Process Issues

[shruti_1]

Hi there is a process that we run called post_rate that pushes the data in the oracle. Since yesterday I don't know what has happened that process is taking jerks sometimes it is running at a very high rate and sometimes it runs at a very small rate.

From sar output I have found that this process takes as large as 90% of CPU utilization and as low as 0.16 of cpu utilization even if the cpus are sitting idle . Could anyone help me out on this

[Peter Godron]

Hi,
is this the same machine as in your other problem? http://forums1.itrc.hp.com/service/forums/questionanswer.do?threadId=1031131

If so, then the problem might be that the oracle process is waiting for the disk to become available (0.16%) and then goes to 90%. Please correct my assumption by supplying more details.

[Raj D.]

Shruti ,

You have to monitor the system performance over a period of time. And collect the sar output in non peak hours also using cron.
And you can come to know why this symptom is happening.

sar -u -M 5 10 > sarout_cpu.txt
And check if always one cpu is getting used for that process or any other symptom.

also check with vmstat 5 5 , glance , top.

also you must investigate with DBA , as what post_rate does actually.

Cheers,
Raj.

[shruti_1]

My issue has been resolved it was related to buffer cache.

One more question I have if there is a process that is running at say 90% cpu power is it possible to lower down its value to a larger extent say 10 % or so

[Peter Godron]

Hi,
you can alter the PRIORITY of the job with renice.
See "man renice"

[shruti_1]

I have tried renice but it dont decrease the value to the larger extent is there any other method

[Peter Godron]

Hi,
the only other method I know of is buying products such as:
Process Resource Management (PRM) or
Workload Manager

[shruti_1]

Are there any commands by which it can be done

[Peter Godron]

Hi,
I don't think there are any online commands.
Also,please read:
http://forums1.itrc.hp.com/service/forums/helptips.do?#28