Bundle Basics

A Peel bundle packages together the configuration data, datasets, and programs required for the execution of a particular set of experiments.

Folder Structure

The top-level elements of a Peel bundle are shortly summarized below.

Default Path Config Parameter Fixed Description
./apps app.path.apps Yes Workload applications.
./config app.path.config Yes Environment configurations and experiments definitions.
./datagens app.path.datagens No Data generators.
./datasets app.path.datasets No Static datasets.
./downloads app.path.downloads No Archived system binaries.
./lib app.path.log Yes Peel libraries and dependencies.
./log app.path.log Yes Peel execution logs.
./results app.path.results No State and log data from experiment runs.
./systems app.path.systems No Contains all running systems.
./utils app.path.utils No Utility scripts and files.
./peel.sh app.path.cli Yes The Peel command line interface.

You can customize the default paths of non-fixed paths in your bundle- or host-specific configuration. For more information how to do this, please refer to the Environment Configurations section.


The entries in the above list can be principally grouped as follows.

Peel CLI and Logs

The Peel command line tool. Invoke it without arguments to see the list of supported commands. While running, the Peel CLI spawns and executes OS processes. In the log folder, you will find the stdout and stderr output of these processes, as well as a copy of the actual console output produced by Peel itself.

Configurations and Definitions

The config folder contains *.conf files written in HOCON syntax which define the environment configuration, as well as *.xml files with the actual experiments defined as Spring beans.

Workload Applications

The apps folder contains the binaries of the experiment workload applications.

Data Sets and Generators

The datasets folder contains static, fixed-sized datasets required for the experiments. The datagens folder contains programs for dynamic generation of scalable datasets required for the experiments.


The downloads folder contains system binary archives for the systems in your experiment environment managed by Peel. The system archives are per default extracted in the systems folder.


The results folder contains data collected from attempted successful Peel experiment runs in a hierarchy following a ${suite}/${expName}.run${NN} naming convention.


The utils folder contains utility scripts (e.g., SQL queries and gnuplot scripts) that can be used next to or in conjunction with Peel CLI commands.


Taking a closer look at the peel-wordcount bundle from the Motivation section, we can see the following project and folder structure.

Bundle Sources

The bundle sources are organized as a multi-module Maven project with the following structure:

# cd "$BUNDLE_SRC" && \
# tree -L 1 --dirsfirst -d peel-wordcount
peel-wordcount                     # parent module
├── peel-wordcount-bundle          # module for bundle assembly
├── peel-wordcount-datagens        # module for data generators
├── peel-wordcount-flink-jobs      # module for Flink jobs 
├── peel-wordcount-peelextensions  # module for Peel extensions
└── peel-wordcount-spark-jobs      # module for Spark jobs

Assembled Bundle

The assembled bundle for the peel-wordcount bundle looks as follows:

# cd "$BUNDLE_BIN" && \
# tree -L 2 --dirsfirst peel-wordcount
├── apps
│   ├── peel-wordcount-flink-jobs-1.0-SNAPSHOT.jar
│   └── peel-wordcount-spark-jobs-1.0-SNAPSHOT.jar
├── config
├── datagens
│   └── peel-wordcount-datagens-1.0-SNAPSHOT.jar
├── datasets
├── downloads
├── lib
│   ├── ...
│   ├── peel-core-1.0-SNAPSHOT.jar
│   ├── peel-extensions-1.0-SNAPSHOT.jar
│   ├── peel-wordcount-peelextensions-1.0-SNAPSHOT.jar
│   └── ...
├── log
├── results
├── systems
├── utils
├── peel.sh

Here is how the Maven modules from the bundle sources are mapped to the assembled bundle.

  • The apps folder contains the jar artifacts for all *-jobs and *-apps modules.
  • The datagens folder contains the jar artifacts for all *-datagens modules.
  • The lib folder contains the two common Peel artifacts peel-core and peel-extensions, as well as the *-peelextensions artifact where the user can put hers bundle-specific Peel extensions.
  • The contents of the remaining folders are copied from the corresponding folder located under peel-wordcount-bundle/src/main/resources.


To assemble the bundle from the sources with Maven, you have one of four options:

mvn clean package       # package in peel-wordcount-bundle
mvn clean package -Pdev # package with soft links
mvn clean deploy        # package and copy to $BUNDLE_BIN
mvn clean deploy -Pdev  # package and copy with soft links

Running the deploy phase automatically copies the assembled bundle binaries folder to $BUNDLE_BIN.

Activating the dev profile (with -Pdev) enforces certain folders in the assembled bundle binaries (config, datasets, and utils) to be created as soft links to their corresponding source locations.