Allen,

If this is tape-to-tape, perhaps the input tape is repositioning (spacing,
or seeking).  This can happen for reclaims, for example, as you are
skipping over expired files.  Just a thought.

..Paul


At 04:50 PM 11/10/2008, Allen S. Rout wrote:

>> On Mon, 10 Nov 2008 13:22:32 -0800, "Clark, Robert A"
<Robert.Clark AT providence DOT org> said:

> What is the source and destination for the data? Is it coming from
> disk or tape? Is it going to disk or tape?

All, or vast majority, tape-to-tape.

> Idle percentage doesn't tell much, especially if the systems are doing a
> lot of I/O wait.

Very little IO wait.  Not all the time, of course.  But the slow
traffic persists across multiple minute periods of maybe 5% IOwait.




- Allen S. Rout

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