Environment variables:

• ARK_ROOT: The installation directory of ARK. Defaults to /usr/local/ark when unset.

export ARK_ROOT=/usr/local/ark  

• ARK_SCHEDULER: The scheduler used by ARK. The available schedulers are Default and Simple. Defaults to Default when unset. Simple is a simple scheduler that is used for debugging.

export ARK_SCHEDULER=Default  

• ARK_LOG_LEVEL: The log level of ARK. The available log levels are DEBUG, INFO, WARN, and ERROR. Defaults to INFO when unset.

export ARK_LOG_LEVEL=DEBUG

• ARK_IPC_LISTEN_PORT_BASE: The base port number for IPC communication. Defaults to 42000 when unset. If we start multiple ARK processes on the same machine, different processes should use different port numbers. For example, if the base port is set to 42000, the first process will use 42000, the second process will use 42001. Note that if the port number is already in use, ARK will fail to start.

export ARK_IPC_LISTEN_PORT_BASE=42000