Data buffering and the Audit Database

If the PI Snapshot Subsystem is not running, data from non-buffered API and PINet nodes can be lost. However, because it plays a key role in preventing data loss, the PI Snapshot Subsystem buffers all events until they can be successfully written to the PI Archive Subsystem.

Likewise, when the Audit Database file for the PI Snapshot Subsystem is closed, the subsystem continues to accept new audit record values in an internal buffer. These records are cached until the file is re-opened and the cached records are transferred to the Audit Database.