Issues with top

[Andrew Bacchi]

Top is only reporting what it sees, it is not the cause.  I sometimes 
see behavior as you are reporting.  Often it's due to either a bad 
process, poorly written code, or a possible attack to the kernel, ddos.  
I've watched CPU0 at 100%, then it will move to CPU1 at 100%, and leave 
CPU0 at < 1%, and back again.   I used to see it happen on a test system 
after the M programmers wrote a new function that went haywire.

I've never done a search to find the cause on my Linux boxes, since it 
usually only lasts for a few minutes.  It does however wreck havoc on my 
systems.

Do a 'cat /proc/loadavg' to see the current dynamic load average. or try 
'uptime' that too reports load average.  It may be normal for an Oracle 
server to have a load this high.  Also look into 'sar' data to get a 
history of your machine.

Knabe, Troy wrote:
> I have a development box that has Oracle Application Server on it.  Yesterday we received a complaint that it was "slow" and top showed 0% idle and load averages of 15+ across all three settings.  Then after a minute or two cpu went back to 99% idle but even today the load averages show 15+, but the CPU continues to be 99% idle.  There does not appear to be i/o wait, and after the minute or two yesterday performance of the application is as expected.  Anyone else seen issues with top like this before?
>
> Thanks
> -Troy
>   

-- 
veritatas simplex oratio est
        -Seneca

Andrew Bacchi
Systems Programmer
Rensselaer Polytechnic Institute
phone: 518.276.6415  fax: 518.276.2809

http://www.rpi.edu/~bacchi/