Again this being done for performance, it is sometimes hard for a DBA to know when he might need an AIO VP and where to look to get this information.
AIO VP’s are used on operating systems that do not support KAIO, the database server uses the AIO class of virtual processors to perform database I/O that is not related to physical or logical logging.
The database server uses the CPU class to perform KAIO for database I/O when KAIO is available on a platform.
If the database server implements KAIO, a KAIO thread performs all I/O to raw disk space, including I/O to the physical and logical logs.