Oracle 11.2 new v$ iostat views

Oracle release 11.2 has introduced new iostat views that show the resource usage against the physical disk spindles.

These are very important new AWR tables because it allows Oracle to look outside of the database and get statistics directly on disk service rimes.

v$iostat_consumer_group

v$iostat_file:  This has valuable file I/O statistics.  What is missing is the all-important disk enqueues which would indicate disk contention for a device.  However, this could be inferred from read service time, provided that the two AWR snapshots are less then 60 seconds apart and the file is not striped across multiple disks:

file_no	File identification number
filetype_id	Type of file (for example, log file, data file, and so on)
filetype_name	Name of the file, in the case of a data file or temp file. For all other files, a corresponding string to be displayed (for example, ARCHIVELOG).
small_read_megabytes	Number of single block megabytes read
small_write_megabytes	Number of single block megabytes written
large_read_megabytes	Number of multiblock megabytes read
large_write_megabytes	Number of multiblock megabytes written
small_read_reqs	Number of single block read requests
small_write_reqs	Number of single block write requests
small_sync_read_reqs	Number of synchronous single block read requests
large_read_reqs	Number of multiblock read requests
large_write_reqs	Number of multiblock write requests
small_read_servicetime	Total service time (in milliseconds) for single block read requests
small_write_servicetime	Total service time (in milliseconds) for single block write requests
small_sync_read_latency	Latency for single block synchronous reads (in milliseconds)
large_read_servicetime	Total service time (in milliseconds) for multiblock read requests
large_write_servicetime	Total service time (in milliseconds) for multiblock write requests
asynch_io	Indicates whether asynchronous I/O is available for the file (ASYNC_ON) or not (ASYNC_OFF)
retries_on_error	Number of read retries on error