SCHED_NOAGE and Oracle

[Miguel Angel Aliaga]

Hi,
I`m working with an OLTP environment (Oracle 9i and HP-UX 11i). I still havent´t activate the Oracle recomendation about the SCHED_NOAGE schedulling policy.

Are there any experience about Sched_noage+Oracle out there ?

Regards

[Steven E. Protter]

After years of working witht he environment you are asking on I can say this:

We have never had to change the default scheduler.

Now At my last shop the DBA did do the following:

Installed and ran the stats pack so the database could learn what the activity was like and optimize itself.

Ran reports regularly to look at trends and patterns to see if the performance could be improved.

I took note of that during the only real disaster I've been through in my career. While restoring the database the first few hours of activity went very slowly until we restored stats data and tablesspace and the database could take into account prior usage.

SEP

[Yogeeraj_1]

hi,

also have a look at metalink note: 239127.996

regards
yogeeraj

[Indira Aramandla]

Hi Miguel Angel,

This feature is available from Oracle8i 8.1.7.2 onwards.

This could be suited to online transaction processing (OLTP) environments because OLTP environments can cause competition for critical resources. Overall performance improvements of 5 to 10% for OLTP applications

The parameter is of interger type with default value=0 and it can be set dynamically using Alter Session ot Alter system.
Range of values are 154 to 255 (for HP-UX 11.0) and 178 to 255 (For HP-UX 11i)

Oracle9i Real Application Clusters Multiple instances can have different values, and you can change the values as needed.
On HP-UX IA64 platform, must be running at least the 9.2.0.3 patchset level. There is a one-off patch available for 9.2.0.2 on MetaLink through Patch Number 2821953.

When setting this parameter to the highest fixed priorities
hpux_sched_noage=154 (for HP/UX 11.0)
hpux_sched_noage=178 (for HP/UX 11i)

If the parameter setting is out of range, Oracle sets the parameter to a permissible value and continues with the SCHED_NOAGE policy with the new value. It also generates a message in the alert_sid.log file about the new setting. Oracle Corporation recommends that you set the parameter to the required priority level for Oracle processes.

Indira A

[Eric Antunes]

Hi Miguel,

See also Notes 217990.1 and 218027.1 from Metalink.

PS: read also this about the forum point system: http://forums1.itrc.hp.com/service/forums/helptips.do?#28

Best Regards,

Eric Antunes