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[C. Linus Hicks]

On Sun, 2004-06-20 at 06:16, Fons van der Beek wrote:
> > On Sat, 2004-06-19 at 14:39, Fons van der Beek wrote:
> > > > On Sat, 2004-06-19 at 02:29, Fons van der Beek wrote:
> > >
> > > I'am really sorry, the overall cpu usage is 95% user and 5% system usage
> > > But all processes together dont come near the summ ................(also
> not
> > > with i pressed)
> > >
> > > I realy don't get it.... I'am converting emails, mozzilla, dbmail (mysql
> > > database) but i don't see them
> > > i has been pressed, u with blank has been pressed, sorted on cpu % but
> > > no............I don't get it
> >
> > Is it always showing 95% utilization? It has been my experience that
> > many processes on Linux systems are very short-lived; shorter than the
> > cycle time of top. This is especially true for any machine with a
> > multi-gigahertz CPU.
> 
> Pentium 4 celeron / 768 MB memory
> 
> > When I run make on a large software package, it is obvious from its
> > output that there are many invocations of the compiler, and the total
> > CPU usage is quite high, but I may not see any process in top with
> > greater than 5% CPU. They all (most all) complete between cycles of top,
> > therefore top will not see those processes. top takes a snapshot of the
> > system at the time it wakes up. Any process that exits prior to a
> > snapshot will not be reported by top.
> 
> I never expierenced that while making files I allways had (on Redhat 8.0 2.4
> kernel) a good summ of
> the cpu %  of each process
> 
> > Perhaps you need to look at the rate of process creation: gkrellm can do
> > this.
> 
> I looked at gkrellm, I guess (not complety sure if i interpret the graph ok)
> that i have 6 forks pro second.
> i still cant explain why there is such a enormous difference between
> CPU-usage overall and cpu usage
> for the main processes, i'am checking in data and mysqld has 0% CPU
> utilization.......
> 
> Do you know of any other tools which show cpu usage for each process?

ps can also show you cpu utilization, but my understanding is that its
information comes from the same place top gets it. Have you tried
turning on process accounting? That should give you more information
about completed processes. man accton.
-- 
C. Linus Hicks <lhicks at nc.rr.com>