Databases Reference
In-Depth Information
RAID level 0+1
RAID level 0+1 is also known as RAID level 10; it's the result of RAID level 0 and RAID level 1
arrays being used together. So, we have a striping and mirroring solution that allows excellent
performance in read operations and very good performance in write operations, due to the
additional write operation required by mirroring. RAID level 0+1 ensures optimal protection
against failures, thanks to mirroring.
The only defect of RAID level 0+1 subsystems is the cost of this solution, but it can be used to
store every type of Oracle database file with optimal performance.
See also
F
The
Tuning memory to avoid Operating System paging
recipe in
Chapter 9
,
Tuning Memory
Using asynchronous I/O
In this recipe we will see how to use asynchronous I/O to obtain better performance from our
I/O subsystem.
How to do it...
The following steps will describe the use of asynchronous I/O:
1.
Connect to the database as
SYSDBA
:
CONNECT / AS SYSDBA
2.
Verify whether asynchronous I/O is enabled:
SHOW PARAMETER FILESYSTEMIO_OPTIONS
3.
Enable asynchronous I/O, if it is not enabled:
ALTER SYSTEM SET FILESYSTEMIO_OPTIONS=SETALL SCOPE=SPFILE;
4.
Shut down the database instance:
SHUTDOWN IMMEDIATE
5.
Start and open the database:
STARTUP OPEN
6. Verify the change in system configuration:
SHOW PARAMETER FILESYSTEMIO_OPTIONS
