The data provided is also a average value since boot time. Run the -x as suggested below but run it via a interval of around 5 seconds. You very well could be having i/o issue, it is hard to tell from the overall average value you provided. Collect "iostat -x 5" during the times when you see slow reads and see how busy the disks are.


On Thu, Feb 3, 2011 at 3:21 AM, Peter Schuller <> wrote:
> $ iostat

As rcoli already mentioned you don't seen to have an I/O problem, but
as a point of general recommendation: When determining whether you are
blocking on disk I/O, pretty much *always* use "iostat -x" rather than
the much less useful default mode of iostat. The %util and queue
wait/average time columns are massively useful/important; without them
one is much more blind as to whether or not storage devices are
actually saturated.

/ Peter Schuller