I think I can answer this:

If a cartridge is to be reclaimed, and you have collocation turned on in the
storage pool:

If the input cartridge has only 1 client's data on it:

*       ADSM will take the data from that cartridge, and write it to a
"filling" cartridge in the storage pool (one that has free space left at the
end) which already contains data from that same client.

*       If there is not a "filling" cartridge containing data from that
client, and there are scratch tapes available to the storage pool, ADSM will
start a new cartridge for that client.

*       If there is not a "filling" cartrdige containing data from that
client, and there are NO scratch tapes available to the storage pool, ADSM
will put the data on whatever "filling" cartridge it can find (probably the
one with the most available space, but I'm not sure about that).

If the input cartridge has several clients' data on it:
ADSM will repeat the process above for EACH client on the input tape.


A side effect is that if you start out with a non-collocated storage pool
and want to turn collocation on, all you have to do is change the properties
of the storage pool.  ADSM will create any new tapes in the pool collocated,
and the pool will gradually become all collocated as reclaims occur.

Hope that answers the question...

***************************************************************
Wanda Prather
The Johns Hopkins Applied Physics Lab
443-778-8769
wanda_prather AT jhuapl DOT edu

"Intelligence has much less practical application than you'd think" -
Scott Adams/Dilbert
***************************************************************



> -----Original Message-----
> From: Sanders, David [SMTP:DSanders AT INTERNAL.MASSMUTUAL DOT COM]
> Sent: Thursday, January 14, 1999 6:26 AM
> To:   ADSM-L AT VM.MARIST DOT EDU
> Subject:      colocation and reclaimation for a local storagepool
>
> I've tried to find discussion in the archives specifically about this and
> haven't yet, so I thought I'd ask this question.
>
> If you are using collocation and reclaimation is done, will ADSM -only-
> collocate a nodes backups on any one cart?  Or, will it just gather up a
> nodes backups that need to be "reclaimed" to a new cart and then do the
> same
> for another node until the cart is full?
>
> Dave Sanders
> Sr. Technical Consultant
> MassMutual / The Blue Chip Company
> 1295 State St, E060, Springfield, MA 01111
> 413-744-5095