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Oracle Database - DISK_ASYNCH_IO parameter


For optimum performance make sure you use asynchronous I/Os. See asynchronous stream

TRUE is the default parameter value for the majority of platforms.

gerardnico@orcl>SHOW PARAMETER disk_asynch_io

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------
disk_asynch_io                       boolean     TRUE
SELECT * FROM v$parameter WHERE LOWER(name) = 'disk_asynch_io' ;

These parameters enable or disable the operating system's asynchronous I/O facility. They allow query server processes to overlap I/O requests with processing when performing table scans.

Asynchronous operations are currently supported for parallel table scans, hash joins, sorts, and serial table scans. However, this feature can require operating system specific configuration and may not be supported on all platforms.

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database/oracle/disk_asynch_io.txt · Last modified: 2015/05/04 11:17 by gerardnico