Strang iostat numbers

[Gordon Messmer]

Carlos H. Reimer wrote:
>  
> The server is showing up normally 100.00% disk utilization but this 
> morning I´ve shutted down the database and the iostat was still showing 
> 100.00 %util.
...
> Device:    rrqm/s wrqm/s   r/s   w/s  rsec/s  wsec/s    rkB/s    wkB/s 
> avgrq-sz avgqu-sz   await  svctm  %util
> sda          0.00   0.00  0.00  0.00    0.00    0.00     0.00     
> 0.00     0.00 451876.46    0.00   0.00 100.00
> sdb          0.00   0.00  0.00  0.00    0.00    0.00     0.00     
> 0.00     0.00 451876.46    0.00   0.00 100.00
> md1          0.00   0.00  0.00  0.00    0.00    0.00     0.00     
> 0.00     0.00     0.00    0.00   0.00   0.00
> md0          0.00   0.00  0.00  0.00    0.00    0.00     0.00     
> 0.00     0.00     0.00    0.00   0.00   0.00

Check /proc/mdstat.  Is one of your RAID devices rebuilding?

Also try watching iostat for more than one sample:

iostat -x 2