Determining what is causing load when server is idle.

[George Magklaras]

Seeing init in S mode in 'top' like that:
   1 root      16   0  1972  556  480 S  0.0  0.0   0:00.53 init

is not so extraordinary if you just invoke 'top'. If it is in R or other 
process mode continuously, that would be alarming.


> Another symptom that comes along with this weird non-0.00 load issue is that
> user I/O seems to "glitch" every now and then.  Almost like the hard drives
> are spinning up after being put to sleep... however, APM is disabled in my
> kernel since I am running in SMP mode.

I think that #might# be the key symptom. How exactly do you mean the 
'glitch'. Does I/O pause for an interval to the point where you notice 
it for several seconds and then continues, abort completely (I/O 
errors)? It could be that there is somekind of background reconstruction 
  or syncing happenning due to driver or hardware issues.

dmesg | grep -i md

should give you any hickups related to the RAID config. Doing also a 
'vmstat 3'

whilst you see the 'glitchy' I/O you mention might be useful. Look for a 
high number of interrupts or elevated r and b columns.

/proc/interrupts, the output of 'lsmod' and your SoftRAID configs files 
would help, as well as your kernel version.


GM