BPEL process types

BPEL processes can be either long-running or microflows.

Long-running processes

A long-running BPEL process is interruptible, and each step of the process can run in its own physical transaction. Long-running BPEL processes can wait for external stimuli. Examples of external stimuli are events that are sent by another business process in a business-to-business interaction, responses to asynchronous invocations, or the completion of a human task.

A long-running process has the following characteristics:

Runs in multiple transactions.
Interacts with services synchronously and asynchronously.
Its state is stored in the runtime database, which makes the process forward-recoverable.

Microflows

A microflow runs in one physical thread from start to finish without interruption. Microflows are sometimes referred to as non-interruptible BPEL processes. Microflows can have different transactional capabilities. A microflow participates in the unit of work that can be either a global transaction or an activity session.

A microflow has the following characteristics:

Runs in one transaction or activity session.
Normally runs for a short time.
Its state is transient, and it is therefore not stored in the runtime database.
It typically invokes services synchronously.
It can have only non-interruptible child processes.
It cannot contain human tasks, wait activities, non-initiating receive activities, or pick activities.