This is the repository for the Load-Balancing Analysis Framework (LBAF)

It contains the following subdirectories:

• src: Load-Balancing Simulator code
• doc: Research papers and related documents
• data: Various data inputs or outputs
• tests: Unit tests and acceptance tests

Please refer to our documentation for more details.

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Table of Contents

• Getting Started
• Installation
• Testing
• Usage
• Additional Programs
• LBAF In Literature

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Getting Started

LBAF currently supports Python 3.8 - 3.11. You can download Python here.

Optional: Create a virtual environment (recommended in development)

To create and activate a virtual environment:

python -m venv venv
source venv/bin/activate

Note

You can create separate virtual environments for different development branches. For example, a Python 3.8 environment for branch 125 could be named venv38-branch-125. Within this environment, you can install lbaf as an editable package (see below).

Installation

LBAF can be installed in two ways:

1. Install the LBAF Package (recommended)

Users can easily install the latest release of LBAF with:

pip install lbaf

Developers should clone the repo and install the package in editable mode:

git clone [email protected]:DARMA-tasking/LB-analysis-framework.git
pip install -e LB-analysis-framework

2. Install Dependencies

If you do not wish to install LBAF as a package, simply clone the repo and install dependencies:

git clone [email protected]:DARMA-tasking/LB-analysis-framework.git
pip install -r LB-analysis-framework/requirements.txt

Testing

Begin by installing the test dependencies in requirements.txt.

pip install tox coverage pylint pytest anybadge

Then, to run all tests locally:

cd <project-path>
tox -e py<x>

where <x> is 38, 39, 310, or 311, depending on your Python version. For example, in an environment with Python 3.8: tox -e py38.

The tox command will:

• run all tests defined in tox.ini
• create the artifacts directory in main project path
• create an html coverage report and a pylint report within the artifacts directory

Usage

If the lbaf package is installed, LBAF can be run using the following command:

lbaf -c <config-file-path>

If dependencies were installed instead, LBAF must be run from source:

cd <project-path>
python src/lbaf/Applications/LBAF_app.py -c <config-file-path>

Configuration File

The configuration file is a YAML file that specifies how LBAF will run.

<config-file-path> can be an absolute path or a relative path to your configuration file.

A description of each parameter in the configuration file can be found here, and sample configurations can be found in the config directory.

Visualization

LBAF can optionally leverage vt-tv, a DARMA-tasking tool built off of VTK, to visualize the work-to-rank mappings, communications, and memory usage of a run.

To get started, you will need to build VTK (instructions here).

Then, clone the vt-tv repository and install the Python bindings:

git clone https://github.com/DARMA-tasking/vt-tv.git
VTK_DIR=/path/to/vtk/build pip install vt-tv

Once vt-tv has been installed, you may include visualization parameters in the configuration file. Sample parameters are found (commented out) at the bottom of config/conf.yaml.

For more instructions on building and using vt-tv, refer to the documentation.

Verbosity

To print a list of all Quantities of Interest (QOI) supported by LBAF, add a verbosity argument to the run command:

cd <project-path>
lbaf -c <config-file-name> -v <verbosity-level>

or

cd <project-path>
python src/lbaf/Applications/LBAF_app.py -c <config-file-name> -v <verbosity-level>

To output only the Rank QOI, use -v 1. Otherwise, to print both Rank and Object QOI, use -v 2.

Additional Programs

JSON data files validator

JSON data files Validator validates vt data files against defined schema. It is located in the vt repository and can be found here.

Download into LBAF

If the lbaf package is installed, run:

lbaf-vt-data-files-validator-loader

Otherwise, run from source:

cd <project-path>
python src/lbaf/Utils/lbsJSONDataFilesValidatorLoader.py

The script will be saved to <project-path>/src/lbaf/imported/JSON_data_files_validator.py

Run from LBAF

If the lbaf package is installed, run:

lbaf-vt-data-files-validator

Otherwise, run from source:

cd <project-path>
python src/lbaf/imported/JSON_data_files_validator.py

Note: This command automatically downloads the JSON_data_files_validator.py script if needed.

Usage

These commands assume that LBAF was installed as a package. When running from source, replace the run command as noted above.

For single file:

# With relative path
lbaf-vt-data-files-validator --file_path=../../../data/nolb-8color-16nodes-data/data.0.json

# With absolute path
lbaf-vt-data-files-validator --file_path=<project-path>/data/nolb-8color-16nodes-data/data.0.json

For many files in the same directory:

# With relative path
lbaf-vt-data-files-validator --dir_path=../../../data/nolb-8color-16nodes-data

# With absolute path
lbaf-vt-data-files-validator --dir_path=<project-path>/data/nolb-8color-16nodes-data

# Optionally one could pass --file_prefix and/or --file_suffix
# When one passes files with given prefix/suffix or both will be validated
# When no prefix and suffix will be given validator will find most common prefix and suffix in the directory
# and will use them for validation process
lbaf-vt-data-files-validator --dir_path=../../data/nolb-8color-16nodes-data --file_prefix=data --file_suffix=json

vt Data Extractor

The vt Data Extractor extracts phases from vt stats files.

Usage

To run using the lbaf package:

lbaf-vt-data-extractor

To run from source:

cd <project-path>
python src/lbaf/Utils/lbsVTDataExtractor.py

Input arguments

• input_data_dir: str - path to dir with files to extract e.g. "./data/<dir-with-files>"
• output_data_dir: str - path to dir where files should be saved e.g. "./output" (will be created when doesn't exist)
• phases_to_extract: list - list of phases [int or str] e.g. [0, 1, "2-4"] will extract phases [0, 1, 2, 3, 4]
• file_prefix: str - data file prefix e.g. if filename is stats.0.json, then prefix should be set to "stats"
• file_suffix: str - data file suffix e.g. if filename is stats.0.json, then suffix should be set to "json"
• compressed: bool - when True, brotli must be imported and then output data will be compressed
• schema_type: str - should be "LBDatafile" or "LBStatsfile" depends on input data. Only "LBStatsfile" is supported
• check_schema: bool - when True, validates schema (more time-consuming)

vt Data Maker

The vt Data Maker generates a dataset of JSON files that may be used throughout the DARMA-tasking organization. The generated files are compatible with LBAF, vt-tv, and vt.

If the lbaf package is installed, run with:

lbaf-vt-data-files-maker <args>

Otherwise, run:

python src/lbaf/Utils/lbsJSONDataFilesMaker.py <args>

The program can be run interactively with the --interactive argument.

Otherwise, it accepts a pre-written specification file (--spec-file) and the file stem for the resulting data files (--data-stem).

Further documentation, including usage and examples, can be found within the script itself.

LBAF in Literature

Optimizing Distributed Load Balancing for Workloads with Time-Varying Imbalance

"This paper explores dynamic load balancing algorithms used by asynchronous many-task (AMT), or ‘task-based’, programming models to optimize task placement for scientific applications with dynamic workload imbalances."