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Oracle: Init parameter FILESYSTEMIO_OPTIONS

filesystem_options controls whether Oracle files are accessed with asynchronous I/O and/or direct I/O.

The value of filesystem_options can be set to

`none`	Synchronous and buffered I/O
`setall`	Asynchronous and direct I/O
`directIO`	Synchronous and direct I/O
`async`	Asynchronous and buffered I/O

Obviously, asynchronous I/O and/or direct I/O will only be used if it's available (regardless of the setting of this init parameter).

Asynchronous I/O can also be disabled by setting disk_async_io) to false.

Because ASM bypasses the filesystem layer, filesystem_options has no effect when ASM is used.

See also