Re: funny idle time from time

[Brian May <bam@debian.org>]

>>>>> "Matt" == Matt Zimmerman <mdz@debian.org> writes:

    Matt> On Fri, Aug 31, 2001 at 02:37:17PM +1000, Brian May wrote:
    >> Top says on an completely idle system (well.. should be almost
    >> completely idle): [...]  CPU states: 0.2% user, 57.4% system,
    >> 0.8% nice, 41.6% idle [...]  PID USER PRI NI SIZE RSS SHARE
    >> STAT %CPU %MEM TIME COMMAND 3 root 19 0 0 0 0 SW 56.9 0.0 4:39
    >> kapm-idled [...]  I could make a few guesses at what is going
    >> on here (probably related to the kapm-idled task, too), but
    >> first question: How does top calculate the idle time?

    Matt> Idle time is time in which the CPU is not executing any
    Matt> instructions.  kapm-idled executes HLT instructions to save
    Matt> power, so this time is not strictly idle, though it is time
    Matt> in which no user process or other kernel process is
    Matt> executing.

Then why is it included under system time? I thought it would be user
time.

Also, if a computer is running slowly, but top says the CPU has plenty
of idle time and free RAM, is there anyway I can find out what is
wrong?

I noticed a Pentium system just before, which seemed too slow to a
crawl while doing anacron stuff on startup. However, top reported the
mandb command was only using 10% CPU time.

So while I would expect some slow down, this seemed excessive (X
windows took ages to update, etc). Mozilla and X were the only other
programs "running" (if you discount the idle system daemons).

I have /home NFS mounted, but would assume that this couldn't be a
problem...?

Other potential thing, is that there is something funny with this
computer, perhaps a hardware problem, but that doesn't seem to make a
lot on sense (to me) either.

The only potentially strange thing I can see is this zombie process:

root       117  0.0  0.0  1464    4 ?        S    11:03   0:00 pump -i eth0
root       118  0.0  0.0     0    0 ?        Z    11:03   0:00  \_ [eth0 <defunct>]
root       120  0.0  0.0     0    0 ?        SW   11:03   0:00  \_ [eth0]

which seems to be a "standard" feature, but only on this
computer. These processes come back after a reboot.

Another computer only shows the top process, and none of these silly
"eth0" processes.
-- 
Brian May <bam@debian.org>