Buffered I/O (-r)

Operating system and syntax UNIX / Windows 
-r
Use with Maximum value Minimum value Single-user default Multi-user default
CC – – Unbuffered I/O Unbuffered I/O

Use Buffered I/O (-r) to enable buffered I/O to the before-image file. In most cases, avoid using this parameter because it might put database integrity at risk.

CAUTION: A database running with the -r parameter cannot be recovered after a system failure. If the system fails, you must restore the database from a backup and restart processing from the beginning.