Glance + Shows that CPU utilization is 100%

[Suraj Singh_1]

Hi,
Can somebody tell me as to how to tune my kernel so that i can reduce the CPU utilization?

Rgds,
Suraj

[Pete Randall]

The only way you're going to be able to reduce the cpu utilization is by reducing the load on the machine and the only way to do that with kernel tuning is to reduce something like maxusers or nprocs to limit the number of users or processes that are allowed on the system simultaneously. I'm afraid that is not going to make your users very happy.

The only way to really address this is to very carefully review what is actually running on the machine to see if there are unnecessary processes that could either not be run at all, or postponed to a less busy time. Failing any progress in this direction, you will need to look at upgrading either the number of or speed of your cpu(s).


Pete

[Peter Godron]

Suraj,
have a search of the forums with :
"Glance 100% CPU"
returns quite a few possible starting points.
Regards

[RAC_1]

Do you have glance installed?? If yes, start glance and look at the process that are using CPU maximum.

[Peter Godron]

Suraj,
please double check your 100% from glance by running top.

Glance had/has(?) a problem whereby it adds up all the processors into one.

[Gordon Morrison_1]

Hi Suraj,
2 things:
First, just because CPU utilisation shows as 100% doesn't necessarily mean you have a problem. If CPUs go up to 100% for a while, then come back down, and only go back up occasionally, it may just mean that your system is working hard, but coping with the load. Even if it stays at 100% for most of the time, it still may not be a problem. The question is, how responsive is the machine while it's at 100%? It's only a problem if there are signs/symptoms that it can't cope with what it's being asked to do, e.g. slow response, jobs taking too long, users complaining etc.
Second, it's not as easy as that. You need to look at WHY the CPU's are running at 100%. Maybe there's a runaway process that's using it all, maybe there is just too much for it to do, and it can't cope with the workload. It's quite possible that tuning the kernel would improve performance, but we really need more information.

[Suraj Singh_1]

HI All,

Thanks for all your suggestions.
The system response remains good even during 100% CPU utilization. Oracle applications consumes most of the CPU.
Utilization remains 100 % for about an hour or so during the day. Guess that's not a problem.

Rgds,
Suraj