Db_block_size Requirements For Direct IO / Concurrent IO

(Doc ID 418714.1)

Last updated on DECEMBER 06, 2016

Applies to:

Oracle Database - Enterprise Edition - Version to [Release 9.2 to 12.1]
IBM AIX on POWER Systems (64-bit)
***Checked for relevance on 08-Jul-2016***


Running benchmarks with Direct IO and Concurrent IO.

disk_asynch_io is set to true, filesystemio_options = setall and db_block_size=8k

Will DIO and CIO be used when the operating system uses 4k blocks and Oracle is set to 8k blocks or is it required to set the db_block_size to 4k so it matches exactly what the OS has?


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