tunnable kernal parameter

[navin]

Hello,
I need to bring down the dbc_max_pctr to 25 from 50
Can i do it in running system...as below

kctune dbc_max_pct = 25

i do want the system to be restarted
Thanks in advance

[James R. Ferguson]

Hi Navin:

Yes, the 'dbc_max_pct' is dynamically tunable on 11.23 and later. Your syntax is correct.

Regards!

...JRF...

[David Bellamy]

navin: since you did not tell us what OS you are using I'm going to assume that it is HPUX 11.23 and yes you can use kctune to change that parameter on a running system without a reboot.

[Asif Sharif]

This can be easily done through SAM also.

SAM->Kernel Configuration->Configurable Parameters->
Select the parameter and double click. Change value to desired value e.g.(25).

or

do it with command.

#kctune dbc_max_pct = 25

it will show you the output like this.

* The automatic 'backup' configuration has been updated.
* The requested changes have been applied to the currently running system.
Tunable Value Expression Changes


Regards,
Asif Sharif

[Rasheed Tamton]

Hi Navin,

If your OS is 11.23 you can change it online (without a reboot)

kctune -v dbc_max_pct
(Check the last line of the result, can change immediately means dynamic)

or
if you want to be more satisfied, then use
kcweb -t
enter Tunables
scroll down until you see the dbc_max_pct. Check the Tuning Capability column to know whether it is static or Dynamic. If you press "d" it will show all the dynamic tunables.

Regards,
Rasheed Tamton.

[Jeeshan]

depends upon your OS version.

in 11iv1, you need restart but from 11.23, its dynamic. no need restart.