iostat during cp2 update

-bash-# iostat

avg-cpu:  %user   %nice %system %iowait  %steal   %idle
          10.82    0.02    1.25    2.32    0.00   85.60

Device:            tps   Blk_read/s   Blk_wrtn/s   Blk_read   Blk_wrtn
sda              61.68      4646.95       520.42 27225618403 3049042944
sda1              1.12         0.30        17.76    1770307  104049032
sda2             60.56      4646.64       502.63 27223786360 2944827736
sda3              0.00         0.01         0.03      61096     166176
sdb              61.65      4646.99       520.39 27225877899 3048876768
sdb1              1.12         0.30        17.76    1754913  104049032
sdb2             60.52      4646.69       502.63 27224121514 2944827736
sdb3              0.00         0.00         0.00        832          0
md2              62.39         9.88       495.50   57878898 2903053760
md1               1.85         0.59        14.61    3446994   85584400