On Mon, 20 Dec 2004 15:10:09 +0100, Andrea Gangini <a.gangini@xxxxxxxxxx> wrote:
> Hi, I noticed this behavior on one of my server (mail server, postfix +
> amavisd + spamassassin, 2,8ghz Xeon, kernel 2.6.9-1.681_FC3smp).
>
> Here's the output of top command:
>
> top - 15:04:35 up 4 days, 6:33, 2 users, load average: 15.00, 15.03,
> 15.05
> Tasks: 160 total, 1 running, 159 sleeping, 0 stopped, 0 zombie
> Cpu(s): 0.2% us, 0.2% sy, 0.0% ni, 99.7% id, 0.0% wa, 0.0% hi, 0.0% si
> Mem: 505484k total, 405564k used, 99920k free, 10836k buffers
> Swap: 1052152k total, 33032k used, 1019120k free, 62548k cached
>
> Here's vmstat 3:
>
> The machine is apparently under NO load, NO cpu used, all services run
> at great speed (postfix, samba, webmin) and no apparent problems.
>
> Any clues/suggestions?
first of all, the definition of 'load average' is 'number of processes
waiting for something'. that can include processes that are hung on a
particular I/O request.
However, 15 of them with no actual cpu used and no other system
problems (failing hardware is a common source of problems) does seem
quite unusual.
Probably best to ps auxwww, and check out column 8. it will tell you
what state the process is in. as per the man page, you're probably
interested in Z and D processes:
PROCESS STATE CODES
D uninterruptible sleep (usually IO)
R runnable (on run queue)
S sleeping
T traced or stopped
Z a defunct ("zombie") process
For BSD formats and when the "stat" keyword is used, additional letters
may be displayed:
W has no resident pages
< high-priority process
N low-priority task
L has pages locked into memory (for real-time and custom IO)
- Kevin
