On Fri, 26 Mar 2004 10:23:27 +0000
"Frost, Dave" <Dave.Frost AT SUNGARD DOT COM> wrote:

> Hello all,
>
> Does anybody have any experience with TSM performance of STK 9940's ?

We do ;-)

> We are running 9840's with colocation and have found the performance
> for large restores of a small file nature to be very good.
> The only problem with 9840 is the 20GB limitation. I know that large

upgrade to 9840C, you'll get 40 GB on the same tapes.

> servers will span multiple tapes and the multi-thread restore works
> exceptionally well with this. The only problem is that with growing
> data quantities, an L700 fills up very quickly.
>
> Using 9940's would triple the capacity of an L700. But we need to
> ensure we would maintain the performance that we are seeing on the
> 9840's. I understand that a 9940 is going to be a physically longer
> tape and as such certain stats are not comparable to the 9840. But
> does the repositioning and backhitching that is so evident with a
> large TSM restore compare to that of a 9840.
>

We currently only user the 9940B drives for our copy storagepool. So I
can't really tell about restores of a large number of small files. I'd
expect the 9840 to perform better in that departmant, but by how
much????

Maybe you could replace some of your 9840 by 9840C drives and some with
9940B, just like we have....

> -=Leigh=-


--
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Remco Post

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