar file.

*** If sbt run is executed directly from the command-line, then the run command and the arguments must be surrounded by quotes to pass the arguments to ModelarDB: sbt 'run arguments'

**** The data for the integration tests are read from Apache ORC files. The folder containing these files is retrieved from the environment variable MODELARDB_TEST_DATA_ORC. The integration tests may require additional memory which can be set through SBT_OPTS, e.g., SBT_OPTS="-Xmx8G" sbt test.

Configuration

ModelarDB requires that a configuration file is available at $HOME/.modelardb.conf or is passed as the first command-line argument. This file must specify the query processing engine and data store to use. An example configuration is included as part of this repository.

Documentation

For more information about using ModelarDB see the user manual.

Development

The repository is organized using two sets of branches:

• A master branch with the latest stable features and fixes.
• Multiple unstable feature branches with features currently in development. These are named dev/name-of-the-feature.

All changes are tracked in CHANGELOG.md and its unreleased section should be updated by commits that are added to the master branch.

Contributions

Contributions to all aspects of ModelarDB are highly appreciated and do not need to be in the form of code. For example, contributions can be:

• Helping other users.
• Writing documentation.
• Testing features and reporting bugs.
• Writing unit tests and integration tests.
• Fixing bugs in existing functionality.
• Refactoring existing functionality.
• Implementing new functionality.

Any questions or discussions regarding a possible contribution should be posted in the appropriate GitHub issue if one exists, e.g., the bug report if it is a bugfix, and as a new GitHub issue otherwise.

License

ModelarDB is licensed under version 2.0 of the Apache License and a copy of the license is bundled with the program.