Quick Reference: mprocs Support in Breeze

Basic Command

Start airflow uses mprocs by default:

bash

breeze start-airflow

You can switch to using tmux instead by specifying the option:

bash

breeze start-airflow --terminal-multiplexer tmux

Once you select the terminal multiplexer, Breeze will remember your choice for future runs.

You can also switch terminal multiplexers by running breeze setup config:

bash

breeze setup config --terminal-multiplexer mprocs
breeze setup config --terminal-multiplexer tmux

When Breeze will start Airflow components using mprocs to manage multiple processes in a single terminal window. It will generate dynamically the required configuration based on the selected executor and options and use it, the generated configuration file is stored in a files folder inside the container, so that you can also use it outside of Breeze if needed.

Common Usage Patterns

Command	Description
`breeze start-airflow --terminal-multiplexer mprocs`	Start Airflow with mprocs (and remember the choice)
`breeze start-airflow --terminal-multiplexer tmux`	Start Airflow with tmux (and remember the choice)
`breeze start-airflow --debug scheduler`	Debug scheduler with last selected multiplexer
`breeze start-airflow --dev-mode --terminal-multiplexer mprocs`	Use mprocs in dev mode (and remember the choice)

mprocs Keyboard Shortcuts

Key	Action
`↑↓`	Navigate between processes
`r`	Restart selected process
`x`	Stop selected process
`s`	Start selected process
`a`	Add new process
`q`	Quit mprocs
`?`	Show help

Components Managed

scheduler - Airflow scheduler
api_server (3.x+) / webserver (2.x) - Web interface
triggerer - Handles deferred tasks
dag_processor - Standalone DAG processor (when enabled)
celery_worker - Celery worker (with CeleryExecutor)
flower - Celery monitoring (when enabled)
edge_worker - Edge worker (with EdgeExecutor)

Environment Variables

Variable	Purpose
`TERMNAL_MULTIPLEXER`	Use mprocs when set to "mprocs"
`INTEGRATION_CELERY`	Enable Celery components
`CELERY_FLOWER`	Enable Flower UI
`STANDALONE_DAG_PROCESSOR`	Enable standalone DAG processor
`BREEZE_DEBUG_*`	Enable component debugging
`DEV_MODE`	Enable development mode

Debug Ports (when debugging enabled)

Component	Port
Scheduler	50231
Dag Processor	50232
Triggerer	50233
API Server	50234
Celery Worker	50235
Edge Worker	50236
Web Server	50237

Installation

mprocs is pre-installed in the Breeze CI image as of Airflow 3.x development. No additional setup is required.

For older images or custom setups, you can install mprocs manually:

bash

# Download and install mprocs
MPROCS_VERSION="0.7.3"
SYSTEM=$(uname -s | tr '[:upper:]' '[:lower:]')
PLATFORM=$([ "$(uname -m)" = "aarch64" ] && echo "arm64" || echo "amd64")
curl -L "https://github.com/pvolok/mprocs/releases/download/v${MPROCS_VERSION}/mprocs-${MPROCS_VERSION}-${SYSTEM}-${PLATFORM}.tar.gz" \
  | tar -xz -C /usr/local/bin/ mprocs
chmod +x /usr/local/bin/mprocs

Mac OS X and iTerm2

Mouse clicks are not captured correctly by default in iTerm2 (which is often used by developers on MacOS). You need to configure "Enable Mouse reporting" to take advantage of the copying feature and mouse handling:

Standalone execution

You can run mprocs outside of Breeze for custom setups. Create a mprocs.yaml configuration file defining your processes, then start mprocs:

bash

mprocs -f mprocs.yaml

An example mprocs.yaml file for Airflow components can be found in this directory - it has default configurations for all major Airflow components, but you can customize it as needed by copying it elsewhere and modifying the process definitions, uncommenting the commented or adding new processes.