kernel parms for new L1000 box

[Kevin Bingham]

Hi all,
I have searched the forums briefly for the answers to the following query, but most of the hits I have found are quite specific with respect to the configuration variables, so I am posting with my specific configuration in the hopes that I get responses that are valid to my scenario...

Here it is. We have just taken delivery of a new L1000/9000/800 box that has 1.5Gb RAM, 2x18Gb SCSI disks running 11.11 software. The machine was supplied with 512Mb RAM, and I have added a further 1Gb RAM since delivery so kernel doesn't know about this...

The box is to be used for porting work only, and as such has a small Oracle 9i database, and some 3rd party software which operates in a 2-tier client/server architecture, with the clients on a windows box and the servers on L1000, which then use the Oracle db...

Now for the question... as this is basically a factory installation of the 11.11 OS, I was wondering which if any of the kernel parms should be tuned for the picture I have painted, especially with respect to the new memory that I have added.

I have attached a txt file that contains output from kmtune ans sysdef...

Thanks in advance for 10-pointer replies...

Regards
Kevin

[Ravi_8]

Hi Kevin

If the system boot well after upgrading RAM/CPU... then the upgrade is succeeded. Now u can see memory in your m/c( using sam/dmesg). you no need to change any kernel parameters if RAM or CPU upgraded.

but to install oracle 9i, you need to change the kernel parameters

look at the link.

http://docs.oracle.com/HTML_Storage/a90357/toc/htm

[Kevin Bingham]

The machine boots fine... the RAM upgrade is not the issue...

Also, you link seems to be broken, I get a 404 page not found error when I click on it.

Thanks anyway

Kevin

[Ravi_8]

Hi,

it's

http://docs.oracle.com/HTML_Storage/a90357/toc.htm

[Trond Haugen]

I think what ravi was saying was that the kernel do know about youe memory. Which brings me to my point about DBC. With a dbc_*_pct range 5-50 you will potensially give the system an awfull lot of bugger cache to manage. With a db-system it's often advisable to have a static dbc size and as a roule you should not have more than 500Mb. You could set you dbc_max_pct to 30 and monitor the usage before you decide on a fixed value.

Regards,
Trond

[Pete Randall · Accepted solution]

Kevin,

The default kernel parameters supplied are fine if you're not going to do any serious application work. However, if you are going to be running applications, in your case Oracle, then the application venor will have their own requirements for kernel tuning. Consult the link Ravi gave you for Oracle's requirements.

Other than Oracle requirements, you definitely need to look at dbc_max_pct, as pointed out by Trond (though I would go lower - more like 10%), and should probably look at raising maxusers (and the parameters related to it by formula) to a realistic value for our situation.

That's pretty much the nutshell version.

Pete