In 'idle' state, I could see that our SunFire/Solaris server consumes
2% of CPU most of the times. Before checking further about it in the
Application code, I would like to know whether the OS/Firmware does
something continuously in the background.

Can somebody clarify?

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On 19 avr, 13:03, qazmlp1...@rediffmail.com wrote:
> In 'idle' state, I could see that our SunFire/Solaris server consumes
> 2% of CPU most of the times. Before checking further about it in the
> Application code, I would like to know whether the OS/Firmware does
> something continuously in the background.
>
> Can somebody clarify?

you could try a
top -s

the -s show the system tasks, there are a few to run.
Zoot

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On Apr 19, 5:09 pm, zoot <a...@swing.be> wrote:
> On 19 avr, 13:03, qazmlp1...@rediffmail.com wrote:
> 
> 
>
> you could try a
> top -s
>
> the -s show the system tasks, there are a few to run.
> Zoot

top -S works. But, it displayes both the system and the user
processes.

How do I make it such that it displays only the system processes?

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On 19 avr, 15:18, qazmlp1...@rediffmail.com wrote:
> On Apr 19, 5:09 pm, zoot <a...@swing.be> wrote:
> 
> 
> 
> 
> 
>
> top -S works. But, it displayes both the system and the user
> processes.
>
> How do I make it such that it displays only the system processes?

top show the most demanding process on the system, I don't think there
is a way to only show system process and it's not the purpose of top.
Zoot

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On Apr 19, 2:18 pm, qazmlp1...@rediffmail.com wrote:
> On Apr 19, 5:09 pm, zoot <a...@swing.be> wrote:

> top -S works. But, it displayes both the system and the user
> processes.
>
> How do I make it such that it displays only the system processes?

prstat -a -s cpu is a reasonably good way of finding the top CPU-time
consumers, with a summary by UID.  You can further filter by UID:
prstat -a -s cpu -u root,daemon,lp say.

A system process is no different than a user process other than it is
typically running as a UID thought of as a system user.

--tim

--tim

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qazmlp1209@rediffmail.com wrote:
> In 'idle' state, I could see that our SunFire/Solaris server consumes
> 2% of CPU most of the times. Before checking further about it in the
> Application code, I would like to know whether the OS/Firmware does
> something continuously in the background.

I believe the Solaris kernel does "memory scrubbing" in the background
on machines that have ECC memory.

The idea is that you cannot detect a flipped bit (due to radiation,
hardware issues, whatever) in RAM until you access that location.
Once a flipped bit has occurred, you lose redundancy.  Should
another bit flip, you would then lose the ability to correct the
error.

The more frequently a memory location is accessed, the lower the
probability that this compounding of one error upon another will
happen.  So the idea behind memory scrubbing is to ensure that
every memory location is accessed every now and then.

I'm not positive that this is the issue (and it seems like 2% of
the CPU is too much), but it is one thing that Solaris does
continuously in the background.  Here's a useful link on the
subject:

http://www.webservertalk.com/archiv...p/t-964093.html

(That's a thread from comp.unix.solaris, a thread which I just
realized I had participated in.  Maybe that's where I originally
heard of memory scrubbing.  :-)

- Logan

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