This event is used to wait for disk file operations (for example, open, close, seek, and resize). It is also used for miscellaneous I/O operations such as block dumps and password file accesses. Wait Time: The wait time is the actual time it takes to do the I/O Parameter Description FileOperation Type of file operation…
This event is used to wait for the writing of the file headers. Wait Time: The wait time is the actual time it takes to do the I/O Parameter Description file# See “file#” block# See “block#” blocks This is the number of blocks that the session is trying to write in file# starting at block#
This event occurs in the DBWR. It indicates the time that DBWR spends waiting for I/O completion. If asynchronous I/O is available, then the db file asynch I/O submit wait event captures any time spent in submitting I/Os to the underlying storage. When asynchronous I/O is not available, db file parallel write captures the time…
This happens during recovery. It can also happen during buffer prefetching, as an optimization (rather than performing multiple single-block reads). Database blocks that must be changed as part of recovery are read in parallel from the database. Wait Time: Wait until all of the I/Os are completed Parameter Description files This indicates the number of files…
When asynchronous I/O is available, this wait event captures any time spent in submitting I/Os to the underlying storage.
Oracle Database Internal Mechanism 