Eric,

I would think a little more about the usable capacity of your 3575.

first, figure out the space left on  filling volumes plus empty volumes
plus pending volumes.

2nd, figure the reclaimable space on full volumes
at the %reclaim level you want to run with.

Add these 2 numbers together.

For planning purposes, estimate how hard you want to drive reclaim to
maintain enough usable volumes to grow upto say
85% of the nominal capacity.  When you have to reclaim at a faster rate
then it is time to increase capacity.


--
--------------------------
--------------------------
Bill Colwell
Bill Colwell
C. S. Draper Lab
Cambridge, Ma.
bcolwell AT draper DOT com
--------------------------
In <59C645F3B051D311A4680000832FE2D401AF14A8@X0F0000>, on 02/17/00
In <59C645F3B051D311A4680000832FE2D401AF14A8@X0F0000>, on 02/17/00
   at 04:30 PM, "Loon, E.J. van - SPLXM" <Eric-van.Loon AT KLM DOT NL> said:

>Hi Bill!
>I didn't know that! I thought that ADSM would stop backups when you run
>out of scratches.
>Well, this sure changes things... I was always thinking that counting the
>amount of available scratches was a good way of predicting your ADSM
>library capacity.
>I have to look for another way of calculating ADSM's storage capacity. I
>am using a 3575 with (at this moment) 18 scratches left. So, I thought I
>had 18/320*100=5.6% left. However, I now know that ADSM starts using
>partially filled tapes from other nodes when there are no scratches left.
>I directed the output from the command q volume stgpool=tapepool to a
>text file and I imported that file into Excel. I calculated the average
>tape usage for this storage pool and the answer was 43.3%. So, instead of
>having 5% left I have 43 % left! Right?
>Wow! Guess my boss will be happy to hear this!
>Kindest regards,
>Eric van Loon