Re: kproc

"Nicholas Buckley" <nbuck_at_globalnet.co.uk> writes:

> Hi everyone,
>

[snip]

> Question 1)
> Why are there so many kprocs?

Because there are :) AIX puts lots of system services into "kernel processes", AKA kprocs.

>
> Question 2)
> Is this normal ?

Yes.

>
> Question 3)
> What does this tell me about the way the system is performing?

Depends. If a kproc other than 516 and its buddies (see next question) is using lots of CPU, then you might have a performance tuning issue to address. Unfortunately, since 'ps' doesn't tell you which kproc is which, you may never know what the issue is. Get a copy of the free 'monitor' utility for AIX, which tries to give each kernel process a semi-informative name.

>
> Question 4)
> The first four entries under ps aux are using up over 80% of CPU time. Can I
> do anything about this ( especially as the other 10 are using almost no CPU
> at all )
>

The first four are the infamous 'wait' processes. Each CPU on an AIX system has an associated wait process. On a 4-CPU machine, therefore, there are four of them. They occupy process slots 2, 3, 4, and 5 (slot 1 belonging to init and slot 0 to swapper). Their process IDs under AIX 4 are always 516, 774, 1032, and 1290 (on a 4-way machine). They have the lowest dispatching priority of any process on the system, and are merely used for accounting purposes to accumulate all unused CPU slices. Thus, if your wait processes are using up over 80% of CPU time, your CPU is over 80% idle. If you want to do anything about this, run more CPU-intensive processes :)

-- 
Greg Wimpey
greg.wimpey_at_waii*removetomail*.com.invalid