Size for FileCache HP UX 11.31 ia Database Server

[JC Arzate]

Size for FileCache....

As many other people (I mean DBA´s) I´m triying to tune Memory in Batabase Server, actually we got a Total RAM for 32 GB but half of this (I mean 16 GB) was set for FileCache so My question is should I or not to set this Cache memory lower and take it for my Database Instance?? Reason Behind is a permanent use (100%) of RAM all time.

Im triying to confirm is there´s a risk in set this Kernel parametert at low level, I mean HP see some risk?? Do we can just set it down??
Of course according original Note I´ll use this resources for Database Instance.
$ uname -a
HP-UX ebsbdpro B.11.31 U ia64 1659469384 unlimited-user license
$ kcusage -ht filecache_max
Tunable: filecache_max
Setting: 16307607550
Time Usage %
=============================================
Thu 09/16/10 11:15 CDT 15955652608 97.8
Thu 09/16/10 11:20 CDT 15954894848 97.8
Thu 09/16/10 11:25 CDT 15962861568 97.9
Thu 09/16/10 11:30 CDT 15928664064 97.7
Thu 09/16/10 11:35 CDT 15933124608 97.7
Thu 09/16/10 11:40 CDT 15883358208 97.4
Thu 09/16/10 11:45 CDT 15909007360 97.6
Thu 09/16/10 11:50 CDT 15794868224 96.9
Thu 09/16/10 11:55 CDT 15821049856 97.0
Thu 09/16/10 12:00 CDT 15717101568 96.4
Thu 09/16/10 12:05 CDT 15682842624 96.2
Thu 09/16/10 12:10 CDT - -
$

Expect for comments.

[likid0]

Yes, you can lower your filecache size, and give it to the SGA, oracle will make better use of it.


you can use the sar -b to check on the cache hits percentage.

[JC Arzate]

Ok Daniel, I´ll request for change it and test (I mean will assign more memory to SGA and see performance)

Thanks for Support.

Regards.

JC

[nightwich]

Hi Arzat


I think you should have no problem to reduce this value.


In my SAP system I have this value like this.

filecache_max=5%
filecache_min=3%


Regards.

[JC Arzate]

Thanks nigthwitch,

As said I´ll apply it and we´ll update with results.

Kind regards.

JC

[nightwich]

Hi Arzat


Try to allways give some points to usefull answers.



Regards.

[SoorajCleris]

Hi,

Just see the recent thread..

http://forums11.itrc.hp.com/service/forums/questionanswer.do?threadId=1446651

Regards,
Sooraj

[Rita C Workman]

Reduce filecache max/min as stated above.

Reduce ninode value to something more reasonable. Run sar -v to get a better idea of what the number should be.

Reduce vx_ninode - for 32Gb of RAM you might set it to something around 150-200,000. Yes that's 200000. Otherwise the system will allocate space based on RAM and what it will setup is far more than these figures.

Just a couple suggestions,
Rita

[JC Arzate]

Thanks for comments everybody.

Kind Regards. JC

[nightwich]

Hi JC

You should allways assign the points to the answers.


Regards.