Richard Sims wrote:
> On Mar 13, 2006, at 5:55 PM, Remco Post wrote:
>
>> So now for the question at hand, how do aggregation and the maxsize
>> parameter interact? Both during B/A and migration/reclamation?
>
> Remco -
>
> There's no mystery in this - it's all laid out in the IBM
> documentation, as previously indicated. During backup, client data is
> formed into a transaction according to the limits imposed by the TXN*
> parameters, and if the determined size fits in the primary landing
> area, it goes there, else further down in the stgpool hierarchy.
> Migration can happen if the current size of an Aggregate fits in the
> next lower stgpool.
>
Thanks,
and of course, since the landing area is determined before the actual
start of the data-transfer, in filesystem sizes are used to determine
the expected size of the transaction during b/a activity. The actual
size of the aggregate is used during migration/reclamation/whatever
since at that time that value is known.
> Your desire to service restorals without tape argues for an
> investment in some kind of disk array, with a Migdelay value such
> that older data migrates to tape.
>
Well, actually, I've been thinking about that. I would probably set a
migdelay, but make it huge (years?) for the smaller file pool and maybe
set it to a few days (or a week or so) for (disk-/file-)pools that hold
the larger files.
Anyway, I think I can now present a clear picture of both cost and
benefits to management.
> a weary Richard Sims
Thanks for your clarification, your help and a good nights rest did
wonders ;-)
--
Met vriendelijke groeten,
Remco Post
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